Re: How do you change the size of the WAL files?

>> >  instalation.  If necessary, I can rebuild the entire cluster.  Our

>> >  DBA initialized a new cluster and specified a larger WAL size but it

>> >  stayed at 16 Mb.  Any info on this?

>> 

>> Why is 16MB too small?  Most people increase checkpoint_segments for

>> larger installs and it works fine.


>To answer the question, it is possible to change the wal log size. It is

>a setting in pg_config.h: #define XLOG_SEG_SIZE (16 * 1024 * 1024) .

>

>If you change that and recompile, your wal segment size will be

>different. I have heard of people running 32meg sizes. We have tried

>with smaller sizes but it ended up thrashes the disk.

>

>Further keep in mind you will have to do a dump and restore to the new

>cluster. Your existing cluster will not be usable once you do this.


Probably won't change then.  The boss was worried that a 16 Mb file size would cause performance issues on a busy database server.