Re: WAL_DEBUG - Mailing list pgsql-general

From Jeff Janes
Subject Re: WAL_DEBUG
Date
Msg-id CAMkU=1y-0d06y3sxeUPjML+pXOQGYXBHOToMHj6auP3uVviQOg@mail.gmail.com
Whole thread Raw
In response to WAL_DEBUG  (ning chan <ninchan8328@gmail.com>)
Responses Re: WAL_DEBUG
List pgsql-general
On Wed, Mar 6, 2013 at 1:31 PM, ning chan <ninchan8328@gmail.com> wrote:
Hi,
Does anyone know how to enable WAL_DEBUG?
I download postgresql 9.2.3 src code and compile it as follow:


modify ./src/include/pg_config_manual.h
/*
 * Enable debugging print statements for WAL-related operations; see
 * also the wal_debug GUC var.
 */
#define WAL_DEBUG 4


 ./configure --without-readline --without-zlib CPPFLAGS='-DWAL_DEBUG'

Either one of those works for me.
 

I don't see anything special log to the log file.

open running pgbench -i, I see a lot of things like this in the log, once I set wal_debug:

STATEMENT:  alter table pgbench_accounts add primary key (aid)
LOG:  INSERT @ 0/18BEDC0: prev 0/18BED78; xid 1838; len 34: Btree - insert: rel 1663/16384/12678; tid 1/8
STATEMENT:  alter table pgbench_accounts add primary key (aid)
LOG:  INSERT @ 0/18BEE08: prev 0/18BEDC0; xid 1838; len 52: Heap - insert: rel 1663/16384/12765; tid 46/29
STATEMENT:  alter table pgbench_accounts add primary key (aid)
LOG:  INSERT @ 0/18BEE60: prev 0/18BEE08; xid 1838; len 42: Btree - insert: rel 1663/16384/12767; tid 27/140
STATEMENT:  alter table pgbench_accounts add primary key (aid)
LOG:  INSERT @ 0/18BEEB0: prev 0/18BEE60; xid 1838; len 42: Btree - insert: rel 1663/16384/12768; tid 26/14



I even try to add a line wal_debug=number to the postgresql.conf, doesn't help either.


If I include literally "wal_debug=number", upon start up I get the self-explanatory error:

LOG:  parameter "wal_debug" requires a Boolean value
FATAL:  configuration file "/tmp/data/postgresql.conf" contains errors

If I replace "number" with a valid true value ("true", "on", "1"), then I get the above-reported WAL debugging log messages.

Cheers,

Jeff

pgsql-general by date:

Previous
From: ning chan
Date:
Subject: WAL_DEBUG
Next
From: Dean Rasheed
Date:
Subject: Re: Why does slony use a cursor? Anyone know?