Re: Autovacuum in the backend

Bruce Momjian wrote:

>Hannu Krosing wrote:
>  
>
>>On K, 2005-06-15 at 13:41 +0800, Qingqing Zhou wrote:
>>    
>>
>>>"Neil Conway" <neilc@samurai.com> writes
>>>      
>>>
>>>>Wasn't the plan to rewrite pg_autovacuum to use the FSM rather than the
>>>>stats collector?
>>>>        
>>>>
>Yes, those are step five.  The TODO list has:
>    
>    * Auto-vacuum
>            o Move into the backend code
>            o Scan the buffer cache to find free space or use background writer
>            o Use free-space map information to guide refilling
>            o Do VACUUM FULL if table is nearly empty?
>


I think the two can be used in conjunction with one another, and perhaps 
one day it could be used with or without the stats system.  Integrating 
FSM information has to be helpful, but it also isn't going to tell us 
when to do an analyze due to lots of inserts, also the FSM (if not big 
enough) is lossy and might not be tracking all the tables.  So I think 
for 8.1 if it only used stats that would be OK.