Re: Add LZ4 compression in pg_dump

On Sun, Mar 27, 2022 at 12:37:27AM +0100, Daniel Gustafsson wrote:
> > On 26 Mar 2022, at 17:21, Justin Pryzby <pryzby(at)telsasoft(dot)com> wrote:
>
> > I suggested off-list to add an 0099 patch to change LZ4 to the default, to
> > exercise it more on CI.
>
> No need to change the defaults in autoconf for that. The CFBot uses the cirrus
> file in the tree so changing what the job includes can be easily done (assuming
> the CFBot hasn't changed this recently which I think it hasn't). I used that
> trick in the NSS patchset to add a completely new job for --with-ssl=nss beside
> the --with-ssl=openssl job.

I think you misunderstood - I'm suggesting not only to use with-lz4 (which was
always true since 93d973494), but to change pg_dump -Fc and -Fd to use LZ4 by
default (the same as I suggested for toast_compression, wal_compression, and
again in last year's patch to add zstd compression to pg_dump, for which
postgres was not ready).

@@ -781,6 +807,11 @@ main(int argc, char **argv)
compress.alg = COMPR_ALG_LIBZ;
compress.level = Z_DEFAULT_COMPRESSION;
#endif
+
+#ifdef USE_ZSTD
+ compress.alg = COMPR_ALG_ZSTD; // Set default for testing purposes
+ compress.level = ZSTD_CLEVEL_DEFAULT;
+#endif