recommended approach to obtain the size (in bytes) of a cache region

[rafaelcba]

Hi!

Is there any recommended approach to obtain the size (in bytes) of a cache region? Is there any java library I can use to get such metric?

[william.burns]

There are a few ways that are agnostic to your configuration. You could take a heap dump at a specific time and get an estimation based on some heap analysis tools. I normally like using Eclipse MAT [1]. You could also use JOL [2] to estimate the size of your objects and you can get a rough estimate from there.

If you want though Infinispan has a configuration option to enabled heap based eviction [3]. This way your cache should never get larger than around that size. This however requires you to also store your objects as either BINARY or OFF-HEAP which both serialize the object into bytes, which are significantly easier to count

[1] Eclipse Memory Analyzer Open Source Project

[2] OpenJDK: jol

[3] Infinispan 9.0 User Guide

[rafaelcba]

william.burns, many thanks for your reply.

I'll follow the Heap Dump approach and analyse using Eclipse MAT. We're using JDG 6.x version, I suspect the "heap based" config is only available in Infinispan 9 and above, Right? I didn't know about OpenJDK JOL tool. I'll certainly take a look on it.

Thanks o/

[william.burns]

No problem. Hope you get everything figured out.

Yes, unfortunately the memory based eviction requires Infinispan 8 or JDG 7 and off heap requires Infinispan 9.