Will ZGC Allocation Stall block the whole application during the whole GC phase in JDK17?

[Roy Zhang]

Dear ZGC experts,

We are using ZGC on JDK17 (AWS JDK17, OpenJDK 64-Bit Server VM
(17.0.10+8-LTS) for linux-amd64 JRE (17.0.10+8-LTS), built on Feb  6 2024
19:58:14 by "jenkins" with gcc 7.3.1 20180303 (Red Hat 7.3.1-5)), from JFR,
we found there are several consecutive Allocation Stall event, high GC
duration (8s+) but low pause(<< 1ms), and our health check failed (2s
timeout) during that period, no safepoint begin(default 10ms threshold) JFR
event.

I am curious, will ZGC allocation stall  block the application to serve
health check requests during the whole phase (8s+)?  Otherwise I can't
understand why the health check will fail?

Really appreciate ur great help in advance!

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Thanks
Roy
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