Check more preconditions in Debug mode

low bits of lcg have low periods

Bench.cpp

@@ -358,7 +358,14 @@ void benchWorstCaseForRadixRangeRead() {
   // }
 }
 
+void benchCreateAndDestroy() {
+  ankerl::nanobench::Bench bench;
+
+  bench.run("create and destroy", [&]() { ConflictSet cs{0}; });
+}
+
 int main(void) {
   benchConflictSet();
   benchWorstCaseForRadixRangeRead();
+  benchCreateAndDestroy();
 }

CMakeLists.txt

@@ -1,7 +1,7 @@
 cmake_minimum_required(VERSION 3.18)
 project(
   conflict-set
-  VERSION 0.0.7
+  VERSION 0.0.13
   DESCRIPTION
     "A data structure for optimistic concurrency control on ranges of bitwise-lexicographically-ordered keys."
   HOMEPAGE_URL "https://git.weaselab.dev/weaselab/conflict-set"
@@ -19,12 +19,6 @@ include(CheckCXXSourceCompiles)
 
 set(DEFAULT_BUILD_TYPE "Release")
 
-if(EMSCRIPTEN OR CMAKE_SYSTEM_NAME STREQUAL WASI)
-  set(WASM ON)
-else()
-  set(WASM OFF)
-endif()
-
 if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
   message(
     STATUS
@@ -39,6 +33,10 @@ endif()
 
 add_compile_options(-fdata-sections -ffunction-sections -Wswitch-enum
                     -Werror=switch-enum -fPIC)
+if(NOT APPLE)
+  # This causes some versions of clang to crash on macos
+  add_compile_options(-g -fno-omit-frame-pointer)
+endif()
 
 set(full_relro_flags "-pie;LINKER:-z,relro,-z,now,-z,noexecstack")
 cmake_push_check_state()
@@ -60,6 +58,8 @@ cmake_pop_check_state()
 option(USE_SIMD_FALLBACK
        "Use fallback implementations of functions that use SIMD" OFF)
 
+option(DISABLE_TSAN "Disable TSAN" OFF)
+
 # This is encouraged according to
 # https://valgrind.org/docs/manual/manual-core-adv.html#manual-core-adv.clientreq
 include_directories(SYSTEM ${CMAKE_CURRENT_SOURCE_DIR}/third_party/valgrind)
@@ -79,15 +79,6 @@ if(EMSCRIPTEN)
 endif()
 
 if(NOT USE_SIMD_FALLBACK)
-  cmake_push_check_state()
-  list(APPEND CMAKE_REQUIRED_FLAGS -msimd128)
-  check_include_file_cxx("wasm_simd128.h" HAS_WASM_SIMD)
-  if(HAS_WASM_SIMD)
-    add_compile_options(-msimd128)
-    add_compile_definitions(HAS_WASM_SIMD)
-  endif()
-  cmake_pop_check_state()
-
   cmake_push_check_state()
   list(APPEND CMAKE_REQUIRED_FLAGS -mavx)
   check_include_file_cxx("immintrin.h" HAS_AVX)
@@ -160,47 +151,40 @@ if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR AND BUILD_TESTING)
 
   file(GLOB CORPUS_TESTS ${CMAKE_CURRENT_SOURCE_DIR}/corpus/*)
 
-  # extra testing that relies on shared libraries, which aren't available with
-  # wasm
-  if(NOT WASM)
-    # Shared library version of FoundationDB's skip list implementation
-    add_library(skip_list SHARED SkipList.cpp)
-    target_compile_options(skip_list PRIVATE -fno-exceptions
-                                             -fvisibility=hidden)
-    target_include_directories(skip_list
-                               PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include)
-    set_target_properties(
-      skip_list PROPERTIES LIBRARY_OUTPUT_DIRECTORY
-                           "${CMAKE_CURRENT_BINARY_DIR}/skip_list")
-    set_target_properties(skip_list PROPERTIES OUTPUT_NAME ${PROJECT_NAME})
-    set_target_properties(
-      skip_list PROPERTIES VERSION ${PROJECT_VERSION} SOVERSION
-                                                      ${PROJECT_VERSION_MAJOR})
+  # Shared library version of FoundationDB's skip list implementation
+  add_library(skip_list SHARED SkipList.cpp)
+  target_compile_options(skip_list PRIVATE -fno-exceptions -fvisibility=hidden)
+  target_include_directories(skip_list
+                             PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include)
+  set_target_properties(
+    skip_list PROPERTIES LIBRARY_OUTPUT_DIRECTORY
+                         "${CMAKE_CURRENT_BINARY_DIR}/skip_list")
+  set_target_properties(skip_list PROPERTIES OUTPUT_NAME ${PROJECT_NAME})
+  set_target_properties(skip_list PROPERTIES VERSION ${PROJECT_VERSION}
+                                             SOVERSION ${PROJECT_VERSION_MAJOR})
 
-    # Shared library version of a std::unordered_map-based conflict set (point
-    # queries only)
-    add_library(hash_table SHARED HashTable.cpp)
-    target_compile_options(hash_table PRIVATE -fno-exceptions
-                                              -fvisibility=hidden)
-    target_include_directories(hash_table
-                               PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include)
-    set_target_properties(
-      hash_table PROPERTIES LIBRARY_OUTPUT_DIRECTORY
-                            "${CMAKE_CURRENT_BINARY_DIR}/hash_table")
-    set_target_properties(hash_table PROPERTIES OUTPUT_NAME ${PROJECT_NAME})
-    set_target_properties(
-      hash_table PROPERTIES VERSION ${PROJECT_VERSION} SOVERSION
-                                                       ${PROJECT_VERSION_MAJOR})
+  # Shared library version of a std::unordered_map-based conflict set (point
+  # queries only)
+  add_library(hash_table SHARED HashTable.cpp)
+  target_compile_options(hash_table PRIVATE -fno-exceptions -fvisibility=hidden)
+  target_include_directories(hash_table
+                             PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include)
+  set_target_properties(
+    hash_table PROPERTIES LIBRARY_OUTPUT_DIRECTORY
+                          "${CMAKE_CURRENT_BINARY_DIR}/hash_table")
+  set_target_properties(hash_table PROPERTIES OUTPUT_NAME ${PROJECT_NAME})
+  set_target_properties(
+    hash_table PROPERTIES VERSION ${PROJECT_VERSION} SOVERSION
+                                                     ${PROJECT_VERSION_MAJOR})
 
-    add_executable(driver_skip_list TestDriver.cpp)
-    target_compile_options(driver_skip_list PRIVATE ${TEST_FLAGS})
-    target_link_libraries(driver_skip_list PRIVATE skip_list)
+  add_executable(driver_skip_list TestDriver.cpp)
+  target_compile_options(driver_skip_list PRIVATE ${TEST_FLAGS})
+  target_link_libraries(driver_skip_list PRIVATE skip_list)
 
-    foreach(TEST ${CORPUS_TESTS})
-      get_filename_component(hash ${TEST} NAME)
-      add_test(NAME skip_list_${hash} COMMAND driver_skip_list ${TEST})
-    endforeach()
-  endif()
+  foreach(TEST ${CORPUS_TESTS})
+    get_filename_component(hash ${TEST} NAME)
+    add_test(NAME skip_list_${hash} COMMAND driver_skip_list ${TEST})
+  endforeach()
 
   # ad hoc testing
   add_executable(conflict_set_main ConflictSet.cpp)
@@ -245,7 +229,7 @@ if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR AND BUILD_TESTING)
   endforeach()
 
   # tsan tests
-  if(NOT CMAKE_CROSSCOMPILING AND NOT CMAKE_BUILD_TYPE STREQUAL Debug)
+  if(NOT CMAKE_CROSSCOMPILING AND NOT DISABLE_TSAN)
     add_executable(tsan_driver ConflictSet.cpp FuzzTestDriver.cpp)
     target_compile_options(tsan_driver PRIVATE ${TEST_FLAGS} -fsanitize=thread)
     target_link_options(tsan_driver PRIVATE -fsanitize=thread)
@@ -292,9 +276,15 @@ if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR AND BUILD_TESTING)
 
   find_program(VALGRIND_EXE valgrind)
   if(VALGRIND_EXE AND NOT CMAKE_CROSSCOMPILING)
-    add_test(NAME conflict_set_blackbox_valgrind
-             COMMAND ${VALGRIND_EXE} --error-exitcode=99 --
-                     $<TARGET_FILE:driver> ${CORPUS_TESTS})
+    list(LENGTH CORPUS_TESTS len)
+    math(EXPR last "${len} - 1")
+    set(partition_size 100)
+    foreach(i RANGE 0 ${last} ${partition_size})
+      list(SUBLIST CORPUS_TESTS ${i} ${partition_size} partition)
+      add_test(NAME conflict_set_blackbox_valgrind_${i}
+               COMMAND ${VALGRIND_EXE} --error-exitcode=99 --
+                       $<TARGET_FILE:driver> ${partition})
+    endforeach()
   endif()
 
   # api smoke tests
@@ -318,7 +308,7 @@ if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR AND BUILD_TESTING)
   add_test(NAME conflict_set_cxx_api_test COMMAND conflict_set_cxx_api_test)
 
