> WAL is Write Ahead Log, transaction logging.
> This will reduce # of fsyncs (among other things) Postgres has
> to perform now.
> Test above took near 38 min without -F flag and 24 min
> with -F (no fsync at all).
> With WAL the same test without -F will be near as fast as with
> -F now.
This sounds impressive. So I did some testings with my pgbench to see
how WAL improves the performance without -F using current.
100000 records insertation + vacuum took 1:02 with -F (4:10 without -F)
TPC-B like transactions(mix of insert/update/select) per second:
21 (with -F)
3 (without -F)
I couldn't see any improvement against 6.5.2 so far. Maybe some part
of WAL is not yet committed to current?
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Tatsuo Ishii