On Thu, Aug 27, 2026 at 12:16:56PM +0200, Thomas Huth wrote: > > Hi Denis! > > Please make sure to CC: the qtest maintainer (Fabiano Rosas) on series like > this. > > On 24/08/2026 22.06, Denis V. Lunev wrote: > > John reported ide-test dying at startup in the NetBSD VM: > > > > ERROR:../src/tests/qtest/ide-test.c:1260:main: assertion failed: > > (ret == 0) > > > > The hypothesys is that the ftruncate() of a 64 MiB scratch image. NetBSD > > mounts /tmp as a tmpfs sized at 25% of RAM and charges a file its full > > length themoment it is extended, so a sparse image is not free there and > > the call returns ENOSPC. The assert dates to 2013, nothing regressed. > > Does NetBSD have another file like /var/tmp that might be friendlier to > sparse files? If so, maybe that should be used instead? > > OTOH, our NetBSD VM in tests/vm/ uses 4G of RAM, so a temporary file with > just 64 MiB should really not be a problem...?
Or this is a concurrency scaling problem, or racing with another test that also uses stuff ? We hard code memory to 4 GB, but -smp we scale to "$NUM-CPUs / 2" for the "make vm-build-DIST" commands. IOW, regardless of whether QEMU is launched with -smp 1 or -smp 20, we only give it 4 GB to play with. We could be using a lot of RAM for concurrent build jobs leaving almost nothing for the tmpfs for the test. If we were that close to exhaustion I'd expected to see out of memory errors, but I'm unclear what NetBSD's behaviour is in this respect ? Maybe normal RAM usage can be pushed to swap (of which I see another 4 GB) while tmpfs can't be pushed to swap ? With regards, Daniel -- |: https://berrange.com ~~ https://hachyderm.io/@berrange :| |: https://libvirt.org ~~ https://entangle-photo.org :| |: https://pixelfed.art/berrange ~~ https://fstop138.berrange.com :|
