Bug 16243 - Exception Maximum PB reference count exceeded.
Summary: Exception Maximum PB reference count exceeded.
Status: RESOLVED FIXED
Alias: None
Product: AutoBuilder
Classification: Infrastructure
Component: autobuilder (show other bugs)
Version: 6.0
Hardware: x86 Multiple
: Medium+ normal
Target Milestone: 6.1 M1
Assignee: Unassigned
QA Contact:
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Blocks:
 
Reported: 2026-04-12 01:53 UTC by Michael Halstead
Modified: 2026-05-19 18:32 UTC (History)
4 users (show)

See Also:
OS type for building Yocto: ---
Type of Regression: ---
Verified:
Documentation change: No (bug/feature does not impact docs)


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Comment 1 Michael Halstead 2026-04-12 01:56:34 UTC
I've added a cronjob that runs every three hours. It will restart any idle worker resetting the MAX_BROKER_REFS.

Ideally we'd track down why we are leaking refs and stop that.

Alternatively we could look into switching from pb to msgpack which does not have limits like this. 

Let's watch and see how this approach works out.
Comment 2 Michael Halstead 2026-05-19 17:07:07 UTC
BROKER_REF exhaustion appears to be fixed.

The restart job was causing a race between restarts and the job schedulers. I’ve moved it so that it starts 8 minutes after the hour, which should immediately resolve most of the issues.

We’re also going to update the restart script so that it pauses idle workers, waits 5 minutes, then checks state before taking further action.
Comment 3 Michael Halstead 2026-05-19 18:32:32 UTC
Script changes are up at https://git.yoctoproject.org/yocto-autobuilder-helper/diff/scripts/restart-if-idle.sh and this problem should be worked around indefinitely.