Re: Vacuum and Memory Loss

[Richard Huxton <dev(at)archonet(dot)com>]

Mike wrote:
> Hello friends,
>
> I am responsible for maintaining a high volume website using postgresql
> 8.1.4. Given the amount of reads and writes, I vacuum full the server a
> few times a week around 1, 2 AM shutting down the site for a few
> minutes. The next day morning around 10 - 11 AM the server slows down
> to death. It used to be that the error 'Too many clients' would be
> recorded, until I increased the number of clients it can handle, and
> now it simply slows down to death having lots and lots of postmaster
> processes running:
>
> Tasks: 665 total,  10 running, 655 sleeping,   0 stopped,   0 zombie
> Cpu(s): 14.9% us, 16.7% sy,  0.0% ni,  0.0% id, 68.4% wa,  0.0% hi,
> 0.0% si
> Mem:   2074932k total,  2051572k used,    23360k free,     2736k
> buffers
> Swap:  2096440k total,  1844448k used,   251992k free,   102968k cached

This seems to be saying you have 1.8GB of swap in use. I'd start by 
checking with vmstat whether you're actively swapping. If so, you're 
overallocating memory.

--
  Richard Huxton
  Archonet Ltd