Re: Memory v's CPU

On Wed, 28 May 1997, David Richards wrote:

> So the question remains, "What should we buy?? More memory( 512
> gig ) or bigger processor??? "
>
> All machines will be DEC Alpha's running Digital Unix OSF, there
> is no doubt about that. My impression is that we should go the memory
> option, what do you all reckon?? Is squid more of a memory hungry fellow
> or a processor intensive fellow???
>
> All my tests indicate "memory", am I right??

David,
I'd agree that memory is more of a restriction than CPU. Our University
cache is a DEC Alpha 255-4/232 with 4Gb of disk, which handles about
200000 TCP requests a day. It typically runs at about 90-95% idle CPU, but
ran into serious problems with only 64Mbytes of RAM. Since being upgraded
to 128Mb it, and its users, have been a lot happier. Real memory usage is
around 70Mb though I suspect there's a memory leak in the version of squid
I'm using (1.0.10) as the actual process size is 180M and growing. The
machine is barely swapping at all (about 3000 faults in the past month!),
so I think the leaked pages are just being quietly shuffled off to disk
and ignored.

I appreciate that this is a much smaller cache than you plan, but hope the
comparison with the same machine family is useful.

Andrew

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