Re: Reliability with RAID 10 SSD and Streaming Replication

On Thu, May 16, 2013 at 9:46 AM, Cuong Hoang <climbingrose(at)gmail(dot)com> wrote:
> Hi all,
>
> Our application is heavy write and IO utilisation has been the problem for
> us for a while. We've decided to use RAID 10 of 4x500GB Samsung 840 Pro for
> the master server. I'm aware of write cache issue on SSDs in case of power
> loss. However, our hosting provider doesn't offer any other choices of SSD
> drives with supercapacitor. To minimise risk, we will also set up another
> RAID 10 SAS in streaming replication mode. For our application, a few
> seconds of data loss is acceptable.
>
> My question is, would corrupted data files on the primary server affect the
> streaming standby? In other word, is this setup acceptable in terms of
> minimising deficiency of SSDs?

Data corruption caused by sudden power event on the master will not
cross over. Basically with this configuration you must switch over to
the standby in that case. Corruption caused by other issues, say a
faulty drive, will transfer over however. Block checksum feature of
9.3 as a strategy to reduce the risk of that class of issue.

merlin