   # symbol visibility tests
-  if(NOT WASM AND NOT CMAKE_BUILD_TYPE STREQUAL Debug)
+  if(NOT CMAKE_BUILD_TYPE STREQUAL Debug)
     if(APPLE)
       set(symbol_exports ${CMAKE_CURRENT_SOURCE_DIR}/apple-symbol-exports.txt)
       set(symbol_imports ${CMAKE_CURRENT_SOURCE_DIR}/apple-symbol-imports.txt)
@@ -351,6 +341,16 @@ if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR AND BUILD_TESTING)
   add_executable(real_data_bench RealDataBench.cpp)
   target_link_libraries(real_data_bench PRIVATE ${PROJECT_NAME})
   set_target_properties(real_data_bench PROPERTIES SKIP_BUILD_RPATH ON)
+
+  # fuzzer-based perf
+  add_executable(driver_perf TestDriver.cpp)
+  target_compile_definitions(driver_perf PRIVATE PERF_TEST=1)
+  target_link_libraries(driver_perf PRIVATE ${PROJECT_NAME})
+
+  # server bench
+  add_executable(server_bench ServerBench.cpp)
+  target_link_libraries(server_bench PRIVATE ${PROJECT_NAME})
+  set_target_properties(server_bench PROPERTIES SKIP_BUILD_RPATH ON)
 endif()
 
 # packaging

HashTable.cpp

@@ -98,6 +98,13 @@ void ConflictSet::setOldestVersion(int64_t oldestVersion) {
 
 int64_t ConflictSet::getBytes() const { return -1; }
 
+void ConflictSet::getMetricsV1(MetricsV1 **metrics, int *count) const {
+  *metrics = nullptr;
+  *count = 0;
+}
+
+double ConflictSet::MetricsV1::getValue() const { return 0; }
+
 ConflictSet::ConflictSet(int64_t oldestVersion)
     : impl(new(safe_malloc(sizeof(Impl))) Impl{oldestVersion}) {}
 

Internal.h

@@ -20,7 +20,6 @@ using namespace weaselab;
 #include <thread>
 #include <unordered_set>
 #include <utility>
-#include <vector>
 
 #include <callgrind.h>
 
@@ -273,6 +272,16 @@ template <class T> struct Vector {
     size_ += slice.size();
   }
 
+  // Caller must write to the returned slice
+  std::span<T> unsafePrepareAppend(int appendSize) {
+    if (size_ + appendSize > capacity) {
+      grow(std::max<int>(size_ + appendSize, capacity * 2));
+    }
+    auto result = std::span<T>(t + size_, appendSize);
+    size_ += appendSize;
+    return result;
+  }
+
   void push_back(const T &t) { append(std::span<const T>(&t, 1)); }
 
   T *begin() { return t; }
@@ -578,12 +587,16 @@ inline const char *resultToStr(ConflictSet::Result r) {
 
 namespace {
 
-template <class ConflictSetImpl> struct TestDriver {
-  Arbitrary arbitrary;
-  explicit TestDriver(const uint8_t *data, size_t size)
-      : arbitrary({data, size}) {}
+template <class ConflictSetImpl, bool kEnableAssertions = true>
+struct TestDriver {
+  Arbitrary *arbitrary;
+  explicit TestDriver(Arbitrary &a) : arbitrary(&a) {
+#if DEBUG_VERBOSE && !defined(NDEBUG)
+    fprintf(stderr, "%p Initial version: {%" PRId64 "}\n", this, writeVersion);
+#endif
+  }
 
-  int64_t oldestVersion = arbitrary.next();
+  int64_t oldestVersion = arbitrary->next();
   int64_t writeVersion = oldestVersion;
   ConflictSetImpl cs{oldestVersion};
   ReferenceImpl refImpl{oldestVersion};
@@ -592,33 +605,34 @@ template <class ConflictSetImpl> struct TestDriver {
 
   bool ok = true;
 
-  const int prefixLen = arbitrary.bounded(512);
-  const int prefixByte = arbitrary.randT<uint8_t>();
+  const int prefixLen = arbitrary->bounded(512);
+  const int prefixByte = arbitrary->randT<uint8_t>();
 
   // Call until it returns true, for "done". Check internal invariants etc
   // between calls to next.
   bool next() {
     assert(cs.getBytes() >= 0);
-    if (!arbitrary.hasEntropy()) {
+    if (!arbitrary->hasEntropy()) {
       return true;
     }
     Arena arena;
     {
-      int numPointWrites = arbitrary.bounded(100);
-      int numRangeWrites = arbitrary.bounded(100);
-      int64_t v = (writeVersion += arbitrary.bounded(10) ? arbitrary.bounded(10)
-                                                         : arbitrary.next());
+      int numPointWrites = arbitrary->bounded(100);
+      int numRangeWrites = arbitrary->bounded(100);
+      int64_t v =
+          (writeVersion +=
+           arbitrary->bounded(10) ? arbitrary->bounded(10) : arbitrary->next());
       auto *writes =
           new (arena) ConflictSet::WriteRange[numPointWrites + numRangeWrites];
       auto keys = set<std::string_view>(arena);
       while (int(keys.size()) < numPointWrites + numRangeWrites * 2) {
-        if (!arbitrary.hasEntropy()) {
+        if (!arbitrary->hasEntropy()) {
           return true;
         }
-        int keyLen = prefixLen + arbitrary.bounded(kMaxKeySuffixLen);
+        int keyLen = prefixLen + arbitrary->bounded(kMaxKeySuffixLen);
         auto *begin = new (arena) uint8_t[keyLen];
         memset(begin, prefixByte, prefixLen);
-        arbitrary.randomBytes(begin + prefixLen, keyLen - prefixLen);
+        arbitrary->randomBytes(begin + prefixLen, keyLen - prefixLen);
         keys.insert(std::string_view((const char *)begin, keyLen));
       }
 
@@ -628,7 +642,7 @@ template <class ConflictSetImpl> struct TestDriver {
                rangesRemaining = numRangeWrites;
            pointsRemaining > 0 || rangesRemaining > 0; ++i) {
         bool pointRead = pointsRemaining > 0 && rangesRemaining > 0
-                             ? bool(arbitrary.bounded(2))
+                             ? bool(arbitrary->bounded(2))
                              : pointsRemaining > 0;
         if (pointRead) {
           assert(pointsRemaining > 0);
@@ -647,54 +661,123 @@ template <class ConflictSetImpl> struct TestDriver {
           ++iter;
           --rangesRemaining;
         }
-#if DEBUG_VERBOSE && !defined(NDEBUG)
-        if (writes[i].end.len == 0) {
-          fprintf(stderr, "Write: {%s}\n", printable(writes[i].begin).c_str());
-        } else {
-          fprintf(stderr, "Write: [%s, %s)\n",
-                  printable(writes[i].begin).c_str(),
-                  printable(writes[i].end).c_str());
-        }
-#endif
       }
       assert(iter == keys.end());
       assert(i == numPointWrites + numRangeWrites);
 
+      // Test non-canonical writes
+      if (numPointWrites > 0) {
+        int overlaps = arbitrary->bounded(numPointWrites);
+        for (int i = 0; i < numPointWrites + numRangeWrites && overlaps > 0;
+             ++i) {
+          if (writes[i].end.len == 0) {
+            int keyLen = prefixLen + arbitrary->bounded(kMaxKeySuffixLen);
+            auto *begin = new (arena) uint8_t[keyLen];
+            memset(begin, prefixByte, prefixLen);
+            arbitrary->randomBytes(begin + prefixLen, keyLen - prefixLen);
+            writes[i].end.len = keyLen;
+            writes[i].end.p = begin;
+            auto c =
+                std::span<const uint8_t>(writes[i].begin.p,
+                                         writes[i].begin.len) <=>
+                std::span<const uint8_t>(writes[i].end.p, writes[i].end.len);
+            if (c > 0) {
+              using std::swap;
+              swap(writes[i].begin, writes[i].end);
+            } else if (c == 0) {
+              // It's a point write after all, I guess
+              writes[i].end.len = 0;
+            }
+            --overlaps;
+          }
+        }
+      }
+      if (arbitrary->bounded(2)) {
+        // Shuffle writes
+        for (int i = numPointWrites + numRangeWrites - 1; i > 0; --i) {
+          int j = arbitrary->bounded(i + 1);
+          if (i != j) {
+            using std::swap;
+            swap(writes[i], writes[j]);
+          }
+        }
+      }
+
+      oldestVersion +=
+          arbitrary->bounded(10) ? arbitrary->bounded(10) : arbitrary->next();
+      oldestVersion = std::min(oldestVersion, writeVersion);
+
+#ifdef THREAD_TEST
+      std::latch ready{1};
+      std::thread thread2{[&]() {
+        ready.count_down();
+        ConflictSet::MetricsV1 *m;
+        int count;
+        cs.getMetricsV1(&m, &count);
+        for (int i = 0; i < count; ++i) {
+          m[i].getValue();
+        }
+      }};
+      ready.wait();
+#endif
+
 #if DEBUG_VERBOSE && !defined(NDEBUG)
-      fprintf(stderr, "Write @ %" PRId64 "\n", v);
+      for (int i = 0; i < numPointWrites + numRangeWrites; ++i) {
+        if (writes[i].end.len == 0) {
+          fprintf(stderr, "%p Write: {%s}\n", this,
+                  printable(writes[i].begin).c_str());
+        } else {
+          fprintf(stderr, "%p Write: [%s, %s)\n", this,
+                  printable(writes[i].begin).c_str(),
+                  printable(writes[i].end).c_str());
+        }
+      }
+      fprintf(stderr, "%p Write @ %" PRId64 "\n", this, v);
 #endif
 
       CALLGRIND_START_INSTRUMENTATION;
       cs.addWrites(writes, numPointWrites + numRangeWrites, v);
       CALLGRIND_STOP_INSTRUMENTATION;
 
