[boost] [quick_allocator] false sharing on SMP

From: Maxim Yegorushkin (maxim.yegorushkin_at_[hidden])
Date: 2005-08-25 02:52:58

Pavel Vozenilek asked to repost this here, so here it is:

http://groups.google.com/group/comp.lang.c++.moderated/msg/2b85fdcd20239a52

I just skimmed through boost/detail/quick_allocator.hpp and noticed
that quick_allocator causes false sharing on SMP. It happens when
several counters are allocated within the same cache line and those
counters are used by different processors, thus thrashing processors'
cache lines when the counter is written, even when the counter is used
by a single processor only.

More information about allocators and false sharing can be found in
papers included with Hoard allocator sources. http://hoard.org/

-- 
Maxim Yegorushkin