Re: GiST index performance - Mailing list pgsql-performance
From | Matthew Wakeling |
---|---|
Subject | Re: GiST index performance |
Date | |
Msg-id | alpine.DEB.2.00.0906111810480.4337@aragorn.flymine.org Whole thread Raw |
In response to | Re: GiST index performance (Matthew Wakeling <matthew@flymine.org>) |
Responses |
Re: GiST index performance
Re: GiST index performance |
List | pgsql-performance |
Okay, I don't know quite what's happening here. Tom, perhaps you could advise. Running opannotate --source, I get this sort of stuff: /* * Total samples for file : ".../postgresql-8.4beta2/src/backend/access/gist/gistget.c" * * 6880 0.2680 */ and then: :static int64 :gistnext(IndexScanDesc scan, TIDBitmap *tbm) 81 0.0032 :{ /* gistnext total: 420087 16.3649 */ : Page p; The gistnext total doesn't seem to correspond to the amount I get by adding up all the individual lines in gistnest. Moreover, it is greater than the total samples attributed to the whole file, and greater than the samples assigned to all the lines where gistnext is called. However, yes it does seem like fmgr.c accounts for a large proportion of samples. Also, I still seem to be getting mcount, even after recompiling without --enable-profiling. CPU: Core 2, speed 1998 MHz (estimated) Counted CPU_CLK_UNHALTED events (Clock cycles when not halted) with a unit mask of 0x00 (Unhalted core cycles) count 100000 samples % image name app name symbol name 460213 17.9280 postgres postgres fmgr_oldstyle 420087 16.3649 postgres postgres gistnext 254975 9.9328 postgres postgres FunctionCall5 239572 9.3327 libc-2.9.so libc-2.9.so mcount 219963 8.5689 libc-2.9.so libc-2.9.so __mcount_internal 125674 4.8957 no-vmlinux no-vmlinux (no symbols) 117184 4.5650 postgres postgres gistdentryinit 106967 4.1670 btree_gist.so btree_gist.so gbt_int4_consistent 95677 3.7272 postgres postgres FunctionCall1 75397 2.9372 bioseg.so bioseg.so bioseg_gist_consistent 58832 2.2919 btree_gist.so btree_gist.so gbt_num_consistent 39128 1.5243 bioseg.so bioseg.so bioseg_overlap 33874 1.3196 libxul.so libxul.so (no symbols) 32008 1.2469 bioseg.so bioseg.so bioseg_gist_leaf_consistent 20890 0.8138 nvidia_drv.so nvidia_drv.so (no symbols) 19321 0.7527 bioseg.so bioseg.so bioseg_gist_decompress 17365 0.6765 libmozjs.so.1d libmozjs.so.1d (no symbols) Matthew -- A good programmer is one who looks both ways before crossing a one-way street. Considering the quality and quantity of one-way streets in Cambridge, it should be no surprise that there are so many good programmers there.
pgsql-performance by date: