Should I use different HDD for Cassandra commit log and data? -


i started learning apache cassandra. in conf/cassandra.yaml noticed commitlog setting's comment following:

commit log. when running on magnetic hdd, should separate spindle data directories. if not set, default directory $cassandra_home/data/commitlog.

does mean should store commitlog in different hdd data? if yes, what's reason behind this? , happen if don't comply.

thanks.

that recommendation days of spinning-disk. due log-based storage engine, cassandra dependent on disk i/o. recommended have commit log , data directories on separate disks avoid potential bottleneck (latency) due heavy disk activity.

if using solid state drives (ssds, , cassandra should be) don't need worry this.

note: why using nas or san cassandra considered anti-pattern.


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