Add a simple point read/write workload to ServerBench

ServerBench.cpp

@@ -1,3 +1,4 @@
+#include <atomic>
 #include <errno.h>
 #include <netdb.h>
 #include <stdio.h>
@@ -14,22 +15,57 @@
 #include "ConflictSet.h"
 #include "third_party/nadeau.h"
 
+std::atomic<int64_t> transactions;
+
+constexpr int kBaseSearchDepth = 32;
+constexpr int kWindowSize = 10000000;
+
+std::basic_string<uint8_t> numToKey(int64_t num) {
+  std::basic_string<uint8_t> 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 = 0;
+  int64_t version = kWindowSize;
-  constexpr int kWindowSize = 45e6;
+  for (;; transactions.fetch_add(1, std::memory_order_relaxed)) {
-  for (;;) {
+    // Read
-    uint8_t buf[sizeof(version)];
+    {
-    int64_t be = __builtin_bswap64(version);
+      auto rv = version - kWindowSize + rand() % kWindowSize;
-    memcpy(buf, &be, sizeof(be));
+      auto k = numToKey(rv);
-    weaselab::ConflictSet::WriteRange w;
+      weaselab::ConflictSet::ReadRange r;
-    w.begin.p = buf;
+      r.begin.p = k.data();
-    w.begin.len = sizeof(buf);
+      r.begin.len = k.size();
-    w.end.len = 0;
+      r.end.len = 0;
-    cs->addWrites(&w, 1, version);
+      r.readVersion = rv;
-    ++version;
+      weaselab::ConflictSet::Result result;
-    if (version - kWindowSize >= 0) {
+      cs->check(&r, &result, 1);
-      cs->setOldestVersion(version - kWindowSize);
+      if (result != weaselab::ConflictSet::Commit) {
+        abort();
+      }
     }
+    // Write
+    {
+      weaselab::ConflictSet::WriteRange w;
+      auto k = numToKey(version);
+      w.begin.p = 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);
+      }
+    }
+    // GC
+    cs->setOldestVersion(version - kWindowSize);
+    ++version;
   }
 }
 
@@ -139,6 +175,11 @@ int main(int argc, char **argv) {
               "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";
 
       for (int i = 0; i < metricsCount; ++i) {
         body += "# HELP ";