Backport !1690 “gs-plugin-loader: Run old-style plugin jobs in a custom thread pool” to gnome-44
Rather than running them in the thread pool shared between all GTask
s
in a process.
Using the GTask
thread pool can lead to livelocks if too many tasks
are running at once and all of them end up blocking on another operation
which also uses the GTask
thread pool. The combination of the
following factors can commonly reproduce this livelock problem:
-
GTask
thread pool only has 14 spaces. - DNS lookups via
GResolver
are run in theGTask
thread pool (unless using a version of GLib with glib!3397 (merged)). - All pending tasks depend on network I/O at some point, which is the case for most gnome-software jobs.
Eventually, this will be fixed by no longer using old-style plugin jobs:
new-style plugin jobs either execute asynchronously in the main thread
or run in plugin-specific worker threads, and hence don’t consume
unbounded GTask
resources. See #1472.
It’s going to take a few more cycles to finish off #1472, however, so in
the meantime we can eliminate the bottleneck on the constrained GTask
thread pool by running old-style plugin jobs in a custom thread pool.
Signed-off-by: Philip Withnall pwithnall@endlessos.org
Fixes: #2105 (closed)
Trivial backport of !1690 (merged) to gnome-44
.