Re: Sizing and striping log area

news.postgresql.org wrote:
> Are they archived like Oracle logs? Oracle writes to a log area and reads
> from the log area to generate archives. The archives are then used for
> recovery in case of corruption. This is important because reading from the
> drive throws off the head used for writing so seeking could be involved
> given this situation where reading and writing happen on the same drive
> concurrently. Oracle minimizes this by filling up, say, 500k of a certain
> disk before writing the logs to the next disk. Then it reads the 500k of
> logs and moves those to the archive. But if postgres doesn't use archives
> then this isn't an issue.
>
> Which leads me to another question... Does Postgres use archive logs and how
> does Postgres recover if it doesn't use archive logs? Or does it not
> recover as well as Oracle?

We sync() the info to disk and then recycle the logs. 7.4 will have
archive of logs, and hance point-in-time recovery.

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