Hi Kristijonas,
To answer your questions:
1. It's still necessary to run full repair on a cluster on which
incremental repair is run periodically. The frequency of full repair is
more of an art than science. Generally speaking, the less reliable the
storage media, the more frequently full repair should be run. The
documentation on this topic is available here
<https://cassandra.apache.org/doc/stable/cassandra/operating/repair.html#incremental-and-full-repairs>
2. Run incremental repair for the first time on an existing cluster does
cause Cassandra to re-compact all SSTables, and can lead to disk usage
spikes. This can be avoided by following the steps mentioned here
<https://docs.datastax.com/en/cassandra-oss/3.0/cassandra/operations/opsRepairNodesMigration.html>
I hope that helps.
Cheers,
Bowen
On 02/02/2024 20:57, Kristijonas Zalys wrote:
Hi folks,
I am working on switching from full to incremental repair in Cassandra
v4.0.6 (soon to be v4.1.3) and I have a few questions.
1.
Is it necessary to run regular full repair on a cluster if I
already run incremental repair? If yes, what frequency would you
recommend for full repair?
2.
Has anyone experienced disk usage spikes while using incremental
repair? I have noticed temporary disk footprint increases of up to
2x (from ~15 GiB to ~30 GiB) caused by anti-compaction while
testing and am wondering how likely that is to happen in bigger
real world use cases?
Thank you all in advance!
Kristijonas
