Re: [HACKERS] Why copy_relation_data only use wal when WALarchiving is enabled

2007-10-18 Thread Jacky Leng
You need to set $PGDATA before running the script. And psql,pg_ctl and pg_resetxlog need to be in $PATH. After running the script, restart postmaster and run SELECT * FROM t2. There should be one row in the table, but it's empty. I've tried this script, and superisingly found that T2 is not

Re: [HACKERS] Why copy_relation_data only use wal when WALarchiving is enabled

2007-10-18 Thread Jacky Leng
Sorry, send the mail wrongly just now. You need to set $PGDATA before running the script. And psql,pg_ctl and pg_resetxlog need to be in $PATH. After running the script, restart postmaster and run SELECT * FROM t2. There should be one row in the table, but it's empty. I've tried this script

Re: [HACKERS] Why copy_relation_data only use wal when WALarchiving is enabled

2007-10-18 Thread Jacky Leng
You need to set $PGDATA before running the script. And psql,pg_ctl and pg_resetxlog need to be in $PATH. After running the script, restart postmaster and run SELECT * FROM t2. There should be one row in the table, but it's empty. I've tried this script on postgres (PostgreSQL) 8.3devel, and

Re: [HACKERS] Why copy_relation_data only use wal when WALarchiving is enabled

2007-10-18 Thread Jacky Leng
You need to set $PGDATA before running the script. And psql,pg_ctl and pg_resetxlog need to be in $PATH. After running the script, restart postmaster and run SELECT * FROM t2. There should be one row in the table, but it's empty. I've tried this script on postgres (PostgreSQL) 8.3devel, and

Re: [HACKERS] Why copy_relation_data only use wal when WALarchiving is enabled

2007-10-17 Thread Heikki Linnakangas
Simon Riggs wrote: On Wed, 2007-10-17 at 17:18 +0800, Jacky Leng wrote: Second, suppose that no checkpoint has occured during the upper series--authough not quite possible; That part is irrelevant. It's forced out to disk and doesn't need recovery, with or without the checkpoint.

Re: [HACKERS] Why copy_relation_data only use wal when WALarchiving is enabled

2007-10-17 Thread Jacky Leng
On Wed, 2007-10-17 at 17:18 +0800, Jacky Leng wrote: Second, suppose that no checkpoint has occured during the upper series--authough not quite possible; That part is irrelevant. It's forced out to disk and doesn't need recovery, with or without the checkpoint. There's no hole that I can

Re: [HACKERS] Why copy_relation_data only use wal when WALarchiving is enabled

2007-10-17 Thread Heikki Linnakangas
Forgot to attach the script I promised.. You need to set $PGDATA before running the script. And psql,pg_ctl and pg_resetxlog need to be in $PATH. After running the script, restart postmaster and run SELECT * FROM t2. There should be one row in the table, but it's empty. Heikki Linnakangas wrote:

Re: [HACKERS] Why copy_relation_data only use wal when WALarchiving is enabled

2007-10-17 Thread Heikki Linnakangas
I wrote: Unfortunately I don't see any easy way to fix it. One approach would be to avoid reusing the relfilenodes until next checkpoint, but I don't see any nice place to keep track of OIDs that have been dropped since last checkpoint. Ok, here's one idea: Instead of deleting the file

Re: [HACKERS] Why copy_relation_data only use wal when WALarchiving is enabled

2007-10-17 Thread Florian G. Pflug
Heikki Linnakangas wrote: I wrote: Unfortunately I don't see any easy way to fix it. One approach would be to avoid reusing the relfilenodes until next checkpoint, but I don't see any nice place to keep track of OIDs that have been dropped since last checkpoint. Ok, here's one idea: Instead

Re: [HACKERS] Why copy_relation_data only use wal when WALarchiving is enabled

2007-10-17 Thread Simon Riggs
On Wed, 2007-10-17 at 12:11 +0100, Heikki Linnakangas wrote: Simon Riggs wrote: On Wed, 2007-10-17 at 17:18 +0800, Jacky Leng wrote: Second, suppose that no checkpoint has occured during the upper series--authough not quite possible; That part is irrelevant. It's forced out to disk

Re: [HACKERS] Why copy_relation_data only use wal when WALarchiving is enabled

2007-10-17 Thread Florian G. Pflug
Simon Riggs wrote: On Wed, 2007-10-17 at 12:11 +0100, Heikki Linnakangas wrote: Simon Riggs wrote: On Wed, 2007-10-17 at 17:18 +0800, Jacky Leng wrote: Second, suppose that no checkpoint has occured during the upper series--authough not quite possible; That part is irrelevant. It's forced out

Re: [HACKERS] Why copy_relation_data only use wal when WALarchiving is enabled

2007-10-17 Thread Heikki Linnakangas
Florian G. Pflug wrote: Heikki Linnakangas wrote: I wrote: Unfortunately I don't see any easy way to fix it. One approach would be to avoid reusing the relfilenodes until next checkpoint, but I don't see any nice place to keep track of OIDs that have been dropped since last checkpoint. Ok,