On Wednesday 01 of February 2012, Christoph Hellwig wrote: > This series improves handling of large number of dquots. It replaced > the direct recycling of dquots from the freelist with a shrinker, removes > the upper bound of dquots, and uses per-filesystem structures for all > quota state, including switching from a hash to a radix-tree for lookups. > > For repeated lookups of dquots out of a large pool I see improvements > betwen 50% and 500% compared to the previous code. All these tests > have been performed with Q_XQUOTASYNC already disabled as it would > change the result to much for both the old and new code. Thanks for this improvement! On 3.0.17 my script that executes ~130k of Q_XQUOTAGET lookups does it's job in 1m35s-1m45s and most of that is sys time. 3.3.0git + quota patchsets does the same thing in 23s and when cache gets hot it goes down to 9s-10s but sys time is only ~1s. Note that I'm using xfs_quota patched to avoid doing XQUOTASYNC, so that time is mostly XQUOTAGET also on 3.0.17 kernel. Of course the best test would be to test 3.3 without and with quota patchsets but I don't think there were any other improvements between 3.0 and 3.3 that could get such speed improvement for tons of XQUOTAGET calls. ps. my 3.3.0git kernel had this patchset and "[PATCH 0/3] include reservations in quota reportin" included 3.0.17 real 1m34.970s user 0m4.026s sys 1m25.081s real 1m45.365s user 0m4.106s sys 1m35.380s real 1m45.835s user 0m3.936s sys 1m35.854s real 1m45.608s user 0m4.023s sys 1m34.181s real 1m36.207s user 0m3.986s sys 1m26.068s real 1m45.969s user 0m4.016s sys 1m35.827s real 1m35.608s user 0m3.836s sys 1m25.534s real 1m45.882s user 0m3.986s sys 1m35.700s real 1m45.913s user 0m3.876s sys 1m36.064s real 1m45.702s user 0m4.010s sys 1m35.937s 3.3git + quota patchsets real 0m23.811s user 0m3.760s sys 0m1.373s real 0m9.712s user 0m3.740s sys 0m1.047s real 0m9.276s user 0m3.713s sys 0m1.113s real 0m9.880s user 0m3.870s sys 0m0.937s real 0m11.841s user 0m3.740s sys 0m1.077s real 0m10.086s user 0m3.760s sys 0m1.057s real 0m10.170s user 0m3.790s sys 0m1.063s real 0m9.457s user 0m3.686s sys 0m1.100s real 0m10.150s user 0m3.756s sys 0m1.073s real 0m9.331s user 0m3.810s sys 0m1.007s -- Arkadiusz Miśkiewicz PLD/Linux Team arekm / maven.pl http://ftp.pld-linux.org/ _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
