On 10/14/2012 11:00 AM, John R Pierce wrote:
> On 10/13/12 7:13 PM, Craig Ringer wrote:
>>
>> * Use a good quality hardware RAID controller with a battery backup
>> cache unit if you're using spinning disks in RAID. This is as much for
>> performance as reliability; a BBU will make an immense difference to
>> database performance.
>
> a comment on this one.... I have some test servers with lots of SAS
> and/or SATA drives on controllers like LSI Logic 9261-8i, with 512MB or
> 1GB battery-backed cache. I can configure the controller for JBOD
> and use linux mdraid raid10 and get the same performance as the
> controllers native raid10, as long as the write-back cache is
> enabled. disable the writeback cache, and you might as well be using
> SATA JBOD.
Yeah, without the write-back cache you don't gain much. I run a couple
of DBs on plain old `md` RAID and I'm actually quite happy with it.
I've expanded this into a blog post and improved that section there.
http://blog.ringerc.id.au/2012/10/avoiding-postgresql-database-corruption.html
Comments appreciated.
--
Craig Ringer
