Fwd: Re: using zstd cause high memtable switch count

[onmstester onmstester <on...@zoho.com.INVALID>]

No, i didn't backport that one.



Thank you


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============ Forwarded message ============
From: Kane Wilson <k...@raft.so>
To: <us...@cassandra.apache.org>
Date: Mon, 01 Mar 2021 03:18:33 +0330
Subject: Re: using zstd cause high memtable switch count
============ Forwarded message ============


Did you also backport https://github.com/apache/cassandra/commit/9c1bbf3ac913f9bdf7a0e0922106804af42d2c1e to still use LZ4 for flushing? I would be curious if this is a side effect of using zstd for flushing.
https://raft.so - Cassandra consulting, support, and managed services







On Sun, Feb 28, 2021 at 9:22 PM onmstester onmstester <ma...@zoho.com.invalid> wrote:

Hi,



I'm using 3.11.2, just add the patch for zstd and changed table compression from default (LZ4) to zstd with level 1 and chunk 64kb, everything is fine (disk usage decreased by 40% and CPU usage is almost the same as before), only the memtable switch count was changed dramatically; with lz4 it was less than 100 for a week, but with zstd it was more than 1000. I don't understand how its related.



P.S: Thank you guys for bringing zstd to Cassandra, it had a huge impact on my use-case by reducing almost 40% of costs, i wish i could have used it sooner (Although some sort of patch was already available for this feature 4 years ago).

Just find out that Hbase guys had zstd from 2017 and IMHO it would be good for Cassandra community to change its release policy to provide such features faster. 


Best Regards
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