On 07/11/2017 12:20 PM, Michal Hocko wrote: > 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. Yeah it was. -- 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>
