Re: Teach pg_receivewal to use lz4 compression

On Thu, Jul 1, 2021 at 3:39 PM <gkokolatos@pm.me> wrote:
>
>
>
> ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
>
> On Thursday, July 1st, 2021 at 12:28, Magnus Hagander <magnus@hagander.net> wrote:
>
> > On Wed, Jun 30, 2021 at 8:34 AM Dilip Kumar dilipbalaut@gmail.com wrote:
> >
> > > On Tue, Jun 29, 2021 at 8:15 PM gkokolatos@pm.me wrote:
> > >
> > > > Hi,
> > > >
> > > > The program pg_receivewal can use gzip compression to store the received WAL.
> > > >
> > > > This patch teaches it to be able to use lz4 compression if the binary is build
> > > >
> > > > using the -llz4 flag.
> > >
> > > +1 for the idea
> > >
> > > Some comments/suggestions on the patch
> > >
> > > @@ -90,7 +91,8 @@ usage(void)
> > >
> > > printf((" --synchronous flush write-ahead log immediately
> > >
> > > after writing\n"));
> > >
> > > printf((" -v, --verbose output verbose messages\n"));
> > >
> > > printf(_(" -V, --version output version information, then exit\n"));
> > >
> > > -   printf(_(" -Z, --compress=0-9 compress logs with given
> > >
> > >     compression level\n"));
> > >
> > > -   printf(_(" -I, --compress-program use this program for compression\n"));
> > >
> > > Wouldn't it be better to call it compression method instead of
> > >
> > > compression program?
> >
> > I came here to say exactly that, just had to think up what I thought
> >
> > was the better name first. Either method or algorithm, but method
> >
> > seems like the much simpler choice and therefore better in this case.
> >
> > Should is also then not be --compression-method, rather than --compress-method?
>
> Not a problem. To be very transparent, I first looked what was already out there.
> For example `tar` is using
>     -I, --use-compress-program=PROG
> yet the 'use-' bit would push the alignment of the --help output, so I removed it.

I think the difference there is that tar actually calls an external
program to do the work... And we are using the built-in library,
right?

--
 Magnus Hagander
 Me: https://www.hagander.net/
 Work: https://www.redpill-linpro.com/