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? -- 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>
