Re: Autovacuum in the backend

Andrew Dunstan wrote:

>Gavin Sherry said:
>  
>
>>I think this gets away from my point a little. People with 2 TB tables
>>can take care of themselves, as can people who've taken the time to
>>partition their tables to speed up vacuum. I'm more concerned about the
>>majority of people who fall in the middle -- between the hobbiest and
>>the high end data centre.
>>
>>    
>>
>
>My only problemn with what you say is that we should not incorporate AV into
>the backend until these things have been solved. This would be one step down
>a long raod, and that's how it should be positioned.
>  
>

Right, I think if VACUUM is improved than the semantics of AV in the 
backend might change, but I think there will always be a need for some 
maintenance, and a daemon that monitors the maintenance needs of your 
database and fires off appropriate maintenance commands for you is 
good.  No it doesn't solve all problems, but I think it solves a lot of 
problems for a lot of people.  Besides VACUUM isn't the only the AV 
does, it also does ANALYZE to keep your stats up-to-date and it watches 
for XID wraparound.  It could also look for REINDEX opportunities and 
who knows what else in the future.

>I am very concerned that with Feature Freeze 2 weeks away we seem to be in a
>similar position to where we were a year ago. I know we don't even promise
>anything, but certainly I and others believed that work was being done to
>get AV into the backend in 8.1. Not doing this because we think it could be
>lots better would not give people a good impression of our processes. I
>certainly don't think it will make matters worse, especially if it's not on
>by default.
>  
>

I agree.  Also, some people in this thread have been making noises about 
wanting AV on by default.  This might be nice, but I am still leaning 
towards off by default at least in 8.1.