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Re: better malloc strategies
David Boreham wrote:
Howard Chu wrote:
What's also interesting is that for Hoard, Umem, and Tcmalloc, the
multi-threaded query times are consistently about 2x slower than the
single-threaded case. The 2x slowdown makes sense since it's only a
dual-core CPU and it's doing 4x as much work. This kinda says that the
cost of malloc is overshadowed by the overhead of thread scheduling.
Is it possible that the block stride in the addresses returned by
malloc() is affecting
cache performance in the glibc case ?
If they are too close I think it is possible to thrash cache lines
That's a very good question, and I don't have an answer yet. I've been
working on some threading extensions for cachegrind so I can investigate
that. Unfortunately its existing infrastructure doesn't lend itself well
to tracking multiple caches, so that's been slow going.
-- Howard Chu
Chief Architect, Symas Corp. http://www.symas.com
Director, Highland Sun http://highlandsun.com/hyc
OpenLDAP Core Team http://www.openldap.org/project/