This is an issue with jtreg Agent, but this could be a side effect of the test itself and the numerous re-use of Agent 18. Nothing recorded in the agent trace files.
This is filed under nio -- it can be redirected as appropriate

It might be prudent to run the test othervm --- in the event of future failures  it might capture more Agent details

There is another recent sighting in a private build and test


----------messages:(7/234)----------
command: testng EqualsCompareTest
reason: User specified action: run testng EqualsCompareTest 
started: Mon May 29 19:00:32 UTC 2023
Mode: agentvm
Agent id: 18
finished: Mon May 29 19:00:32 UTC 2023
elapsed time (seconds): 0.0

result: Error. Agent communication error: java.net.SocketException: Connection reset by peer; check console log for any additional details


test result: Error. Agent communication error: java.net.SocketException: Connection reset by peer; check console log for any additional details