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Unified Diff: base/trace_event/heap_profiler_allocation_register.cc

Issue 2705023002: [Experimental, DO NOT LAND] bucket num 16
Patch Set: impl Created 3 years, 10 months ago
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Index: base/trace_event/heap_profiler_allocation_register.cc
diff --git a/base/trace_event/heap_profiler_allocation_register.cc b/base/trace_event/heap_profiler_allocation_register.cc
index 63d40611a6f6dcef24d2f524ff60ebf1994dfe62..fe42c991d39a235adc127a11fa91c3edaf2252c9 100644
--- a/base/trace_event/heap_profiler_allocation_register.cc
+++ b/base/trace_event/heap_profiler_allocation_register.cc
@@ -55,21 +55,6 @@ size_t AllocationRegister::BacktraceHasher::operator () (
return (total_value * 131101) >> 14;
}
-size_t AllocationRegister::AddressHasher::operator () (
- const void* address) const {
- // The multiplicative hashing scheme from [Knuth 1998]. The value of |a| has
- // been chosen carefully based on measurements with real-word data (addresses
- // recorded from a Chrome trace run). It is the first prime after 2^17. For
- // |shift|, 15 yield good results for both 2^18 and 2^19 bucket sizes.
- // Microbenchmarks show that this simple scheme outperforms fancy hashes like
- // Murmur3 by 20 to 40 percent.
- const uintptr_t key = reinterpret_cast<uintptr_t>(address);
- const uintptr_t a = 131101;
- const uintptr_t shift = 15;
- const uintptr_t h = (key * a) >> shift;
- return h;
-}
-
AllocationRegister::AllocationRegister()
: AllocationRegister(kAllocationCapacity, kBacktraceCapacity) {}
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