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README.md

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+A data structure for optimistic concurrency control on ranges of bitwise-lexicographically-ordered keys.
+
+Intended to replace FoundationDB's skip list.
+
+# FoundationDB's benchmark
+
+## Skip list
+
+```
+New conflict set: 4.189 sec
+                  0.298 Mtransactions/sec
+                  1.194 Mkeys/sec
+Detect only:      3.990 sec
+                  0.313 Mtransactions/sec
+                  1.253 Mkeys/sec
+Skiplist only:    2.849 sec
+                  0.439 Mtransactions/sec
+                  1.755 Mkeys/sec
+Performance counters:
+               Build: 0.0913
+                 Add: 0.0998
+              Detect: 3.99
+              D.Sort: 0.808
+           D.Combine: 0.0309
+         D.CheckRead: 1.67
+   D.CheckIntraBatch: 0.0305
+        D.MergeWrite: 1.18
+      D.RemoveBefore: 0.265
+```
+
+## Radix tree (this implementation)
+
+```
+New conflict set: 2.965 sec
+                  0.422 Mtransactions/sec
+                  1.686 Mkeys/sec
+Detect only:      2.761 sec
+                  0.453 Mtransactions/sec
+                  1.811 Mkeys/sec
+Skiplist only:    1.580 sec
+                  0.791 Mtransactions/sec
+                  3.165 Mkeys/sec
+Performance counters:
+               Build: 0.0902
+                 Add: 0.107
+              Detect: 2.76
+              D.Sort: 0.809
+           D.Combine: 0.0309
+         D.CheckRead: 0.658
+   D.CheckIntraBatch: 0.0294
+        D.MergeWrite: 0.921
+      D.RemoveBefore: 0.305
+```
+
+# Our benchmark
+
+|               ns/op |                op/s |    err% |     total | benchmark
+|--------------------:|--------------------:|--------:|----------:|:----------
+|              263.10 |        3,800,889.33 |    1.6% |      0.64 | `skip list (point reads)`
+|              256.36 |        3,900,800.96 |    1.7% |      0.61 | `skip list (prefix reads)`
+|              526.95 |        1,897,714.85 |    1.6% |      1.23 | `skip list (range reads)`
+|              546.54 |        1,829,676.97 |    0.5% |      1.31 | `skip list (point writes)`
+|              539.23 |        1,854,511.73 |    0.5% |      1.29 | `skip list (prefix writes)`
+|              266.68 |        3,749,799.99 |    0.6% |      0.65 | `skip list (range writes)`
+|               18.31 |       54,612,706.60 |    0.4% |      0.04 | `radix tree (point reads)`
+|               48.78 |       20,498,870.77 |    0.2% |      0.12 | `radix tree (prefix reads)`
+|              347.16 |        2,880,474.86 |    0.9% |      0.83 | `radix tree (range reads)`
+|               34.80 |       28,734,706.67 |    3.6% |      0.09 | `radix tree (point writes)`
+|               70.34 |       14,216,970.16 |    1.4% |      0.17 | `radix tree (prefix writes)`
+|               82.41 |       12,134,555.86 |    1.0% |      0.20 | `radix tree (range writes)`