On 2017-04-28 01:29:14 +0200, Tomas Vondra wrote: > I can confirm this observation. I bought the Intel 750 NVMe SSD last year, > the device has 1GB DDR3 cache on it (power-loss protected), can do ~1GB/s of > sustained O_DIRECT sequential writes. But when running pgbench, I can't push > more than ~300MB/s of WAL to it, no matter what I do because of > WALWriteLock. Hm, interesting. Even if you up wal_buffers to 128MB, use synchronous_commit = off, and play with wal_writer_delay/flush_after? - Andres -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance