Re: Database size growing over time and leads to performance impact - Mailing list pgsql-performance

From Scott Carey
Subject Re: Database size growing over time and leads to performance impact
Date
Msg-id 0E67806D-BED3-4998-83C7-842BEC6447AF@richrelevance.com
Whole thread Raw
In response to Re: Database size growing over time and leads to performance impact  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: Database size growing over time and leads to performance impact  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-performance
On Mar 31, 2010, at 1:47 PM, Robert Haas wrote:

> On Wed, Mar 31, 2010 at 4:37 PM, Scott Carey <scott@richrelevance.com> wrote:
>> On Mar 27, 2010, at 6:35 AM, Andy Colson wrote:
>>>
>>> Dont "VACUUM FULL", its not helping you, and is being removed in newer versions.
>>>
>>
>> Off topic:  How is that going to work?  CLUSTER doesn't work on tables without an index.  I would love to be able to
CLUSTERon some column set that doesn't necessarily have an index. 
>
> I believe the new VF implementation just rewrites the data in the same
> physical order as it was in previously, but without the dead space.
> So it's sort of like cluster-by-no-index-at-all.
>

Still off topic:

Will CLUSTER/VF respect FILLFACTOR in 9.0?

As far as I can tell in 8.4, it does not.  CLUSTER on a table with FILLFACTOR=100, then alter the table to
FILLFACTOR=90,cluster again -- the file size reported by \dt+ is the same.  This is a fairly big performance issue
sinceit means that HOT doesn't function well on a table just CLUSTERed. 

> ...Robert


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