-      refImpl.addWrites(writes, numPointWrites + numRangeWrites, v);
+      if constexpr (kEnableAssertions) {
+        refImpl.addWrites(writes, numPointWrites + numRangeWrites, v);
+      }
 
-      oldestVersion +=
-          arbitrary.bounded(10) ? arbitrary.bounded(10) : arbitrary.next();
-      oldestVersion = std::min(oldestVersion, writeVersion);
+#if DEBUG_VERBOSE && !defined(NDEBUG)
+      fprintf(stderr, "%p Set oldest version: %" PRId64 "\n", this,
+              oldestVersion);
+#endif
+      CALLGRIND_START_INSTRUMENTATION;
       cs.setOldestVersion(oldestVersion);
-      refImpl.setOldestVersion(oldestVersion);
+      CALLGRIND_STOP_INSTRUMENTATION;
+
+      if constexpr (kEnableAssertions) {
+        refImpl.setOldestVersion(oldestVersion);
+      }
+
+#ifdef THREAD_TEST
+      thread2.join();
+#endif
     }
     {
-      int numPointReads = arbitrary.bounded(100);
-      int numRangeReads = arbitrary.bounded(100);
+      int numPointReads = arbitrary->bounded(100);
+      int numRangeReads = arbitrary->bounded(100);
 
-      int64_t v = std::max<int64_t>(writeVersion - (arbitrary.bounded(10)
-                                                        ? arbitrary.bounded(10)
-                                                        : arbitrary.next()),
+      int64_t v = std::max<int64_t>(writeVersion - (arbitrary->bounded(10)
+                                                        ? arbitrary->bounded(10)
+                                                        : arbitrary->next()),
                                     0);
       auto *reads =
           new (arena) ConflictSet::ReadRange[numPointReads + numRangeReads];
       auto keys = set<std::string_view>(arena);
       while (int(keys.size()) < numPointReads + numRangeReads * 2) {
-        if (!arbitrary.hasEntropy()) {
+        if (!arbitrary->hasEntropy()) {
           return true;
         }
-        int keyLen = prefixLen + arbitrary.bounded(kMaxKeySuffixLen);
+        int keyLen = prefixLen + arbitrary->bounded(kMaxKeySuffixLen);
         auto *begin = new (arena) uint8_t[keyLen];
         memset(begin, prefixByte, prefixLen);
-        arbitrary.randomBytes(begin + prefixLen, keyLen - prefixLen);
+        arbitrary->randomBytes(begin + prefixLen, keyLen - prefixLen);
         keys.insert(std::string_view((const char *)begin, keyLen));
       }
 
@@ -703,7 +786,7 @@ template <class ConflictSetImpl> struct TestDriver {
       for (int pointsRemaining = numPointReads, rangesRemaining = numRangeReads;
            pointsRemaining > 0 || rangesRemaining > 0; ++i) {
         bool pointRead = pointsRemaining > 0 && rangesRemaining > 0
-                             ? bool(arbitrary.bounded(2))
+                             ? bool(arbitrary->bounded(2))
                              : pointsRemaining > 0;
         if (pointRead) {
           assert(pointsRemaining > 0);
@@ -725,10 +808,10 @@ template <class ConflictSetImpl> struct TestDriver {
         reads[i].readVersion = v;
 #if DEBUG_VERBOSE && !defined(NDEBUG)
         if (reads[i].end.len == 0) {
-          fprintf(stderr, "Read: {%s} @ %" PRId64 "\n",
+          fprintf(stderr, "%p Read: {%s} @ %" PRId64 "\n", this,
                   printable(reads[i].begin).c_str(), reads[i].readVersion);
         } else {
-          fprintf(stderr, "Read: [%s, %s) @ %" PRId64 "\n",
+          fprintf(stderr, "%p Read: [%s, %s) @ %" PRId64 "\n", this,
                   printable(reads[i].begin).c_str(),
                   printable(reads[i].end).c_str(), reads[i].readVersion);
         }
@@ -747,7 +830,15 @@ template <class ConflictSetImpl> struct TestDriver {
       std::latch ready{1};
       std::thread thread2{[&]() {
         ready.count_down();
+        // Call all const methods
         cs.check(reads, results3, numPointReads + numRangeReads);
+        cs.getBytes();
+        ConflictSet::MetricsV1 *m;
+        int count;
+        cs.getMetricsV1(&m, &count);
+        for (int i = 0; i < count; ++i) {
+          m[i].getValue();
+        }
       }};
       ready.wait();
 #endif
@@ -756,26 +847,40 @@ template <class ConflictSetImpl> struct TestDriver {
       cs.check(reads, results1, numPointReads + numRangeReads);
       CALLGRIND_STOP_INSTRUMENTATION;
 
-      refImpl.check(reads, results2, numPointReads + numRangeReads);
+      if constexpr (kEnableAssertions) {
+        // Call remaining const methods
+        cs.getBytes();
+        ConflictSet::MetricsV1 *m;
+        int count;
+        cs.getMetricsV1(&m, &count);
+        for (int i = 0; i < count; ++i) {
+          m[i].getValue();
+        }
 
-      auto compareResults = [reads](ConflictSet::Result *results1,
-                                    ConflictSet::Result *results2, int count) {
+        refImpl.check(reads, results2, numPointReads + numRangeReads);
+      }
+
+      auto compareResults = [reads, this](ConflictSet::Result *results1,
+                                          ConflictSet::Result *results2,
+                                          int count) {
         for (int i = 0; i < count; ++i) {
           if (results1[i] != results2[i]) {
             if (reads[i].end.len == 0) {
-              fprintf(stderr,
-                      "Expected %s, got %s for read of {%s} at version %" PRId64
-                      "\n",
-                      resultToStr(results2[i]), resultToStr(results1[i]),
-                      printable(reads[i].begin).c_str(), reads[i].readVersion);
-            } else {
               fprintf(
                   stderr,
-                  "Expected %s, got %s for read of [%s, %s) at version %" PRId64
+                  "%p Expected %s, got %s for read of {%s} at version %" PRId64
                   "\n",
-                  resultToStr(results2[i]), resultToStr(results1[i]),
-                  printable(reads[i].begin).c_str(),
-                  printable(reads[i].end).c_str(), reads[i].readVersion);
+                  (void *)this, resultToStr(results2[i]),
+                  resultToStr(results1[i]), printable(reads[i].begin).c_str(),
+                  reads[i].readVersion);
+            } else {
+              fprintf(stderr,
+                      "%p Expected %s, got %s for read of [%s, %s) at version "
+                      "%" PRId64 "\n",
+                      (void *)this, resultToStr(results2[i]),
+                      resultToStr(results1[i]),
+                      printable(reads[i].begin).c_str(),
+                      printable(reads[i].end).c_str(), reads[i].readVersion);
             }
             return false;
           }
@@ -783,9 +888,12 @@ template <class ConflictSetImpl> struct TestDriver {
         return true;
       };
 
-      if (!compareResults(results1, results2, numPointReads + numRangeReads)) {
-        ok = false;
-        return true;
+      if constexpr (kEnableAssertions) {
+        if (!compareResults(results1, results2,
+                            numPointReads + numRangeReads)) {
+          ok = false;
+          return true;
+        }
       }
 
 #ifdef THREAD_TEST

Jenkinsfile

@@ -48,6 +48,28 @@ pipeline {
                 recordIssues(tools: [clang()])
             }
         }
+        stage('64 bit versions') {
+            agent {
+                dockerfile {
+                    args '-v /home/jenkins/ccache:/ccache'
+                    reuseNode true
+                }
+            }
+            steps {
+                CleanBuildAndTest("-DCMAKE_CXX_FLAGS=-DUSE_64_BIT=1")
+            }
+        }
+        stage('Debug') {
+            agent {
+                dockerfile {
+                    args '-v /home/jenkins/ccache:/ccache'
+                    reuseNode true
+                }
+            }
+            steps {
+                CleanBuildAndTest("-DCMAKE_BUILD_TYPE=Debug")
+            }
+        }
         stage('SIMD fallback') {
             agent {
                 dockerfile {
@@ -59,17 +81,6 @@ pipeline {
                 CleanBuildAndTest("-DUSE_SIMD_FALLBACK=ON")
             }
         }
-        stage('32-bit versions') {
-            agent {
-                dockerfile {
-                    args '-v /home/jenkins/ccache:/ccache'
-                    reuseNode true
-                }
-            }
-            steps {
-                CleanBuildAndTest("-DUSE_32_BIT_VERSIONS=ON")
-            }
-        }
         stage('Release [gcc]') {
             agent {
                 dockerfile {
@@ -117,15 +128,18 @@ pipeline {
                 }
             }
             steps {
-                CleanBuildAndTest("-DCMAKE_C_COMPILER=gcc -DCMAKE_CXX_COMPILER=g++ -DCMAKE_C_FLAGS=--coverage -DCMAKE_CXX_FLAGS=--coverage -DCMAKE_BUILD_TYPE=Debug")
-                sh '''
-                gcovr -f ConflictSet.cpp --cobertura > build/coverage.xml
-                '''
+                script {
+                    filter_args = "-f ConflictSet.cpp -f LongestCommonPrefix.h"
+                }
+                CleanBuildAndTest("-DCMAKE_C_COMPILER=gcc -DCMAKE_CXX_COMPILER=g++ -DCMAKE_C_FLAGS=--coverage -DCMAKE_CXX_FLAGS=--coverage -DCMAKE_BUILD_TYPE=Debug -DDISABLE_TSAN=ON")
+                sh """
+                gcovr ${filter_args} --cobertura > build/coverage.xml
+                """
                 recordCoverage qualityGates: [[criticality: 'NOTE', metric: 'MODULE']], tools: [[parser: 'COBERTURA', pattern: 'build/coverage.xml']]
-                sh '''
-                # Suppress again, because we haven't dealt with function multi-versioning for x86 yet
-                # gcovr -f ConflictSet.cpp --fail-under-line 100 > /dev/null
-                '''
+                sh """
+                gcovr ${filter_args}
+                gcovr ${filter_args} --fail-under-line 100 > /dev/null
+                """
             }
         }
     }

