Thanks John! We see 13.5% improvement in total runtime using r. According to oprofile the time spent in do_cnt is down from 20% to 4.3%. Unfortunately I don¹t have call counts since I¹m not using an instrumented profiler (just pc sampling). gprof was giving strange results because my application is multi threaded.
On 12/16/14, 9:29 PM, "K. John Wu" <[email protected]> wrote: >Hi, Steven, > >Based on guess that the problem was caused by a solution implemented >to address a thread-safety issue raised earlier this year (Change made >on 2014/08/06). I have implemented a change to hopefully resolve this >in a slightly better way this way. The change is in SVN revision 788. > Please give it a try when you get the chance. > >Thanks, > >John > > >On 12/15/14 5:57 PM, Enns, Steven wrote: >> Trying the mailing list >> >> From: <Enns>, "Enns, Steven" <[email protected] <mailto:[email protected]>> >> Date: Tuesday, December 9, 2014 at 11:20 AM >> To: "K. John Wu" <[email protected] <mailto:[email protected]>> >> Subject: question about doEvaluate >> >> Hi John, >> >> I am profiling my application and noticed 20% of my time is spent in >> ibis::query::doEvaluate() -> ibis::bitvector::cnt() -> >> ibis::bitvector::do_cnt() >> >> case ibis::qExpr::LOGICAL_OR: { >> ierr = doEvaluate(term->getLeft(), mask, ht); >> if (ierr >= 0 && ht.cnt() < mask.cnt()) { >> ibis::bitvector b1; >> ierr = doEvaluate(term->getRight(), mask, b1); >> if (ierr > 0) >> ht |= b1; >> if (ierr >= 0) >> ierr = ht.sloppyCount(); >> } >> break; >> } >> >> * Is this an optimization? >> * What is the purpose of the bitvector called Œmask'? >> * What does it mean to compare ht.cnt() to mask.cnt()? >> * ibis::bitvector::cnt() caches the result in ibis::bitvector::nset >> and ibis::bitvector::nbit. Should this call to ht.cnt() result in >> a 'cache hit'? It seems ht changes at every node of the query so >> 'cache miss' seems reasonable. >> >> >> Thanks! >> >> >> _______________________________________________ >> FastBit-users mailing list >> [email protected] >> https://hpcrdm.lbl.gov/cgi-bin/mailman/listinfo/fastbit-users >> >_______________________________________________ >FastBit-users mailing list >[email protected] >https://hpcrdm.lbl.gov/cgi-bin/mailman/listinfo/fastbit-users _______________________________________________ FastBit-users mailing list [email protected] https://hpcrdm.lbl.gov/cgi-bin/mailman/listinfo/fastbit-users
