Now, with ext4 moving to full barrier/fsync support, we could get to the point where WAL in the main data FS can mimic the state where WAL is seperate, namely that WAL writes can "jump the queue" and be written without waiting for the data pages to be flushed down to disk, but also that you'll get the big backlog of data pages to flush when the first fsyncs on big data files start coming from checkpoints...
Does postgres write something to the logfile whenever a fsync() takes a suspiciously long amount of time ?
-- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