LongestCommonPrefix.h

@@ -0,0 +1,185 @@
+#pragma once
+
+#include <assert.h>
+#include <bit>
+#include <stdint.h>
+#include <string.h>
+
+#ifdef HAS_AVX
+#include <immintrin.h>
+#elif HAS_ARM_NEON
+#include <arm_neon.h>
+#endif
+
+#ifndef __SANITIZE_THREAD__
+#if defined(__has_feature)
+#if __has_feature(thread_sanitizer)
+#define __SANITIZE_THREAD__
+#endif
+#endif
+#endif
+
+#if defined(HAS_AVX) || defined(HAS_ARM_NEON)
+constexpr int kStride = 64;
+#else
+constexpr int kStride = 16;
+#endif
+
+constexpr int kUnrollFactor = 4;
+
+inline bool compareStride(const uint8_t *ap, const uint8_t *bp) {
+#if defined(HAS_ARM_NEON)
+  static_assert(kStride == 64);
+  uint8x16_t x[4]; // GCOVR_EXCL_LINE
+  for (int i = 0; i < 4; ++i) {
+    x[i] = vceqq_u8(vld1q_u8(ap + i * 16), vld1q_u8(bp + i * 16));
+  }
+  auto results = vreinterpretq_u16_u8(
+      vandq_u8(vandq_u8(x[0], x[1]), vandq_u8(x[2], x[3])));
+  bool eq = vget_lane_u64(vreinterpret_u64_u8(vshrn_n_u16(results, 4)), 0) ==
+            uint64_t(-1);
+#elif defined(HAS_AVX)
+  static_assert(kStride == 64);
+  __m128i x[4]; // GCOVR_EXCL_LINE
+  for (int i = 0; i < 4; ++i) {
+    x[i] = _mm_cmpeq_epi8(_mm_loadu_si128((__m128i *)(ap + i * 16)),
+                          _mm_loadu_si128((__m128i *)(bp + i * 16)));
+  }
+  auto eq =
+      _mm_movemask_epi8(_mm_and_si128(_mm_and_si128(x[0], x[1]),
+                                      _mm_and_si128(x[2], x[3]))) == 0xffff;
+#else
+  // Hope it gets vectorized
+  auto eq = memcmp(ap, bp, kStride) == 0;
+#endif
+  return eq;
+}
+
+// Precondition: ap[:kStride] != bp[:kStride]
+inline int firstNeqStride(const uint8_t *ap, const uint8_t *bp) {
+#if defined(HAS_AVX)
+  static_assert(kStride == 64);
+  uint64_t c[kStride / 16]; // GCOVR_EXCL_LINE
+  for (int i = 0; i < kStride; i += 16) {
+    const auto a = _mm_loadu_si128((__m128i *)(ap + i));
+    const auto b = _mm_loadu_si128((__m128i *)(bp + i));
+    const auto compared = _mm_cmpeq_epi8(a, b);
+    c[i / 16] = _mm_movemask_epi8(compared) & 0xffff;
+  }
+  return std::countr_zero(~(c[0] | c[1] << 16 | c[2] << 32 | c[3] << 48));
+#elif defined(HAS_ARM_NEON)
+  static_assert(kStride == 64);
+  for (int i = 0; i < kStride; i += 16) {
+    // 0xff for each match
+    uint16x8_t results =
+        vreinterpretq_u16_u8(vceqq_u8(vld1q_u8(ap + i), vld1q_u8(bp + i)));
+    // 0xf for each mismatch
+    uint64_t bitfield =
+        ~vget_lane_u64(vreinterpret_u64_u8(vshrn_n_u16(results, 4)), 0);
+    if (bitfield) {
+      return i + (std::countr_zero(bitfield) >> 2);
+    }
+  }
+  __builtin_unreachable(); // GCOVR_EXCL_LINE
+#else
+  int i = 0;
+  for (; i < kStride - 1; ++i) {
+    if (*ap++ != *bp++) {
+      break;
+    }
+  }
+  return i;
+#endif
+}
+
+// This gets covered in local development
+// GCOVR_EXCL_START
+#if defined(HAS_AVX) && !defined(__SANITIZE_THREAD__)
+__attribute__((target("avx512f,avx512bw"))) inline int
+longestCommonPrefix(const uint8_t *ap, const uint8_t *bp, int cl) {
+  int i = 0;
+  int end = cl & ~63;
+  while (i < end) {
+    const uint64_t eq =
+        _mm512_cmpeq_epi8_mask(_mm512_loadu_epi8(ap), _mm512_loadu_epi8(bp));
+    if (eq != uint64_t(-1)) {
+      return i + std::countr_one(eq);
+    }
+    i += 64;
+    ap += 64;
+    bp += 64;
+  }
+  if (i < cl) {
+    const uint64_t mask = (uint64_t(1) << (cl - i)) - 1;
+    const uint64_t eq = _mm512_cmpeq_epi8_mask(
+        _mm512_maskz_loadu_epi8(mask, ap), _mm512_maskz_loadu_epi8(mask, bp));
+    return i + std::countr_one(eq & mask);
+  }
+  assert(i == cl);
+  return i;
+}
+__attribute__((target("default")))
+#endif
+// GCOVR_EXCL_STOP
+
+inline int
+longestCommonPrefix(const uint8_t *ap, const uint8_t *bp, int cl) {
+  if (!(cl >= 0)) {
+    __builtin_unreachable(); // GCOVR_EXCL_LINE
+  }
+
+  int i = 0;
+  int end;
+
+  // kStride * kUnrollCount at a time
+  end = cl & ~(kStride * kUnrollFactor - 1);
+  while (i < end) {
+    for (int j = 0; j < kUnrollFactor; ++j) {
+      if (!compareStride(ap, bp)) {
+        return i + firstNeqStride(ap, bp);
+      }
+      i += kStride;
+      ap += kStride;
+      bp += kStride;
+    }
+  }
+
+  // kStride at a time
+  end = cl & ~(kStride - 1);
+  while (i < end) {
+    if (!compareStride(ap, bp)) {
+      return i + firstNeqStride(ap, bp);
+    }
+    i += kStride;
+    ap += kStride;
+    bp += kStride;
+  }
+
+  // word at a time
+  end = cl & ~(sizeof(uint64_t) - 1);
+  while (i < end) {
+    uint64_t a; // GCOVR_EXCL_LINE
+    uint64_t b; // GCOVR_EXCL_LINE
+    memcpy(&a, ap, 8);
+    memcpy(&b, bp, 8);
+    const auto mismatched = a ^ b;
+    if (mismatched) {
+      return i + std::countr_zero(mismatched) / 8;
+    }
+    i += 8;
+    ap += 8;
+    bp += 8;
+  }
+
+  // byte at a time
+  while (i < cl) {
+    if (*ap != *bp) {
+      break;
+    }
+    ++ap;
+    ++bp;
+    ++i;
+  }
+
+  return i;
+}

README.md

@@ -1,86 +1,38 @@
 A data structure for optimistic concurrency control on ranges of bitwise-lexicographically-ordered keys.
 
-Intended to replace FoundationDB's skip list.
+Intended as an alternative to FoundationDB's skip list.
 
-Hardware for all benchmarks is a mac m1 2020.
+Hardware for all benchmarks is an AMD Ryzen 9 7900 with (2x32GB) 5600MT/s CL28-34-34-89 1.35V RAM
 
-# FoundationDB's benchmark
+# Microbenchmark
 
 ## Skip list
 
-```
-New conflict set: 1.957 sec
-                  0.639 Mtransactions/sec
-                  2.555 Mkeys/sec
-Detect only:      1.845 sec
-                  0.678 Mtransactions/sec
-                  2.710 Mkeys/sec
-Skiplist only:    1.263 sec
-                  0.990 Mtransactions/sec
-                  3.960 Mkeys/sec
-Performance counters:
-               Build: 0.0546
-                 Add: 0.0563
-              Detect: 1.84
-              D.Sort: 0.412
-           D.Combine: 0.0141
-         D.CheckRead: 0.671
-   D.CheckIntraBatch: 0.0068
-        D.MergeWrite: 0.592
-      D.RemoveBefore: 0.146
-```
+|               ns/op |                op/s |    err% |          ins/op |          cyc/op |    IPC |         bra/op |   miss% |     total | benchmark
+|--------------------:|--------------------:|--------:|----------------:|----------------:|-------:|---------------:|--------:|----------:|:----------
+|              172.03 |        5,812,791.77 |    0.4% |        3,130.62 |          879.00 |  3.562 |         509.23 |    0.0% |      0.01 | `point reads`
+|              167.44 |        5,972,130.71 |    0.2% |        3,065.14 |          862.27 |  3.555 |         494.30 |    0.0% |      0.01 | `prefix reads`
+|              238.77 |        4,188,130.84 |    0.9% |        3,589.93 |        1,259.30 |  2.851 |         637.12 |    0.0% |      0.01 | `range reads`
+|              424.01 |        2,358,426.70 |    0.2% |        5,620.05 |        2,242.35 |  2.506 |         854.80 |    1.7% |      0.01 | `point writes`
+|              418.45 |        2,389,780.56 |    0.4% |        5,525.07 |        2,211.05 |  2.499 |         831.71 |    1.7% |      0.01 | `prefix writes`
+|              254.87 |        3,923,568.88 |    2.6% |        3,187.01 |        1,366.50 |  2.332 |         529.11 |    2.7% |      0.02 | `range writes`
+|              675.96 |        1,479,374.50 |    3.3% |        7,735.41 |        3,468.60 |  2.230 |       1,386.02 |    1.8% |      0.01 | `monotonic increasing point writes`
+|          137,986.20 |            7,247.10 |    0.6% |      789,752.33 |      699,462.00 |  1.129 |     144,824.14 |    0.0% |      0.01 | `worst case for radix tree`
+|               21.63 |       46,231,564.03 |    1.0% |          448.00 |          107.14 |  4.181 |          84.00 |    0.0% |      0.01 | `create and destroy`
 
