Re: [squid-users] Problems with squid in a campus setup

>> But read the FAQ about memory usage and a large disk cache:
>> http://wiki.squid-cache.org/SquidFaq/SquidMemory
>> Squid uses an additional 512*14 MB = 7.1 GB for the index of the disk
>> cache. I suggest to downsize to 1 GB in-memory index which implies to
>> use only 73 GB disk cache.
>
> Ah okay, here's one of my initial mistakes. I used only 10 MB for my
> calculation but of course we use a 64bit squid. Out of curiosity and because I
> want to learn: the reasoning for shrinking the disk cache from 512 GB to 73 GB
> is because a big cache as we have it at the moment only leads to lots of stale
> objects in cache which additionally burden the CPU and RAM because of in-
> memory metadata?

The downsize is required to stop exhausting the resources of the server.
The server needs space for OS, file system buffer, TCP buffers, other
processes etc.
Once you downsized, you can add a little more disk cache in small steps
observing the performance over longer periods of time.

You did not publish the whole squid.conf, but for large disk caches
the parameters cache_swap_low and cache_swap_high are important.
They should differ only by 1 point. I recommend
cache_swap_low 93
cache_swap_high 94

Marcus
Received on Tue Mar 27 2012 - 12:32:46 MDT