Re: Manual vacs 5x faster than autovacs?

On Mon, Nov 16, 2009 at 9:13 AM, Wayne Beaver <wayne(at)acedsl(dot)com> wrote:
>> Quoting Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com>:
>>
>>> On Thu, Nov 12, 2009 at 9:58 AM, Wayne Beaver <wayne(at)acedsl(dot)com> wrote:
>>>>
>>>> Quoting Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com>:
>>>>
>>>>>> On Thu, Nov 12, 2009 at 9:14 AM, Wayne Beaver <wayne(at)acedsl(dot)com>
>>>>>> wrote:
>>>>>> I'd seen autovacs running for hours and had mis-attributed this to
>>>>>> growing query times on those tables  - my thought was that "shrinking"
>>>>>> the tables
>>>>>> "more quickly" could make them "more-optimized", more often. Sounds
>>>>>> like
>>>>>> could be chasing the wrong symptoms, though.
>>>>>
>>>>> Now it is quite possible that a slow autovac is causing your queries
>>>>> to run slower.  So, if it has a moderate to high cost delay, then it
>>>>> might not be able to keep
>>>>> up with the job and your tables will become bloated.
>>>>>
>>>>> The problem isn't that autovac is stealing too many resources, it's
>>>>> that it's not stealing enough.
>>>>>
>>> I've not yet gotten to you iostat inquiry from your previous response...
>>
>> Don't worry too much, just want to see if your IO system is maxed out.
>
>
> $ iostat
> Linux 2.6.18.8-0.9-default (myserver)   11/16/2009
>
> avg-cpu:  %user   %nice %system %iowait  %steal   %idle
>          28.11    3.13    6.50    8.71    0.00   53.56
>
> Device:            tps   Blk_read/s   Blk_wrtn/s   Blk_read   Blk_wrtn
> sda             153.08      7295.23      3675.59 123127895363 62036043656\

That's just since the machine was turned on. run it like:

iostat -x 10

and see what comes out after the first one.