 ## Radix tree (this implementation)
 
-```
-New conflict set: 1.366 sec
-                  0.915 Mtransactions/sec
-                  3.660 Mkeys/sec
-Detect only:      1.248 sec
-                  1.002 Mtransactions/sec
-                  4.007 Mkeys/sec
-Skiplist only:    0.573 sec
-                  2.182 Mtransactions/sec
-                  8.730 Mkeys/sec
-Performance counters:
-               Build: 0.0594
-                 Add: 0.0572
-              Detect: 1.25
-              D.Sort: 0.418
-           D.Combine: 0.0149
-         D.CheckRead: 0.232
-   D.CheckIntraBatch: 0.0067
-        D.MergeWrite: 0.341
-      D.RemoveBefore: 0.232
-```
-
-# Our benchmark
-
-## Skip list
-
-|               ns/op |                op/s |    err% |     total | benchmark
-|--------------------:|--------------------:|--------:|----------:|:----------
-|              256.89 |        3,892,784.92 |    0.3% |      0.01 | `point reads`
-|              272.90 |        3,664,395.04 |    0.2% |      0.01 | `prefix reads`
-|              507.22 |        1,971,549.50 |    0.7% |      0.01 | `range reads`
-|              452.66 |        2,209,181.91 |    0.5% |      0.01 | `point writes`
-|              438.09 |        2,282,619.96 |    0.4% |      0.01 | `prefix writes`
-|              253.33 |        3,947,420.36 |    2.5% |      0.02 | `range writes`
-|              574.07 |        1,741,936.71 |    0.3% |      0.01 | `monotonic increasing point writes`
-|          151,562.50 |            6,597.94 |    1.5% |      0.01 | `worst case for radix tree`
-
-## Radix tree (this implementation)
-
-|               ns/op |                op/s |    err% |     total | benchmark
-|--------------------:|--------------------:|--------:|----------:|:----------
-|               19.83 |       50,420,955.28 |    0.1% |      0.01 | `point reads`
-|               55.95 |       17,872,542.40 |    0.5% |      0.01 | `prefix reads`
-|               88.28 |       11,327,709.50 |    0.4% |      0.01 | `range reads`
-|               29.15 |       34,309,531.64 |    0.5% |      0.01 | `point writes`
-|               42.36 |       23,607,424.27 |    1.1% |      0.01 | `prefix writes`
-|               50.00 |       20,000,000.00 |    0.0% |      0.01 | `range writes`
-|               93.52 |       10,692,413.79 |    3.3% |      0.01 | `monotonic increasing point writes`
-|        2,388,417.00 |              418.69 |    0.4% |      0.03 | `worst case for radix tree`
+|               ns/op |                op/s |    err% |          ins/op |          cyc/op |    IPC |         bra/op |   miss% |     total | benchmark
+|--------------------:|--------------------:|--------:|----------------:|----------------:|-------:|---------------:|--------:|----------:|:----------
+|               11.18 |       89,455,125.34 |    0.6% |          185.37 |           57.08 |  3.248 |          41.51 |    0.4% |      0.01 | `point reads`
+|               14.53 |       68,800,688.89 |    0.4% |          282.41 |           74.80 |  3.776 |          55.06 |    0.3% |      0.01 | `prefix reads`
+|               36.54 |       27,367,576.87 |    0.2% |          798.06 |          188.90 |  4.225 |         141.69 |    0.2% |      0.01 | `range reads`
+|               16.69 |       59,912,106.02 |    0.6% |          314.57 |           86.29 |  3.645 |          39.84 |    0.4% |      0.01 | `point writes`
+|               30.09 |       33,235,744.07 |    0.5% |          591.33 |          155.92 |  3.793 |          82.69 |    0.2% |      0.01 | `prefix writes`
+|               35.77 |       27,956,388.03 |    1.4% |          682.25 |          187.63 |  3.636 |          96.12 |    0.1% |      0.01 | `range writes`
+|               74.04 |       13,505,408.41 |    2.7% |        1,448.95 |          392.10 |  3.695 |         260.53 |    0.1% |      0.01 | `monotonic increasing point writes`
+|          330,984.50 |            3,021.29 |    1.9% |    3,994,153.50 |    1,667,309.00 |  2.396 |     806,019.50 |    0.0% |      0.01 | `worst case for radix tree`
+|               92.46 |       10,814,961.65 |    0.5% |        1,800.00 |          463.41 |  3.884 |         297.00 |    0.0% |      0.01 | `create and destroy`
 
 # "Real data" test
 
@@ -89,13 +41,13 @@ Point queries only, best of three runs. Gc ratio is the ratio of time spent doin
 ## skip list
 
 ```
-Check: 11.3385 seconds, 329.718 MB/s, Add: 5.35612 seconds, 131.072 MB/s, Gc ratio: 45.7173%
+Check: 4.47891 seconds, 364.05 MB/s, Add: 4.55599 seconds, 123.058 MB/s, Gc ratio: 37.1145%
 ```
 
 ## radix tree
 
 ```
-Check: 2.48583 seconds, 1503.93 MB/s, Add: 2.12768 seconds, 329.954 MB/s, Gc ratio: 41.7943%
+Check: 0.953012 seconds, 1710.94 MB/s, Add: 1.30025 seconds, 431.188 MB/s, Gc ratio: 43.9816%, Peak idle memory: 2.28375e+06
 ```
 
 ## hash table
@@ -103,5 +55,5 @@ Check: 2.48583 seconds, 1503.93 MB/s, Add: 2.12768 seconds, 329.954 MB/s, Gc rat
 (The hash table implementation doesn't work on range queries, and its purpose is to provide an idea of how fast point queries can be)
 
 ```
-Check: 1.83386 seconds, 2038.6 MB/s, Add: 0.601411 seconds, 1167.32 MB/s, Gc ratio: 48.9776%
+Check: 0.804094 seconds, 2027.81 MB/s, Add: 0.652952 seconds, 858.645 MB/s, Gc ratio: 35.3885%
 ```

RealDataBench.cpp

@@ -129,6 +129,16 @@ int main(int argc, const char **argv) {
     close(fd);
   }
 
+  ConflictSet::MetricsV1 *metrics;
+  int metricsCount;
+  cs.getMetricsV1(&metrics, &metricsCount);
+  for (int i = 0; i < metricsCount; ++i) {
+    printf("# HELP %s %s\n", metrics[i].name, metrics[i].help);
+    printf("# TYPE %s %s\n", metrics[i].name,
+           metrics[i].type == metrics[i].Counter ? "counter" : "gauge");
+    printf("%s %g\n", metrics[i].name, metrics[i].getValue());
+  }
+
   printf("Check: %g seconds, %g MB/s, Add: %g seconds, %g MB/s, Gc ratio: "
          "%g%%, Peak idle memory: %g\n",
          checkTime, checkBytes / checkTime * 1e-6, addTime,

