On Fri, Oct 05, 2018 at 03:02:16PM -0400, Jeff King wrote: > On Fri, Oct 05, 2018 at 08:39:04PM +0200, SZEDER Gábor wrote: > > > > It should still be a net win, since the total CPU seems to drop by a > > > factor of 3-4. > > > > Well, that's true when you have unlimited resources... :) or it's > > true even then, when I have just enough resources, but not much > > contention. After all, Coccinelle doesn't have to parse the same > > header files over and over again. However, on Travis CI, where who > > knows how many other build jobs are running next to our static > > analysis, it doesn't seem to be the case. > > > > On current master with an additional 'time' in front: > > > > time make --jobs=2 coccicheck > > <...> > > 695.70user 50.27system 6:27.88elapsed 192%CPU (0avgtext+0avgdata 91448maxresident)k > > 5976inputs+2536outputs (42major+18411888minor)pagefaults 0swaps > > > > https://travis-ci.org/szeder/git/jobs/437733874#L574 > > > > With this patch, but without -j2 to fit into 3GB: > > > > 960.50user 22.59system 16:23.74elapsed 99%CPU (0avgtext+0avgdata 1606156maxresident)k > > 5976inputs+1320outputs (26major+4548440minor)pagefaults 0swaps > > > > https://travis-ci.org/szeder/git/jobs/437734003#L575 > > > > Note that both the runtime and the CPU time increased. (and RSS, of > > course) > > I'm not sure what to make of those results. Was the jump in CPU _caused_ > by the patch, or does it independently fluctuate based on other things > happening on the Travis servers? > > I.e., in the second run, do we know that the time would not have > actually been worse with the first patch? Runtimes tend to fluctuate quite a bit more on Travis CI compared to my machine, but not this much, and it seems to be consistent so far. After scripting/querying the Travis CI API a bit, I found that from the last 100 static analysis build jobs 78 did actully run 'make coccicheck' [1], avaraging 470s for the whole build job, with only 4 build job exceeding the 10min mark. I had maybe 6-8 build jobs running this patch over the last 2-3 days, I think all of them were over 15min. (I restarted some of them, so I don't have separate logs for all of them, hence the uncertainty.) 1 - There are a couple of canceled build jobs, and we skip the build job of branches when they happen to match a tags.
