To help optimize performance for different types of volumes, VxVM allows any one of several different types of read policy to be set on data plexes.
See "Changing the read policy for mirrored volumes" on page 298.
Use of mirroring and striping for improved performance shows an example where the read policy of the mirrored-stripe volume labeled
Vol is set to
prefer for the striped plex
Use of mirroring and striping for improved performance
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prefer policy distributes the load when reading across the otherwise lightly-used disks in
PL1, as opposed to the single disk in plex
HotVol is an example of a mirrored-stripe volume in which one data plex is striped and the other data plex is concatenated.)
To improve performance for read-intensive workloads, you can attach up to 32 data plexes to the same volume. However, this would usually be an ineffective use of disk space for the gain in read performance.