rocksdb/db/perf_context.cc
Haobo Xu d9dd2a1926 [RocksDB] Expose thread local perf counter for low overhead, per call level performance statistics.
Summary:
As title. No locking/atomic is needed due to thread local. There is also no need to modify the existing client interface, in order to expose related counters.

perf_context_test shows a simple example of retrieving the number of user key comparison done for each put and get call. More counters could be added later.

Sample output
./perf_context_test 1000000
==== Test PerfContextTest.KeyComparisonCount
Inserting 1000000 key/value pairs
...
total user key comparison get: 43446523
total user key comparison put: 8017877
max user key comparison get: 88939
avg user key comparison get:43

Basically, the current skiplist does well on average, but could perform poorly in extreme cases.

Test Plan: run perf_context_test <total number of entries to put/get>

Reviewers: dhruba

Differential Revision: https://reviews.facebook.net/D12225
2013-08-14 15:24:06 -07:00

13 lines
167 B
C++

#include "include/leveldb/perf_context.h"
namespace leveldb {
void PerfContext::Reset() {
user_key_comparison_count = 0;
}
__thread PerfContext perf_context;
}