cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Jeremy Hanna (JIRA)" <>
Subject [jira] [Updated] (CASSANDRA-12619) Improve JBOD throughput
Date Mon, 15 Jan 2018 19:45:01 GMT


Jeremy Hanna updated CASSANDRA-12619:
    Labels: jbod-aware-compaction performance  (was: performance)

> Improve JBOD throughput
> -----------------------
>                 Key: CASSANDRA-12619
>                 URL:
>             Project: Cassandra
>          Issue Type: Improvement
>            Reporter: Natale Galioto
>            Priority: Major
>              Labels: jbod-aware-compaction, performance
>             Fix For: 4.x
> Nodes with spinning disks have very limited throughputs during compactions. This is mainly
due to [][CASSANDRA-6696] where each SSTable
got "sticked" to one data directory only. In order to increase the performance during compactions,
reads and writes should always happen on different directories, and a single data directory
(for both reads or writes) should be used by no more than one compactor at time. The current
throughput of a single spinning disk can get as low as 20MB/s due to r/w seeks penalties,
but a compaction between two different spindles could easily get 100MB/s or more throughput.
Since 6696 requires sstables to always be on the same data directory, even a compaction between
two different data directory and then a "brutal" copy back to the "appropriate" directory
could get an overall throughput of 50MB/s. Another option would be to let SStables "float"
between two data directories only, and "switch" between them at every compaction.

This message was sent by Atlassian JIRA

To unsubscribe, e-mail:
For additional commands, e-mail:

View raw message