Re: inconvenient compression options in pg_basebackup

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter_e@gmx.net>
Cc: Magnus Hagander <magnus@hagander.net>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2011-05-26T21:11:12Z
Lists: pgsql-hackers
Peter Eisentraut <peter_e@gmx.net> writes:
> On tor, 2011-05-26 at 16:54 -0400, Tom Lane wrote:
>> But if you want to take such an extension into account right now,
>> maybe we ought to design that feature now.  What are you seeing it as
>> looking like?
>> 
>> My thought is that "-z" should just mean "give me compression; a good
>> default compression setting is fine".  "-Zn" could mean "I want gzip
>> with exactly this compression level" (thus making the presence or
>> absence of -z moot).  If you want to specify some other compression
>> method altogether, use something like --lzma=N.  It seems unlikely to
>> me that somebody who wants to override the default compression method
>> wouldn't want to pick the settings for it too. 

> I think of pg_basebackup as analogous to tar.  tar has a bunch of
> options to set a compression method (-Z, -z, -j, -J), but no support for
> setting compression specific options.  So in that sense that contradicts
> your suspicion.

I would think we'd be more concerned about preserving an analogy to
pg_dump, which most certainly does expose compression-quality options.

			regards, tom lane