On 2014-12-16 16:12:40 +0200, Heikki Linnakangas wrote: > On 12/15/2014 08:51 PM, Simon Riggs wrote: > >Currently, WALReceiver writes and fsyncs data it receives. Clearly, > >while we are waiting for an fsync we aren't doing any other useful > >work. > > > >Following patch starts WALWriter during recovery and makes it > >responsible for fsyncing data, allowing WALReceiver to progress other > >useful actions. > > What other useful actions can WAL receiver do while it's waiting? It doesn't > do much else than receive WAL, and fsync it to disk.
It can actually receive further data from the network and write it to disk? On a relatively low latency network the buffers aren't that large. Right now we generate quite a bursty IO pattern with the disks alternating between idle and fully busy. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
