Re: raid10 write performance

[Karl Denninger <karl@xxxxxxxxxxxxx>]

Justin Graf wrote:

On 6/22/2010 4:31 AM, Grzegorz Jaśkiewicz wrote:
  

Would moving WAL dir to separate disk help potentially ?
   
    

Yes it can have a big impact.

WAL on a separate spindle will make a HUGE difference in performance.  TPS rates frequently double OR BETTER with WAL on a dedicated spindle.

Strongly recommended.

Be aware that you must pay CLOSE ATTENTION to your backup strategy if WAL is on a different physical disk.  Snapshotting the data disk where WAL is on a separate spindle and backing it up **WILL NOT WORK** and **WILL** result in an non-restoreable backup.

The manual discusses this but it's easy to miss.... don't or you'll get a NASTY surprise if something goes wrong.....

-- Karl

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