On Mon, 2007-05-28 at 08:45 -0400, Dave Cramer wrote: > Since PITR has to enable archiving does this not increase the amount > of disk I/O required ?
As Heikki says, some operations need logging when PITR is on; these are now documented in the performance tips section of the latest dev docs: http://developer.postgresql.org/pgdocs/postgres/populate.html#POPULATE-PITR This isn't additional logging because of PITR, its just that we've had to exclude PITR from some recent tuning operations. I'll be looking at ways of making that optional in certain cases. Overall, the cost of shipping WAL files away has been measured in large scale tests by Mark Wong to be around 1% drop in measured peak transaction throughput, tests about ~2 years ago now on 8.0. It's possible that has increased as we have further tuned the server, but I'm thinking its still fairly negligible overall. Replication solutions currently weigh in significantly more than this overhead, which is one reason to make me start thinking about log based replication in future releases. -- Simon Riggs EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org
