After installation of this fix, I haven't observed the deadlock anymore.

For those who haven't updated to 6.5.7 yet, Adobe has a new SP7 installation package with Hotfix-CQ-4312194-FELIX-6252 included in it. Makes upgrade faster and more stable. This is not publicly available (yet) but you can probably ask for it in a ticket.

Here are my observations after multiple rounds of testing:Fix seems to work, did not manage to replicate the issueDeployment of hotfix reloads a lot of bundles (go figure, it's felix) and takes significant amount of time/unavailabilityI had one case when the original issue managed to present itself ...

Thanks, looks like FELIX-6252 is what I'm observing in our environments. I'm raising support ticket for hotfix.

Can you check threaddumps. I've noticed AEM 6.5.7 hanging on following deadlock on my environments: java.lang.Thread.State: WAITING (on object monitor) at java.base@11.0.9/jdk.internal.misc.Unsafe.park(Native Method) - waiting to lock <0x1d24408f> (a java.util.concurrent.CountDownL...

OK, it looks like apis classifier is no longer required (https://repo.maven.apache.org/maven2/com/adobe/aem/uber-jar/6.5.6-1.0/uber-jar-6.5.6-1.0.jar)

Will apis without deprecations (like https://repo.adobe.com/nexus/content/repositories/public/com/adobe/aem/uber-jar/6.5.5/uber-jar-6.5.5-apis.jar) be available? I see only apis-with-deprecations (https://repo.maven.apache.org/maven2/com/adobe/aem/uber-jar/6.5.6-1.0/uber-jar-6.5.6-1.0-apis-with-depr...

Same problem here. POM for 6.5.6 https://repo.maven.apache.org/maven2/com/adobe/aem/uber-jar/6.5.6/uber-jar-6.5.6.pom looks nothing like the one from 6.5.5 https://repo.adobe.com/nexus/content/repositories/public/com/adobe/aem/uber-jar/6.5.5/uber-jar-6.5.5.pom