Re: [ADMIN] Tests with switch of WAL segment files.

2009-07-17 Thread Kevin Grittner
"J. Carlos Muro" wrote: >> Hi! I am trying to better understand when switch of WAL files takes >> place. I believe that it happens when the file is full, when pg_xlog_switch is run (if there has been anything written to the current WAL file). I think, at least in some version, a switch is als

Re: [ADMIN] Tests with switch of WAL segment files.

2009-07-17 Thread J. Carlos Muro
I realized something else, that only happened once. I recreated the cluster. If I execute "select pg_switch_xlog();" once, then segment file gets almost immediately switched (a new file is created) even though I don't insert new data. If I waite some thime and execute "select pg_switch_xlog();" the

[ADMIN] Tests with switch of WAL segment files.

2009-07-16 Thread J. Carlos Muro
Hi! I am trying to better understand when switch of WAL files takes place. I have executed the next tests while "archive_mode = off": $ initdb -D /var/lib/postgresql/8.3/data $ du -sk /var/lib/postgresql/8.3/data/base 13156 base $ psql -c "drop table if exists heavytable; creat