On Tue 11-07-17 08:26:40, Vlastimil Babka wrote: > On 07/11/2017 08:03 AM, Michal Hocko wrote: > > On Tue 11-07-17 09:58:42, Anshuman Khandual wrote: > >>> here. This is hardly something that would save many cycles in a > >>> relatively cold path. > >> > >> Though I have not done any detailed instruction level measurement, > >> there is a reduction in real and system amount of time to execute > >> the test with and without the patch. > >> > >> Without the patch > >> > >> real 0m2.100s > >> user 0m0.162s > >> sys 0m1.937s > >> > >> With this patch > >> > >> real 0m0.928s > >> user 0m0.161s > >> sys 0m0.756s > > > > Are you telling me that two if conditions cause more than a second > > difference? That sounds suspicious. > > It's removing also a call to get_unmapped_area(), AFAICS. That means a > vma search? Ohh, right. I have somehow missed that. Is this removal intentional? The changelog is silent about it. -- Michal Hocko SUSE Labs -- 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>
