No, but disks are about 120 MB/s speed, peak writes during CHECKPOINT are only 20-30 MB/s, and there is no disk read activity at all, so - no matter where the xlog resides.
But now seems bgwriter tuning gets some effect, CHECKPOINT is running faster (about 2-3 seconds instead of 10-15). It is still beats the performance, but less. On 3/29/07, CAJ CAJ <[EMAIL PROTECTED]> wrote:
On 3/28/07, Joseph S <jks@selectacast.net> wrote: > > Dmitry Koterov wrote: > > > And the general question - why SELECT queries slowdown during the > > CHECKPOINT? I thought that Postgres is a version-based database and > read > > queries are never blocked... > > Because the disk is busy. Is your pg_xlog on a separate disk?
