Subject: Re: [boost] [lockfree::fifo] Review
From: Tim Blechmann (tim_at_[hidden])
Date: 2009-12-20 10:36:50
> Well, IMO, it should perform better because the producer and consumer are
> not thrashing each other wrt the head and tail indexes.
the performance difference is almost the same.
current implementation:
Performance counter stats for
'workspace/boost_lockfree/bin.v2/libs/lockfree/test/ringbuffer_test.test/gcc-4.4.1/release/threading-multi/ringbuffer_test':
104843.459702 task-clock-msecs # 1.919 CPUs
86507 context-switches # 0.001 M/sec
100 CPU-migrations # 0.000 M/sec
2123 page-faults # 0.000 M/sec
292926371337 cycles # 2793.940 M/sec
139203486138 instructions # 0.475 IPC
3829638652 cache-references # 36.527 M/sec
19789409 cache-misses # 0.189 M/sec
31762728722 branches # 302.954 M/sec
1669597777 branch-misses # 15.925 M/sec
54.643822949 seconds time elapsed
your proposed implementation (with cache line padding):
Performance counter stats for
'workspace/boost_lockfree/bin.v2/libs/lockfree/test/ringbuffer_test2.test/gcc-4.4.1/release/threading-multi/ringbuffer_test2':
104827.826694 task-clock-msecs # 1.922 CPUs
84196 context-switches # 0.001 M/sec
196 CPU-migrations # 0.000 M/sec
2135 page-faults # 0.000 M/sec
292892624370 cycles # 2794.035 M/sec
149885017189 instructions # 0.512 IPC
3301119985 cache-references # 31.491 M/sec
20729054 cache-misses # 0.198 M/sec
33378354235 branches # 318.411 M/sec
1685405757 branch-misses # 16.078 M/sec
54.527086724 seconds time elapsed
cheers, tim
-- tim_at_[hidden] http://tim.klingt.org Desperation is the raw material of drastic change. Only those who can leave behind everything they have ever believed in can hope to escape. William S. Burroughs