On Fri, Jun 10, 2016 at 11:02:38PM +0200, Julia Lawall wrote: > > > On Fri, 10 Jun 2016, Luis R. Rodriguez wrote: > > > Enable indexing optimizations heuristics. Coccinelle has > > support to make use of its own enhanced "grep" mechanisms > > instead of using regular grep for searching code 'coccigrep', > > in practice though this seems to not perform better than > > regular grep however its expected to help with some use cases > > so we use that if you have no other indexing options in place > > available. > > > > Since git has its own index, support for using 'git grep' has been > > added to Coccinelle, that should on average perform better than > > using the internal cocci grep, and regular grep. Lastly, Coccinelle > > has had support for glimpseindex for a long while, however the > > tool was previously closed source, its now open sourced, and > > provides the best performance, so support that if we can detect > > you have a glimpse index. > > > > These tests have been run on an 8 core system: > > > > Before: > > > > $ export COCCI=scripts/coccinelle/free/kfree.cocci > > $ time make coccicheck MODE=report > > > > Before this patch with no indexing or anything: > > > > real 16m22.435s > > user 128m30.060s > > sys 0m2.712s > > > > Using coccigrep (after this patch if you have no .git): > > > > real 16m27.650s > > user 128m47.904s > > sys 0m2.176s > > > > If you have .git and therefore use gitgrep: > > > > real 16m21.220s > > user 129m30.940s > > sys 0m2.060s > > > > And if you have a .glimpse_index: > > > > real 16m14.794s > > user 128m42.356s > > sys 0m1.880s > > I don't see any convincing differences in these times. > > I believe that Coccinelle's internal grep is always used, even with no > option.
Ah that would explain it. This uses coccinelle 1.0.5, is the default there to use --use-coccigrep if no other index is specified ? > I'm puzzled why glimpse gives no benefit. Well, slightly better. Luis _______________________________________________ Cocci mailing list Cocci@systeme.lip6.fr https://systeme.lip6.fr/mailman/listinfo/cocci