Hi, On 09/12/20 at 09:59 +0000, Simon McVittie wrote: > Control: retitle -1 gnome-photos: FTBFS on machines with more than 128 cores > > On Wed, 09 Dec 2020 at 09:35:05 +0100, Lucas Nussbaum wrote: > > During a rebuild of all packages in sid, your package failed to build > > on ppc64el. At the same time, it did not fail on amd64. > > > > > cd obj-powerpc64le-linux-gnu && LC_ALL=C.UTF-8 ninja -j160 -v > > Is this a 160-CPU machine?! (Or maybe 80- or 40-CPU with hyperthreading?)
It's 2 CPUs, 10 cores per CPU, 8 threads per core (https://en.wikipedia.org/wiki/POWER8) (So it's kind-of artificially large due to SMT) > > > Bail out! GLib-GObject-FATAL-WARNING: value "80" of type 'gint' is > > > invalid or out of range for property 'threads' of type 'gint' > > 80 does seem like a lot of threads, although it also seems weird to have an > arbitrary limit. > > libgegl has a GeglConfig singleton object with a "threads" property, whose > maximum value is an arbitrary constant GEGL_MAX_THREADS. > > gnome-photos sets "threads" to half the number of CPU cores available, > which is entirely reasonable for desktop-class hardware, but is not going > to work on something massively-parallel. > > Can you test-build a fix on similar hardware? Oddly enough I don't have a > machine with this many cores conveniently available :-) Sure! Lucas