ServerBench.cpp

@@ -0,0 +1,369 @@
+#include <atomic>
+#include <errno.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <string>
+#include <string_view>
+#include <sys/ioctl.h>
+#include <sys/resource.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/uio.h>
+#include <thread>
+#include <unistd.h>
+#include <utility>
+#include <vector>
+
+#include "ConflictSet.h"
+#include "third_party/nadeau.h"
+
+std::atomic<int64_t> transactions;
+
+constexpr int kBaseSearchDepth = 32;
+constexpr int kWindowSize = 10000000;
+
+std::string numToKey(int64_t num) {
+  std::string result;
+  result.resize(kBaseSearchDepth + sizeof(int64_t));
+  memset(result.data(), 0, kBaseSearchDepth);
+  int64_t be = __builtin_bswap64(num);
+  memcpy(result.data() + kBaseSearchDepth, &be, sizeof(int64_t));
+  return result;
+}
+
+void workload(weaselab::ConflictSet *cs) {
+  int64_t version = kWindowSize;
+  cs->addWrites(nullptr, 0, version);
+  for (;; transactions.fetch_add(1, std::memory_order_relaxed)) {
+    // Reads
+    {
+      auto beginK = numToKey(version - kWindowSize);
+      auto endK = numToKey(version - 1);
+      auto pointRv = version - kWindowSize + rand() % kWindowSize + 1;
+      auto pointK = numToKey(pointRv);
+      weaselab::ConflictSet::ReadRange reads[] = {
+          {
+              {(const uint8_t *)pointK.data(), int(pointK.size())},
+              {nullptr, 0},
+              pointRv,
+          },
+          {
+              {(const uint8_t *)beginK.data(), int(beginK.size())},
+              {(const uint8_t *)endK.data(), int(endK.size())},
+              version - 2,
+          },
+      };
+      weaselab::ConflictSet::Result result[sizeof(reads) / sizeof(reads[0])];
+      cs->check(reads, result, sizeof(reads) / sizeof(reads[0]));
+      // for (int i = 0; i < sizeof(reads) / sizeof(reads[0]); ++i) {
+      //   if (result[i] != weaselab::ConflictSet::Commit) {
+      //     fprintf(stderr, "Unexpected conflict: [%s, %s) @ %" PRId64 "\n",
+      //             printable(reads[i].begin).c_str(),
+      //             printable(reads[i].end).c_str(), reads[i].readVersion);
+      //     abort();
+      //   }
+      // }
+    }
+    // Writes
+    {
+      weaselab::ConflictSet::WriteRange w;
+      auto k = numToKey(version);
+      w.begin.p = (const uint8_t *)k.data();
+      w.end.len = 0;
+      if (version % (kWindowSize / 2) == 0) {
+        for (int l = 0; l <= k.size(); ++l) {
+          w.begin.len = l;
+          cs->addWrites(&w, 1, version);
+        }
+      } else {
+        w.begin.len = k.size();
+        cs->addWrites(&w, 1, version);
+        int64_t beginN = version - kWindowSize + rand() % kWindowSize;
+        auto b = numToKey(beginN);
+        auto e = numToKey(beginN + 1000);
+        w.begin.p = (const uint8_t *)b.data();
+        w.begin.len = b.size();
+        w.end.p = (const uint8_t *)e.data();
+        w.end.len = e.size();
+        cs->addWrites(&w, 1, version);
+      }
+    }
+    // GC
+    cs->setOldestVersion(version - kWindowSize);
+    ++version;
+  }
+}
+
+// Adapted from getaddrinfo man page
+int getListenFd(const char *node, const char *service) {
+
+  struct addrinfo hints;
+  struct addrinfo *result, *rp;
+  int sfd, s;
+
+  memset(&hints, 0, sizeof(hints));
+  hints.ai_family = AF_UNSPEC;     /* Allow IPv4 or IPv6 */
+  hints.ai_socktype = SOCK_STREAM; /* stream socket */
+  hints.ai_flags = AI_PASSIVE;     /* For wildcard IP address */
+  hints.ai_protocol = 0;           /* Any protocol */
+  hints.ai_canonname = nullptr;
+  hints.ai_addr = nullptr;
+  hints.ai_next = nullptr;
+
+  s = getaddrinfo(node, service, &hints, &result);
+  if (s != 0) {
+    fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(s));
+    abort();
+  }
+
+  /* getaddrinfo() returns a list of address structures.
+     Try each address until we successfully bind(2).
+     If socket(2) (or bind(2)) fails, we (close the socket
+     and) try the next address. */
+
+  for (rp = result; rp != nullptr; rp = rp->ai_next) {
+    sfd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
+    if (sfd == -1) {
+      continue;
+    }
+
+    int val = 1;
+    setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
+
+    if (bind(sfd, rp->ai_addr, rp->ai_addrlen) == 0) {
+      break; /* Success */
+    }
+
+    close(sfd);
+  }
+
+  freeaddrinfo(result); /* No longer needed */
+
+  if (rp == nullptr) { /* No address succeeded */
+    fprintf(stderr, "Could not bind\n");
+    abort();
+  }
+
+  int rv = listen(sfd, SOMAXCONN);
+  if (rv) {
+    perror("listen()");
+    abort();
+  }
+
+  return sfd;
+}
+
+// HTTP response
+//
+std::string_view part1 =
+    "HTTP/1.1 200 OK \r\nContent-type: text/plain; version=0.0.4; "
+    "charset=utf-8; escaping=values\r\nContent-Length: ";
+// Decimal content length
+std::string_view part2 = "\r\n\r\n";
+// Body
+
+double toSeconds(timeval t) {
+  return double(t.tv_sec) + double(t.tv_usec) * 1e-6;
+}
+
+#ifdef __linux__
+#include <linux/perf_event.h>
+struct PerfCounter {
+  PerfCounter(int type, int config, const std::string &labels = {},
+              int groupLeaderFd = -1)
+      : labels(labels) {
+    struct perf_event_attr pe;
+
+    memset(&pe, 0, sizeof(pe));
+    pe.type = type;
+    pe.size = sizeof(pe);
+    pe.config = config;
+    pe.inherit = 1;
+    pe.exclude_kernel = 1;
+    pe.exclude_hv = 1;
+
+    fd = perf_event_open(&pe, 0, -1, groupLeaderFd, 0);
+    if (fd < 0 && errno != ENOENT && errno != EINVAL) {
+      perror(labels.c_str());
+    }
+  }
+
+  int64_t total() const {
+    int64_t count;
+    if (read(fd, &count, sizeof(count)) != sizeof(count)) {
+      perror("read instructions from perf");
+      abort();
+    }
+    return count;
+  }
+
+  PerfCounter(PerfCounter &&other)
+      : fd(std::exchange(other.fd, -1)), labels(std::move(other.labels)) {}
+  PerfCounter &operator=(PerfCounter &&other) {
+    fd = std::exchange(other.fd, -1);
+    labels = std::move(other.labels);
+    return *this;
+  }
+
+  ~PerfCounter() {
+    if (fd >= 0) {
+      close(fd);
+    }
+  }
+
+  bool ok() const { return fd >= 0; }
+  const std::string &getLabels() const { return labels; }
+  int getFd() const { return fd; }
+
+private:
+  int fd;
+  std::string labels;
+  static long perf_event_open(struct perf_event_attr *hw_event, pid_t pid,
+                              int cpu, int group_fd, unsigned long flags) {
+    int ret;
+
+    ret = syscall(SYS_perf_event_open, hw_event, pid, cpu, group_fd, flags);
+    return ret;
+  }
+};
+#endif
+
+int main(int argc, char **argv) {
+  if (argc != 3) {
+    goto fail;
+  }
+  {
+    int listenFd = getListenFd(argv[1], argv[2]);
+
+    weaselab::ConflictSet cs{0};
+    weaselab::ConflictSet::MetricsV1 *metrics;
+    int metricsCount;
+    cs.getMetricsV1(&metrics, &metricsCount);
+
+#ifdef __linux__
+    PerfCounter instructions{PERF_TYPE_HARDWARE, PERF_COUNT_HW_INSTRUCTIONS};
+    PerfCounter cycles{PERF_TYPE_HARDWARE, PERF_COUNT_HW_CPU_CYCLES, "",
+                       instructions.getFd()};
+
+    std::vector<PerfCounter> cacheCounters;
+    for (auto [id, idStr] : std::initializer_list<std::pair<int, std::string>>{
+             {PERF_COUNT_HW_CACHE_L1D, "l1d"},
+             {PERF_COUNT_HW_CACHE_L1I, "l1i"},
+             {PERF_COUNT_HW_CACHE_LL, "ll"},
+             {PERF_COUNT_HW_CACHE_DTLB, "dtlb"},
+             {PERF_COUNT_HW_CACHE_ITLB, "itlb"},
+             {PERF_COUNT_HW_CACHE_BPU, "bpu"},
+             {PERF_COUNT_HW_CACHE_NODE, "node"},
+         }) {
+      for (auto [op, opStr] :
+           std::initializer_list<std::pair<int, std::string>>{
+               {PERF_COUNT_HW_CACHE_OP_READ, "read"},
+               {PERF_COUNT_HW_CACHE_OP_WRITE, "write"},
+               {PERF_COUNT_HW_CACHE_OP_PREFETCH, "prefetch"},
+           }) {
+        int groupLeaderFd = -1;
+        for (auto [result, resultStr] :
+             std::initializer_list<std::pair<int, std::string>>{
+                 {PERF_COUNT_HW_CACHE_RESULT_MISS, "miss"},
+                 {PERF_COUNT_HW_CACHE_RESULT_ACCESS, "access"},
+             }) {
+          auto labels = "{id=\"" + idStr + "\", op=\"" + opStr +
+                        "\", result=\"" + resultStr + "\"}";
+          cacheCounters.emplace_back(PERF_TYPE_HW_CACHE,
+                                     id | (op << 8) | (result << 16), labels,
+                                     groupLeaderFd);
+          if (!cacheCounters.back().ok()) {
+            cacheCounters.pop_back();
+          } else {
+            if (groupLeaderFd == -1) {
+              groupLeaderFd = cacheCounters.back().getFd();
+            }
+          }
+        }
+      }
+    }
+#endif
+
+    auto w = std::thread{workload, &cs};
+
+    for (;;) {
+      struct sockaddr_storage peer_addr = {};
+      socklen_t peer_addr_len = sizeof(peer_addr);
+      const int connfd =
+          accept(listenFd, (struct sockaddr *)&peer_addr, &peer_addr_len);
+
+      std::string body;
+
+      rusage r;
+      getrusage(RUSAGE_SELF, &r);
+      body += "# HELP process_cpu_seconds_total Total user and system CPU time "
+              "spent in seconds.\n# TYPE process_cpu_seconds_total counter\n"
+              "process_cpu_seconds_total ";
+      body += std::to_string(toSeconds(r.ru_utime) + toSeconds(r.ru_stime));
+      body += "\n";
+      body += "# HELP process_resident_memory_bytes Resident memory size in "
+              "bytes.\n# TYPE process_resident_memory_bytes gauge\n"
+              "process_resident_memory_bytes ";
+      body += std::to_string(getCurrentRSS());
+      body += "\n";
+      body += "# HELP transactions_total Total number of transactions\n"
+              "# TYPE transactions_total counter\n"
+              "transactions_total ";
+      body += std::to_string(transactions.load(std::memory_order_relaxed));
+      body += "\n";
+#ifdef __linux__
+      body += "# HELP instructions_total Total number of instructions\n"
+              "# TYPE instructions_total counter\n"
+              "instructions_total ";
+      body += std::to_string(instructions.total());
+      body += "\n";
+      body += "# HELP cycles_total Total number of cycles\n"
+              "# TYPE cycles_total counter\n"
+              "cycles_total ";
+      body += std::to_string(cycles.total());
+      body += "\n";
+      body += "# HELP cache_event_total Total number of cache events\n"
+              "# TYPE cache_event_total counter\n";
+      for (const auto &counter : cacheCounters) {
+        body += "cache_event_total" + counter.getLabels() + " " +
+                std::to_string(counter.total()) + "\n";
+      }
+#endif
+
+      for (int i = 0; i < metricsCount; ++i) {
+        body += "# HELP ";
+        body += metrics[i].name;
+        body += " ";
+        body += metrics[i].help;
+        body += "\n";
+        body += "# TYPE ";
+        body += metrics[i].name;
+        body += " ";
+        body += metrics[i].type == metrics[i].Counter ? "counter" : "gauge";
+        body += "\n";
+        body += metrics[i].name;
+        body += " ";
+        body += std::to_string(metrics[i].getValue());
+        body += "\n";
+      }
+
+      auto len = std::to_string(body.size());
+      iovec iov[] = {
+          {(void *)part1.data(), part1.size()},
+          {(void *)len.data(), len.size()},
+          {(void *)part2.data(), part2.size()},
+          {(void *)body.data(), body.size()},
+      };
+      int written;
+      do {
+        written = writev(connfd, iov, sizeof(iov) / sizeof(iov[0]));
+      } while (written < 0 && errno == EINTR);
+      close(connfd);
+    }
+  }
+fail:
+  fprintf(stderr, "Expected ./%s <host> <port>\n", argv[0]);
+  return 1;
+}

