On Fri, 2019-04-05 at 06:54 +0000, mikko.rap...@bmw.de wrote: > On Fri, Apr 05, 2019 at 07:46:00AM +0100, > richard.pur...@linuxfoundation.org wrote: > > On Fri, 2019-04-05 at 06:16 +0000, mikko.rap...@bmw.de wrote: > > > On Thu, Apr 04, 2019 at 10:48:17PM +0100, Richard Purdie wrote: > > > > On Thu, 2019-04-04 at 18:00 +0200, Alexander Kanavin wrote: > > > > > As ptest-runner communicates with child processes via > > > > > pipe2(), > > > > > the corresponding channels are not attached to a pty. In that > > > > > situation stdio facilities like printf() or fwrite() are > > > > > fully > > > > > buffered. If a ptest would use them, without bothering > > > > > to fflush() the output, ptest-runner will only receive what > > > > > was written by the child ptest process after a buffer gets > > > > > filled. > > > > > If the unit tests are proceeding slowly, this may mean that > > > > > ptest-runner will erroneously timeout due to an apparent lack > > > > > of > > > > > 'signs of life' from the child process. > > > > > > > > > > stdbuf utility from coreutils adjusts the buffering to a > > > > > line- > > > > > buffered > > > > > one, and so ptest-runner will get the lines as soon as they > > > > > are > > > > > written. > > > > > > > > > > Signed-off-by: Alexander Kanavin <alex.kana...@gmail.com> > > > > > --- > > > > > utils.c | 7 ++----- > > > > > 1 file changed, 2 insertions(+), 5 deletions(-) > > > > > > > > I'm a little torn on this. I noticed some of the run-ptest > > > > scripts > > > > use > > > > "| sed -u" whilst the one you were seeing problems with uses "| > > > > sed" > > > > without -u. > > > > > > > > We may want to consider strongly recommending -u. I'm testing a > > > > patch > > > > with some tweaks like that in it... > > > > > > Please no. I'm running images without sed and using busybox sed > > > instead, and that > > > doesn't support -u. I'd rather be compatible with sed from > > > busybox to > > > keep changes > > > to images minimal (e.g. install of additional packages) before > > > executing ptests. > > > > The other alternative option being proposed is for ptest-runner to > > depend on coreutils which is worse? > > GNU sed does not come from coreutils but from sed recipe. > > Your call in the end. I just provided my point of view.
The original patch in this thread from Alex needs stdbuf which would add a coreutils depends to ptest-runner for everything as I understand it. > > I did test the -u option to sed in the openssh ptest runner and it > > did > > fix the problems we've been seeing. > > > > I'm open to other alternatives but the -u option to sed is looking > > like > > the best one we have right now. These bugs are making our testing > > of > > ptests effectively useless and unpredictable so this is a serious > > issue... > > Understood. I hope you could also add 'set -eux' to all ptest shell > scripts. Many of them seem to be missing shell script error handling > and failures like providing -u to busybox sed may go unnoticed. Patches would be welcome to help clean up some of these scripts. I feel like I'm fighting a lonely battle trying to get any of this to work at times :( The good news is the automated monitoring of the ptest results should catch problems like that as if a chunk of ptests "disappear", the new testing should quickly highlight that. (We should improve the scripts, we just also have another way to spot problems) Cheers, Richard -- _______________________________________________ yocto mailing list yocto@yoctoproject.org https://lists.yoctoproject.org/listinfo/yocto
