Re: TODO item: adding VERBOSE option to CLUSTER [with patch] - Mailing list pgsql-hackers

From Heikki Linnakangas
Subject Re: TODO item: adding VERBOSE option to CLUSTER [with patch]
Date
Msg-id 48F32F62.5040205@enterprisedb.com
Whole thread Raw
In response to Re: TODO item: adding VERBOSE option to CLUSTER [with patch]  ("Jim Cox" <shakahshakah@gmail.com>)
Responses Re: TODO item: adding VERBOSE option to CLUSTER [with patch]
List pgsql-hackers
Jim Cox wrote:
> On Fri, Oct 10, 2008 at 10:23 AM, Heikki Linnakangas <
> heikki.linnakangas@enterprisedb.com> wrote:
> 
>> Kevin Grittner wrote:
>>
>>> "Jim Cox" <shakahshakah@gmail.com> wrote:
>>>>> if present an INFO message is generated which displays
>>>> the schema.tblname just before actual clustering is kicked off (see
>>>>
>>> example
>>>
>>>> below).
>>>>
>>>
>>>> postgres=# CLUSTER VERBOSE ;
>>>> INFO:  clustering "public.my_b"
>>>> INFO:  clustering "public.my_c"
>>>> INFO:  clustering "public.my_a"
>>>> CLUSTER
>>>>
>>>  Would it make sense to display the pg_total_relation_size before and
>>> after?
>>>
>> Assuming you run CLUSTER as a replacement for VACUUM FULL, yes. More
>> interesting would be a metric of "clusteredness", I think.
>>
> 
> Something more like the following?
> 
> postgres=# CLUSTER VERBOSE ;
> INFO:  clustering "public.my_b"
> INFO:  complete, 0 rows scanned, 0 rows now live
> DETAIL:  CPU 0.00s/0.00u sec elapsed 0.00 sec.
> INFO:  clustering "public.my_c"
> INFO:  complete, 20 rows scanned, 10 rows now live
> DETAIL:  CPU 0.00s/0.00u sec elapsed 0.00 sec.
> INFO:  clustering "public.my_a"
> INFO:  complete, 10 rows scanned, 10 rows now live
> DETAIL:  CPU 0.00s/0.00u sec elapsed 0.00 sec.
> CLUSTER

No, I was thinking of something along the lines of:
INFO:  clustering "public.my_c"
INFO:  complete, was 33%, now 100% clustered

The only such measure that we have is the correlation, which isn't very 
good anyway, so I'm not sure if that's worthwhile.

--   Heikki Linnakangas  EnterpriseDB   http://www.enterprisedb.com


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