SkipList.cpp

@@ -22,7 +22,10 @@
 
 #include "ConflictSet.h"
 #include "Internal.h"
+
+#include <algorithm>
 #include <span>
+#include <vector>
 
 std::span<const uint8_t> keyAfter(Arena &arena, std::span<const uint8_t> key) {
   auto result =
@@ -40,7 +43,7 @@ std::span<const uint8_t> copyToArena(Arena &arena,
 }
 
 using Version = int64_t;
-#define force_inline __attribute__((always_inline))
+#define force_inline inline __attribute__((always_inline))
 using StringRef = std::span<const uint8_t>;
 
 struct KeyRangeRef {
@@ -52,11 +55,124 @@ struct KeyRangeRef {
       : begin(begin), end(keyAfter(arena, begin)) {}
 };
 
-static thread_local uint32_t g_seed = 0;
+struct KeyInfo {
+  StringRef key;
+  bool begin;
+  bool write;
 
-static inline int skfastrand() {
-  g_seed = g_seed * 1664525L + 1013904223L;
-  return g_seed;
+  KeyInfo() = default;
+  KeyInfo(StringRef key, bool begin, bool write)
+      : key(key), begin(begin), write(write) {}
+};
+
+force_inline int extra_ordering(const KeyInfo &ki) {
+  return ki.begin * 2 + (ki.write ^ ki.begin);
+}
+
+// returns true if done with string
+force_inline bool getCharacter(const KeyInfo &ki, int character,
+                               int &outputCharacter) {
+  // normal case
+  if (character < ki.key.size()) {
+    outputCharacter = 5 + ki.key.begin()[character];
+    return false;
+  }
+
+  // termination
+  if (character == ki.key.size()) {
+    outputCharacter = 0;
+    return false;
+  }
+
+  if (character == ki.key.size() + 1) {
+    // end/begin+read/write relative sorting
+    outputCharacter = extra_ordering(ki);
+    return false;
+  }
+
+  outputCharacter = 0;
+  return true;
+}
+
+bool operator<(const KeyInfo &lhs, const KeyInfo &rhs) {
+  int i = std::min(lhs.key.size(), rhs.key.size());
+  int c = memcmp(lhs.key.data(), rhs.key.data(), i);
+  if (c != 0)
+    return c < 0;
+
+  // Always sort shorter keys before longer keys.
+  if (lhs.key.size() < rhs.key.size()) {
+    return true;
+  }
+  if (lhs.key.size() > rhs.key.size()) {
+    return false;
+  }
+
+  // When the keys are the same length, use the extra ordering constraint.
+  return extra_ordering(lhs) < extra_ordering(rhs);
+}
+
+bool operator==(const KeyInfo &lhs, const KeyInfo &rhs) {
+  return !(lhs < rhs || rhs < lhs);
+}
+
+struct SortTask {
+  int begin;
+  int size;
+  int character;
+  SortTask(int begin, int size, int character)
+      : begin(begin), size(size), character(character) {}
+};
+
+void sortPoints(std::vector<KeyInfo> &points) {
+  std::vector<SortTask> tasks;
+  std::vector<KeyInfo> newPoints;
+  std::vector<int> counts;
+
+  tasks.emplace_back(0, points.size(), 0);
+
+  while (tasks.size()) {
+    SortTask st = tasks.back();
+    tasks.pop_back();
+
+    if (st.size < 10) {
+      std::sort(points.begin() + st.begin, points.begin() + st.begin + st.size);
+      continue;
+    }
+
+    newPoints.resize(st.size);
+    counts.assign(256 + 5, 0);
+
+    // get counts
+    int c;
+    bool allDone = true;
+    for (int i = st.begin; i < st.begin + st.size; i++) {
+      allDone &= getCharacter(points[i], st.character, c);
+      counts[c]++;
+    }
+    if (allDone)
+      continue;
+
+    // calculate offsets from counts and build next level of tasks
+    int total = 0;
+    for (int i = 0; i < counts.size(); i++) {
+      int temp = counts[i];
+      if (temp > 1)
+        tasks.emplace_back(st.begin + total, temp, st.character + 1);
+      counts[i] = total;
+      total += temp;
+    }
+
+    // put in their places
+    for (int i = st.begin; i < st.begin + st.size; i++) {
+      getCharacter(points[i], st.character, c);
+      newPoints[counts[c]++] = points[i];
+    }
+
+    // copy back into original points array
+    for (int i = 0; i < st.size; i++)
+      points[st.begin + i] = newPoints[i];
+  }
 }
 
 static int compare(const StringRef &a, const StringRef &b) {
@@ -84,20 +200,24 @@ struct ReadConflictRange {
   }
 };
 
+static constexpr int MaxLevels = 26;
+
+struct RandomLevel {
+  explicit RandomLevel(uint32_t seed) : seed(seed) {}
+
+  int next() {
+    int result = __builtin_clz(seed | (uint32_t(-1) >> (MaxLevels - 1)));
+    seed = seed * 1664525L + 1013904223L;
+    return result;
+  }
+
+private:
+  uint32_t seed;
+};
+
 class SkipList {
 private:
-  static constexpr int MaxLevels = 26;
-
-  int randomLevel() const {
-    uint32_t i = uint32_t(skfastrand()) >> (32 - (MaxLevels - 1));
-    int level = 0;
-    while (i & 1) {
-      i >>= 1;
-      level++;
-    }
-    assert(level < MaxLevels);
-    return level;
-  }
+  RandomLevel randomLevel{0};
 
   // Represent a node in the SkipList. The node has multiple (i.e., level)
   // pointers to other nodes, and keeps a record of the max versions for each
@@ -295,18 +415,23 @@ public:
   }
   void swap(SkipList &other) { std::swap(header, other.header); }
 
-  void addConflictRanges(const Finger *fingers, int rangeCount,
-                         Version version) {
+  // Returns the change in the number of entries
+  int64_t addConflictRanges(const Finger *fingers, int rangeCount,
+                            Version version) {
+    int64_t result = rangeCount;
     for (int r = rangeCount - 1; r >= 0; r--) {
       const Finger &startF = fingers[r * 2];
       const Finger &endF = fingers[r * 2 + 1];
 
-      if (endF.found() == nullptr)
+      if (endF.found() == nullptr) {
+        ++result;
         insert(endF, endF.finger[0]->getMaxVersion(0));
+      }
 
-      remove(startF, endF);
+      result -= remove(startF, endF);
       insert(startF, version);
     }
+    return result;
   }
 
   void detectConflicts(ReadConflictRange *ranges, int count,
@@ -436,9 +561,10 @@ public:
   }
 
 private:
-  void remove(const Finger &start, const Finger &end) {
+  // Returns the number of entries removed
+  int64_t remove(const Finger &start, const Finger &end) {
     if (start.finger[0] == end.finger[0])
-      return;
+      return 0;
 
     Node *x = start.finger[0]->getNext(0);
 
@@ -447,17 +573,20 @@ private:
       if (start.finger[i] != end.finger[i])
         start.finger[i]->setNext(i, end.finger[i]->getNext(i));
 
+    int64_t result = 0;
     while (true) {
       Node *next = x->getNext(0);
       x->destroy();
+      ++result;
       if (x == end.finger[0])
         break;
       x = next;
     }
+    return result;
   }
 
   void insert(const Finger &f, Version version) {
-    int level = randomLevel();
+    int level = randomLevel.next();
     // std::cout << std::string((const char*)value,length) << " level: " <<
     // level << std::endl;
     Node *x = Node::create(f.value, level);
@@ -573,8 +702,6 @@ private:
   };
 };
 
