Re: four minor proposals for 9.5 - Mailing list pgsql-hackers

From Pavel Stehule
Subject Re: four minor proposals for 9.5
Date
Msg-id CAFj8pRDdvdx5bsknoqXo=5m4nREC6u4uCMgf29dn7259AaE9Sg@mail.gmail.com
Whole thread Raw
In response to Re: four minor proposals for 9.5  (Amit Kapila <amit.kapila16@gmail.com>)
List pgsql-hackers



2014-04-10 5:50 GMT+02:00 Amit Kapila <amit.kapila16@gmail.com>:
On Tue, Apr 8, 2014 at 9:07 PM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
> 2014-04-08 6:27 GMT+02:00 Amit Kapila <amit.kapila16@gmail.com>:
>> So do you want to just print lock time for error'd statements, won't
>> it better to
>> do it for non-error'd statements as well or rather I feel it can be more
>> useful
>> for non-error statements? Do we already have some easy way to get
>> wait-time
>> for non-error statements?
>
>
> There are two points:
>
> a) we have no a some infrastructure how to glue some specific info to any
> query other than log_line_prefix.

Can't we do that by using log_duration and log_min_duration_statement?
For Example, if I enable these parameters, below is the log:

LOG:  duration: 343.000 ms  statement: create table t1(c1 int);

yes, sorry. You have true. I though about this possibility, and I choose log_line_prefix due simple configurability and better parserability. But again, enhancing log_duration feature can be implement together with enhancing log_line_prefix.

I'll try to visualise in prototype.

Regards

Pavel
 

> And I have no any idea, how and what
> implement better. And I don't think so any new infrastructure (mechanism) is
> necessary. log_line_prefix increase log size, but it is very well parseable
> - splunk and similar sw has no problem with it.

One thing that could happen if we implement total lock time at
log_line_prefix is that if user enables log_lock_waits, then it will start
printing duration for each lock wait time, not sure again it depends on
implementation.

> b) lock time can be interesting on error statements too - for example - you
> can cancel locked queries - so you would to see a lock time and duration for
> cancelled queries. So this implementation can be sensible too.

Agreed, I just said it will be quite useful for non-error'd long running
statements as well, so it might be good idea to see if we can implement
it for successful statements as well.


With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com

pgsql-hackers by date:

Previous
From: Pavan Deolasee
Date:
Subject: Re: Autonomous Transaction (WIP)
Next
From: David Rowley
Date:
Subject: Re: [PATCH] Negative Transition Aggregate Functions (WIP)