Re: [Valgrind-developers] vgPlain_search_transtab

[Konstantin S. <kon...@gm...>]

2011/1/21 Julian Seward <js...@ac...>

>
> > > Can you send the results from --stats=yes ?  From that we can
> > > see the miss rate on VG_(tt_fast) and perhaps some other
> > > significant numbers.
> >
> > This?
> > --17273-- translate:            fast SP updates identified: 0 (   --%)
> > --17273-- translate:   generic_known SP updates identified: 0 (   --%)
> > --17273-- translate: generic_unknown SP updates identified: 0 (   --%)
> > --17273--     tt/tc: 14,941,381 tt lookups requiring 97,504,544 probes
> > --17273--     tt/tc: 14,941,381 fast-cache updates, 13 flushes
> > --17273--  transtab: new        292,328 (4,802,899 -> 45,933,795; ratio
> > 95:10) [0 scs]
> > --17273--  transtab: dumped     0 (0 -> ??)
> > --17273--  transtab: discarded  151 (1,798 -> ??)
> > --17273-- scheduler: 736,878,221 jumps (bb entries).
> > --17273-- scheduler: 9,067/37,285,698 major/minor sched events.
> > --17273--    sanity: 9068 cheap, 115 expensive checks.
> > --17273--    exectx: 769 lists, 0 contexts (avg 0 per list)
> > --17273--    exectx: 0 searches, 0 full compares (0 per 1000)
> > --17273--    exectx: 0 cmp2, 0 cmp4, 0 cmpAll
> > --17273--  errormgr: 0 supplist searches, 0 comparisons during search
> > --17273--  errormgr: 0 errlist searches, 0 comparisons during search
>
> Yes, this.  But .. are these the numbers from the run that had the
> unexpectedly high costs?


Yes (unless I am very much mistaken)
The profile was like this:
143136   51.6351  tsan-amd64-linux         tsan-amd64-linux
vgPlain_search_transtab
14517     5.2369  tsan-amd64-linux         tsan-amd64-linux
vgPlain_discard_translations
13297     4.7968  tsan-amd64-linux         tsan-amd64-linux
delete_translations_in_sector_eclass
12440     4.4876  tsan-amd64-linux         tsan-amd64-linux
ThreadSanitizerHandleTrace(int, TraceInfo*, unsigned long*)
11463     4.1352  tsan-amd64-linux         tsan-amd64-linux
vgPlain_run_innerloop__dispatch_unprofiled
10679     3.8524  anon (tgid:17291 range:0x404797a000-0x40525d2000)
tsan-amd64-linux         anon (tgid:17291 range:0x404797a000-0x40525d2000)
6528      2.3549  tsan-amd64-linux         tsan-amd64-linux
vgPlain_run_innerloop
6259      2.2579  tsan-amd64-linux         tsan-amd64-linux
invalidateFastCache



>  These numbers look normal to me: 736 million
> queries in the fast cache, 14.941 million misses and lookups in the
> main table (which is what VG_(search_transtab) does), and about 6
> hash probes per lookup (97,504,544 / 14,941,381).
>
> J
>