Re: pg_dump docs should mention TMPDIR

On 2006-05-03, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Mark Stosberg <mark(at)summersault(dot)com> writes:
>> A suggested addition to the pg_dump docs:
>> This would be an extension to the documentation for the "tar" format:
>
>> The tar format needs some space to create temporary files. By default
>> "/tmp" is used. On systems with small "/tmp" partitions, set the
>> "TMPDIR" environment variable to a location with more space, such as
>> "/usr/tmp".
>
> There is no reference to TMPDIR in the pg_dump code. It may be that
> tmpfile() pays attention to such an environment variable on your
> machine, but there's nothing about it in the Single Unix Spec.

Yes, on FreeBSD "man tmpfile()" documents the use of TMPDIR.

If TMPDIR isn't being respected globally, perhaps there /should/ be
logic in the code to make that so. Even on fairly modern FreeBSD
installs, sometimes "/tmp" only has 256 MB of room. There really should
be a reliable way to specify a different temporary directory.

>> Also, I would like it if the pg_dump docs more assertively recommended
>> one of the "tar" or "custom" formats. They seem very similiar.
>
> Yeah. I think it should specifically recommend custom format. The only
> reason for using tar format would be if you want to process the file
> later with something other than pg_restore.

Thanks for the recommendation.

Is that any concern that over time newer pg_restore's won't read old
"custom" formats? That would be my only worry-- that the data would be
locked in a binary format which becomes unsupported.

Mark