Repository navigation
Fix SSH agents hanging on Java 17 (#32) - #33
Merged
Merged
Conversation
…#32) With the SSH Build Agents launcher, the agent's standard output is the remoting channel. JvmDowngrader's loggers write to the System.out they see when its Java agent starts, so a log line from them went into the channel and the agent hung after 'channel started'. agent8's Java agent now points System.out at standard error while JvmDowngrader starts, and Main puts it back before remoting starts. CI: the SSH launcher job also runs on Java 17.
This was referenced Nov 2, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Before: with the SSH Build Agents launcher, an agent on Java 17 hangs after
channel startedand never comes online (#32). Java 8 agents and inbound agents are not affected.After: the agent comes online and runs builds on Java 17 over SSH.
With the SSH launcher, the agent's standard output is the remoting channel. JvmDowngrader's loggers write to the
System.outthey see when its Java agent starts, so a log line from them went into the channel and the controller's reader waited mid-chunk for data that never came.How: agent8's Java agent, which starts before JvmDowngrader's, points
System.outat standard error;Mainputs the real standard output back before remoting starts. CI: the SSH launcher job also runs on Java 17 (test/ssh.shskips the signed provider checks there, since they use the Java 8 extension directory). Reproduced and verified on a temporary branch against Jenkins 2.580.1: hang before, agent online and freestyle build passing after.Refs #32 (left open until the reporter confirms on Solaris)