Re: slow update of index during insert/copy

"Scott Carey" <scott@richrelevance.com> writes:

> On Raid Controllers and Dev machines:
>
> For a dev machine the battery backup is NOT needed.
>
> Battery back up makes a _production_ system faster:  In production, data
> integrity is everything, and write-back caching is dangerous without a
> battery back up.
>
> So:
> Without BBU:   Write-through cache = data safe in power failure; Write back
> cache = not safe in power failure.
> With BBU :   Both modes are safe on power loss.

This could be read the wrong way. With a BBU it's not that you can run the
drives in write-back mode safely. It's that you can cache in the BBU safely.
The drives still need to have their write caches off (ie, in write-through
mode).

--
  Gregory Stark
  EnterpriseDB          http://www.enterprisedb.com
  Get trained by Bruce Momjian - ask me about EnterpriseDB's PostgreSQL training!