Re: SSD Drives

On 04/03/2014 12:44 PM, Brent Wood wrote:
> Hi David,
>
> Does the RAID 1 array give any performance benefits over a single
> drive? I'd guess that writes may be slower, reads may be faster (if
> balanced) but data security is improved.

I've been looking into upgrading to SSD and wondering about RAID and
where to apply $$$ as well. In particular I'm curious about any
real-world PostgreSQL-oriented performance and data-protections advice
in the following areas:

1. With SSDs being orders of magnitude faster than spinning media, when
does the RAID controller rather than the storage become the bottleneck?

2. Do I need both BBU on the RAID *and* capacitor on the SSD or just on
one? Which one? I'm suspecting capacitor on the SSD and write-through on
the RAID.

2. Current thoughts on hardware vs. software RAID - especially since
many of the current SSD solutions plug straight into the bus.

3. Potential issues or conflicts with SSD-specific requirements like TRIM.

4. Manufacturers, models or technologies to seek out or avoid.

5. At what point do we consider the RAID controller an additional SPOF
that decreases instead of increases reliability?

6. Thoughts on "best bang for the buck?" For example, am I better off
dropping the RAID cards and additional drives and instead adding another
standby server?

Cheers,
Steve