On Wed, Apr 11, 2012 at 10:06 AM, 乔志强 <qiaozhiqiang@xxxxxxxxxxxxxxxx> wrote: > synchronous_commit is not set, default is "on" ? > #synchronous_commit = on # synchronization level; on, off, or local Yes. >>Otherwise the master might be filled up with lots of unsent WAL files and which might cause PANIC error in the master, when there is no standby. >>IOW, the master tries to avoid a PANIC error rather than termination of replication. > > Can we have a config option for keep unsent WAL file for replication ? No. We discussed about such feature before, but it had failed to be committed. I think it's useful, so I hope it'll be usable in the future release. > How can I do when I need a backup standby server and > wal_keep_segments = 3 for save master disk usage(master will delete wal before send to standby now when heavy load, Need modify some config?) Yes, increase wal_keep_segments. Even if you set wal_keep_segments to 64, the amount of disk space for WAL files is only 1GB, so there is no need to worry so much, I think. No? > #checkpoint_segments = 3 # in logfile segments, min 1, 16MB each Increase checkpoint_segments. In this setting, I guess checkpoints run too frequently in heavy load, and WAL files are removed too aggressively. Regards, -- Fujii Masao -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
