On Thu, 15 May 2014, Madhavan Srinivasan wrote: > > Hi Ingo, > > Do you have any comments for the latest version of the patchset. If > not, kindly can you pick it up as is. > > > With regards > Maddy > > > Kirill A. Shutemov with 8c6e50b029 commit introduced > > vm_ops->map_pages() for mapping easy accessible pages around > > fault address in hope to reduce number of minor page faults. > > > > This patch creates infrastructure to modify the FAULT_AROUND_ORDER > > value using mm/Kconfig. This will enable architecture maintainers > > to decide on suitable FAULT_AROUND_ORDER value based on > > performance data for that architecture. First patch also defaults > > FAULT_AROUND_ORDER Kconfig element to 4. Second patch list > > out the performance numbers for powerpc (platform pseries) and > > initialize the fault around order variable for pseries platform of > > powerpc. Sorry for not commenting earlier - just reminded by this ping to Ingo. I didn't study your numbers, but nowhere did I see what PAGE_SIZE you use. arch/powerpc/Kconfig suggests that Power supports base page size of 4k, 16k, 64k or 256k. I would expect your optimal fault_around_order to depend very much on the base page size. Perhaps fault_around_size would provide a more useful default? Hugh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>