Re: SSD endurance calculations - Mailing list pgsql-performance

From Greg Smith
Subject Re: SSD endurance calculations
Date
Msg-id 4ECD0EE8.5030401@2ndQuadrant.com
Whole thread Raw
In response to SSD endurance calculations  (Christiaan Willemsen <cwillemsen@technocon.com>)
List pgsql-performance
On 11/21/2011 04:03 PM, Christiaan Willemsen wrote:
>
> Secondly, I also looked at the reliability figures of the Intel 320.
> They show 5 years of 20GB per day, meaning that it will hold up for
> about 200 days in our system. RAID 10 wil make 400 days of that, but
> this seems hardly a lot.. Am I missing something here?
>

The 320 series drives are not intended for things that write as heavily
as you do.  If your database is growing fast enough that you're going to
hit a terabyte in a short period of time, just cross that right off the
list of possibilities.  Intel's 710 series is the one aimed at your sort
of workload.

You can probably pull down the total write volume on your system by more
aggressively running VACUUM FREEZE shortly after new data is loaded.
PostgreSQL tends to write blocks even in INSERT-only tables several
times; forcing them to freeze early can eliminate several of them.

--
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD
PostgreSQL Training, Services, and 24x7 Support  www.2ndQuadrant.us


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