GC duration and pause time grow linearly

[Kirill Ilyukhin]

Dear Shenandoah developers,

Please look at the attached images, these are charts built by cgeasy.io for
my GC log. GC/pause time grows as if it were a linear function of JVM
uptime. Is this an expected behavior? I am not complaining, performance is
good enough, but GC/pause time trend looks a bit suspicious.

This JVM is a standby instance of Tomcat 9.0.22 as a Windows service, doing
almost nothing. Most of GC are time-triggered, every 5 minutes.
Please let me know if you need more information.

Java:
openjdk version "13-internal" 2019-09-17
OpenJDK Runtime Environment (build 13-internal+0-adhoc..build)
OpenJDK 64-Bit Server VM (build 13-internal+0-adhoc..build, mixed mode,
sharing)

Command line arguments:
-XX:+UseStringDeduplication
-Xlog:gc*,safepoint:file=\logs\gc.%t.log:time,level,tags:filecount=1000,filesize=100M
-XX:+UnlockExperimentalVMOptions
-XX:+UseShenandoahGC
-XX:+AlwaysPreTouch
-Xms1024m
-Xmx1024m

OS:
Windows Server 2008 R2, version 6.2 (build 7601: Service Pack 1)

Thanks a lot,
Kirill


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