Re: pg_xlog question

Pam Wampler <Pam_Wampler(at)taylorwhite(dot)com> writes:
> 1. what parameter tells postgress to always keep 7 files in the pg_xlog
> directory? (see below) --this is test database we
> are learning on. (and it seems everytime that I look at this directory there
> are always 7 entries there)

It's basically 2 * checkpoint_segments + 1. See
http://www.ca.postgresql.org/users-lounge/docs/7.2/postgres/wal-configuration.html

> 2. What happens when the files increment and can no longer increment to a
> higher number (the file name)?

Trouble, which is why we use a 64-bit counter.

> 3. Is there a way to "reset" the number so that this won't happen?

initdb. However, you're not gonna have to worry about it in your
lifetime. Do the math...

regards, tom lane