regular logging of checkpoint progress

Started by Andy Colsonover 14 years ago6 messages
#1Andy Colson
andy@squeakycode.net

Tomas, I cannot seem to see any of the patches you link here:

https://commitfest.postgresql.org/action/patch_view?id=628

Looks like you need to take the < > out of the messageid.

-Andy

#2Andy Colson
andy@squeakycode.net
In reply to: Andy Colson (#1)
Re: regular logging of checkpoint progress

On 09/05/2011 12:17 PM, Andy Colson wrote:

Tomas, I cannot seem to see any of the patches you link here:

https://commitfest.postgresql.org/action/patch_view?id=628

Looks like you need to take the < > out of the messageid.

-Andy

This patch seems to solve the problem of going back in time to solve a problem. (need time stamped log files to see if things where slow because of checkpoint).

Several people thought a view or some-non-log option would be better. Tomas replied "but I need to go back in time to post diagnose a problem", and I saw no replies to that.

Taking into account Noah's and Greg's "Displaying accumulated autovacuum cost" patch is also sending to logs, do we all now agree that this is proper way?

-Andy

#3Tomas Vondra
tv@fuzzy.cz
In reply to: Andy Colson (#1)
Re: regular logging of checkpoint progress

On 5 Září 2011, 19:17, Andy Colson wrote:

Tomas, I cannot seem to see any of the patches you link here:

https://commitfest.postgresql.org/action/patch_view?id=628

Looks like you need to take the < > out of the messageid.

Sorry, fixed.

Tomas

#4Robert Haas
robertmhaas@gmail.com
In reply to: Andy Colson (#2)
Re: regular logging of checkpoint progress

On Mon, Sep 5, 2011 at 2:02 PM, Andy Colson <andy@squeakycode.net> wrote:

Taking into account Noah's and Greg's "Displaying accumulated autovacuum
cost" patch is also sending to logs, do we all now agree that this is proper
way?

My general impression of the thread is that nobody really wants to
reject the patch (because we all know that we need a lot more logging
options than we currently have) but at the same time nobody seems
quite certain why someone would want to look at this precise bit of
information.

I mean, it's already possible to get log messages at the start and end
of a checkpoint, so there's no problem with finding out whether a
checkpoint was in progress at the time something was slow. In fact,
you can even figure out which phase of the checkpoint you were in.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

#5Simon Riggs
simon@2ndQuadrant.com
In reply to: Robert Haas (#4)
Re: regular logging of checkpoint progress

On Tue, Sep 6, 2011 at 3:48 AM, Robert Haas <robertmhaas@gmail.com> wrote:

On Mon, Sep 5, 2011 at 2:02 PM, Andy Colson <andy@squeakycode.net> wrote:

Taking into account Noah's and Greg's "Displaying accumulated autovacuum
cost" patch is also sending to logs, do we all now agree that this is proper
way?

My general impression of the thread is that nobody really wants to
reject the patch (because we all know that we need a lot more logging
options than we currently have) but at the same time nobody seems
quite certain why someone would want to look at this precise bit of
information.

I mean, it's already possible to get log messages at the start and end
of a checkpoint, so there's no problem with finding out whether a
checkpoint was in progress at the time something was slow.  In fact,
you can even figure out which phase of the checkpoint you were in.

Yes, we need to differentiate between real time and historic
information requirements.

If the requirement is a historical viewpoint then we already have that.

--
 Simon Riggs                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services

#6Fujii Masao
masao.fujii@gmail.com
In reply to: Andy Colson (#2)
Re: regular logging of checkpoint progress

On Tue, Sep 6, 2011 at 3:02 AM, Andy Colson <andy@squeakycode.net> wrote:

Several people thought a view or some-non-log option would be better.

+1

 Tomas
replied "but I need to go back in time to post diagnose a problem", and I
saw no replies to that.

You can go back in time if you periodically collect the information from a view
or some-non-log. Some tools (e.g., pg_statsinfo, Oracle statspack) have already
been doing that.

Regards,

--
Fujii Masao
NIPPON TELEGRAPH AND TELEPHONE CORPORATION
NTT Open Source Software Center