On Wed, 16 Jan 2008, Matthew Wilcox wrote: > We tested 2.6.24-rc5 + 76be895001f2b0bee42a7685e942d3e08d5dd46c > > For 2.6.24-rc5 before that patch, slub had a performance penalty of > 6.19%. With the patch, slub's performance penalty was reduced to 4.38%. > This is great progress. Can you think of anything else worth trying?
Ahhh.. Good to hear that the issue on x86_64 gets better. I am still waiting for a test with the patchset that I did specifically to address your regression: http://lkml.org/lkml/2007/10/27/245 (where I tried to come up with an in kernel benchmark that exposes the issue even more)? It is much more likely now that this patchset in mm addresses your regression since the hackbench performance improvement fix already reduce it partially. 2.6.25 will add the performance enhancements for the free patch that I hope will address your issues. In addition the fastpath was reworked. See the patch mentioned above. 2.6.26 (hopefully) will remove the per cpu array lookups that are currently necessary on x86 and other platforms through improvements to the way that percpu data is handled. That leads to further fastpath improvements. There are also ways to optimize the partial block handling further by f.e. switching the percpu slab on free in order to have a higher fastpath rate. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