-struct SkipListConflictSet {};
-
 struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
   Impl(int64_t oldestVersion)
       : oldestVersion(oldestVersion), newestVersion(oldestVersion),
@@ -602,10 +729,40 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
 
   void addWrites(const ConflictSet::WriteRange *writes, int count,
                  int64_t writeVersion) {
+    auto points = std::vector<KeyInfo>(count * 2);
+    Arena arena;
+
+    for (int r = 0; r < count; r++) {
+      points.emplace_back(StringRef(writes[r].begin.p, writes[r].begin.len),
+                          true, true);
+      points.emplace_back(
+          writes[r].end.len > 0
+              ? StringRef{writes[r].end.p, size_t(writes[r].end.len)}
+              : keyAfter(arena, points.back().key),
+          false, true);
+    }
+
+    sortPoints(points);
+
+    int activeWriteCount = 0;
+    std::vector<std::pair<StringRef, StringRef>> combinedWriteConflictRanges;
+    for (const KeyInfo &point : points) {
+      if (point.write) {
+        if (point.begin) {
+          activeWriteCount++;
+          if (activeWriteCount == 1)
+            combinedWriteConflictRanges.emplace_back(point.key, StringRef());
+        } else /*if (point.end)*/ {
+          activeWriteCount--;
+          if (activeWriteCount == 0)
+            combinedWriteConflictRanges.back().second = point.key;
+        }
+      }
+    }
+
     assert(writeVersion >= newestVersion);
     newestVersion = writeVersion;
-    Arena arena;
-    const int stringCount = count * 2;
+    const int stringCount = combinedWriteConflictRanges.size() * 2;
 
     const int stripeSize = 16;
     SkipList::Finger fingers[stripeSize];
@@ -614,23 +771,20 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
     StringRef values[stripeSize];
     int64_t writeVersions[stripeSize / 2];
     int ss = stringCount - (stripes - 1) * stripeSize;
+    int64_t entryDelta = 0;
     for (int s = stripes - 1; s >= 0; s--) {
       for (int i = 0; i * 2 < ss; ++i) {
-        const auto &w = writes[s * stripeSize / 2 + i];
-#if DEBUG_VERBOSE
-        printf("Write begin: %s\n", printable(w.begin).c_str());
-        fflush(stdout);
-#endif
-        values[i * 2] = {w.begin.p, size_t(w.begin.len)};
-        values[i * 2 + 1] = w.end.len > 0
-                                ? StringRef{w.end.p, size_t(w.end.len)}
-                                : keyAfter(arena, values[i * 2]);
-        keyUpdates += 3;
+        const auto &w = combinedWriteConflictRanges[s * stripeSize / 2 + i];
+        values[i * 2] = w.first;
+        values[i * 2 + 1] = w.second;
       }
       skipList.find(values, fingers, temp, ss);
-      skipList.addConflictRanges(fingers, ss / 2, writeVersion);
+      entryDelta += skipList.addConflictRanges(fingers, ss / 2, writeVersion);
       ss = stripeSize;
     }
+
+    // Run gc at least 200% the rate we're inserting entries
+    keyUpdates += std::max<int64_t>(entryDelta, 0) * 2;
   }
 
   void setOldestVersion(int64_t oldestVersion) {
@@ -640,7 +794,7 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
     int temp;
     std::span<const uint8_t> key = removalKey;
     skipList.find(&key, &finger, &temp, 1);
-    skipList.removeBefore(oldestVersion, finger, std::exchange(keyUpdates, 10));
+    skipList.removeBefore(oldestVersion, finger, std::exchange(keyUpdates, 0));
     removalArena = Arena();
     removalKey = copyToArena(
         removalArena, {finger.getValue().data(), finger.getValue().size()});
@@ -649,7 +803,7 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
   int64_t totalBytes = 0;
 
 private:
-  int64_t keyUpdates = 10;
+  int64_t keyUpdates = 0;
   Arena removalArena;
   std::span<const uint8_t> removalKey;
   int64_t oldestVersion;
@@ -702,6 +856,16 @@ void internal_destroy(ConflictSet::Impl *impl) {
 
 int64_t internal_getBytes(ConflictSet::Impl *impl) { return impl->totalBytes; }
 
+void internal_getMetricsV1(ConflictSet::Impl *impl,
+                           ConflictSet::MetricsV1 **metrics, int *count) {
+  *metrics = nullptr;
+  *count = 0;
+}
+
+double internal_getMetricValue(const ConflictSet::MetricsV1 *metric) {
+  return 0;
+}
+
 void ConflictSet::check(const ReadRange *reads, Result *results,
                         int count) const {
   internal_check(impl, reads, results, count);
@@ -718,6 +882,14 @@ void ConflictSet::setOldestVersion(int64_t oldestVersion) {
 
 int64_t ConflictSet::getBytes() const { return internal_getBytes(impl); }
 
+void ConflictSet::getMetricsV1(MetricsV1 **metrics, int *count) const {
+  return internal_getMetricsV1(impl, metrics, count);
+}
+
+double ConflictSet::MetricsV1::getValue() const {
+  return internal_getMetricValue(this);
+}
+
 ConflictSet::ConflictSet(int64_t oldestVersion)
     : impl(internal_create(oldestVersion)) {}
 

TestDriver.cpp

@@ -3,17 +3,68 @@
 #include <fstream>
 #include <sstream>
 
+#ifndef PERF_TEST
+#define PERF_TEST 0
+#endif
+
 int main(int argc, char **argv) {
   for (int i = 1; i < argc; ++i) {
     std::ifstream t(argv[i], std::ios::binary);
     std::stringstream buffer;
     buffer << t.rdbuf();
     auto str = buffer.str();
-    TestDriver<ConflictSet> driver{(const uint8_t *)str.data(), str.size()};
-    while (!driver.next())
-      ;
-    if (!driver.ok) {
-      abort();
+    Arbitrary arbitrary({(const uint8_t *)str.data(), str.size()});
+    TestDriver<ConflictSet, !PERF_TEST> driver1{arbitrary};
+    TestDriver<ConflictSet, !PERF_TEST> driver2{arbitrary};
+    bool done1 = false;
+    bool done2 = false;
+    for (;;) {
+      if (!done1) {
+        done1 = driver1.next();
+        if (!driver1.ok) {
+          abort();
+        }
+      }
+      if (!done2) {
+        done2 = driver2.next();
+        if (!driver2.ok) {
+          abort();
+        }
+      }
+      if (done1 && done2) {
+        break;
+      }
+    }
+
+    {
+      ConflictSet::MetricsV1 *metrics;
+      int metricsCount;
+      driver1.cs.getMetricsV1(&metrics, &metricsCount);
+      printf("#################### METRICS for ConflictSet 1 for %s "
+             "####################\n",
+             argv[i]);
+      for (int i = 0; i < metricsCount; ++i) {
+        printf("# HELP %s %s\n", metrics[i].name, metrics[i].help);
+        printf("# TYPE %s %s\n", metrics[i].name,
+               metrics[i].type == metrics[i].Counter ? "counter" : "gauge");
+        printf("%s %g\n", metrics[i].name, metrics[i].getValue());
+      }
+      puts("");
+    }
+    {
+      ConflictSet::MetricsV1 *metrics;
+      int metricsCount;
+      driver2.cs.getMetricsV1(&metrics, &metricsCount);
+      printf("#################### METRICS for ConflictSet 2 for %s "
+             "####################\n",
+             argv[i]);
+      for (int i = 0; i < metricsCount; ++i) {
+        printf("# HELP %s %s\n", metrics[i].name, metrics[i].help);
+        printf("# TYPE %s %s\n", metrics[i].name,
+               metrics[i].type == metrics[i].Counter ? "counter" : "gauge");
+        printf("%s %g\n", metrics[i].name, metrics[i].getValue());
+      }
+      puts("");
     }
   }
 }

aarch64-symbol-imports.txt

@@ -1,3 +1,5 @@
+__aarch64_ldadd8_relax
+__getauxval@GLIBC_2.17
 __stack_chk_fail@GLIBC_2.17
 __stack_chk_guard@GLIBC_2.17
 abort@GLIBC_2.17

apple-symbol-exports.txt

@@ -13,5 +13,7 @@ __ZN8weaselab11ConflictSetC2Ex
 __ZN8weaselab11ConflictSetD1Ev
 __ZN8weaselab11ConflictSetD2Ev
 __ZN8weaselab11ConflictSetaSEOS0_
+__ZNK8weaselab11ConflictSet12getMetricsV1EPPNS0_9MetricsV1EPi
 __ZNK8weaselab11ConflictSet5checkEPKNS0_9ReadRangeEPNS0_6ResultEi
 __ZNK8weaselab11ConflictSet8getBytesEv
+__ZNK8weaselab11ConflictSet9MetricsV18getValueEv

conflict_set_cxx_api_test.cpp

@@ -1,6 +1,7 @@
 #include "ConflictSet.h"
 
 #include <cassert>
+#include <cstdio>
 
 using namespace weaselab;
 
@@ -21,4 +22,14 @@ int main(void) {
   assert(result == ConflictSet::Conflict);
   int64_t bytes = cs.getBytes();
   assert(bytes > 0);
+
+  ConflictSet::MetricsV1 *metrics;
+  int metricsCount;
+  cs.getMetricsV1(&metrics, &metricsCount);
+  for (int i = 0; i < metricsCount; ++i) {
+    printf("# HELP %s %s\n", metrics[i].name, metrics[i].help);
+    printf("# TYPE %s %s\n", metrics[i].name,
+           metrics[i].type == metrics[i].Counter ? "counter" : "gauge");
+    printf("%s %g\n", metrics[i].name, metrics[i].getValue());
+  }
 }

corpus/0e410d4488defd877d2c9690a26970f57ab78b0c

@@ -1,4 +0,0 @@
-*
-
-
-