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Comment by noelwelsh | Hacker News Reader

I haven't spent much time in the world of JVM tuning, but if latency is your main concern the relatively new ZGC should be your jam: https://wiki.openjdk.java.net/display/zgc/Main

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Yep. ZGC will soon offer worst-case pauses of <1ms (it's around 2-3 now).

This is interesting; I would really appreciate source on this.

Also, what are the parameters for this assessment (cpu count, cpu frequency, memory frequency, heap size, object demography etc)?

There's material here (talks, slides etc.):

https://wiki.openjdk.java.net/display/zgc/

I think the plan is to reach the 1ms worst-case goal in 15 or 16.

Is ZGC production ready? Specially with JVM11?

It will be declared non-experimental in 15, but people are running it in production on 14. GCs, and performance in general, tend to improve quite significantly between releases.

Great news. How about the rival Shenandoah GC?

They're both non-experimental in 15: https://openjdk.java.net/projects/jdk/15/

I haven't used it myself but I have heard others do so with success. It looks like JDK14 has some significant improvements to ZGC so I would try to run on that if possible.

I might do some performance tests of my own soon.

For how much % less of throughput tough?

You can take a look at the slides and talks here: https://wiki.openjdk.java.net/display/zgc/

Thanks! Nice to know they added support for class data sharing in jvm 15!

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