On 16/06/2021 11:17, Andrey Borodin wrote:
16 июня 2021 г., в 12:18, Michael Paquier <mich...@paquier.xyz> написал(а):
Among the
remaining two I would be tempted to choose LZ4. That's consistent
with what toast can use now.
I agree that allowing just lz4 - is already a huge step ahead.
But I'd suggest supporting zstd as well. Currently we only compress 8Kb chunks
and zstd had no runaway to fully unwrap it's potential.
In WAL-G we observed ~3x improvement in network utilisation when switched from
lz4 to zstd in WAL archive compression.
Hmm, do we currently compress each block in a WAL record separately, for
records that contain multiple full-page images? That could make a big
difference e.g. for GiST index build that WAL-logs 32 pages in each
record. If it helps the compression, we should probably start
WAL-logging b-tree index build in larger batches, too.
- Heikki
