Re: Performance tuning

OK.. How about this one:
I have two caches, with the following two specs,
each with 100Mbps connection to Net.

1. 512MB RAM, 9GB disk.
2. 256MB RAM, 9GB disk.
These are dedicated machines.

- What should I set cache_mem to? How does one
decide on this value?
- the number of SwapDirs?,
- number of L1 and L2 directories for on-disk cache?
- the low-water and high-water marks for both the
cache-mem and the on-disk cache?
- the average size of a cached object (used by Squid to
size the SwapDir's FileMap)?

thanks,
chris stein

On Sat, 20 Nov 1999, Henrik Nordstrom wrote:

> Jason Thompson wrote:
>
> > 1. What is a recommended cache size to gain best performance? is
> > there a size where you stop getting any performance gain or is it
> > simply the bigger the better?
>
> It all depends on your funds. Larger caches requires more disk and
> memory, and percieved speed very much depends in connection bandwidth.
>
> > 2. How much physical memory should the cache have in the machine,
> > and how much should squid have allocated in the squid.conf file?
>
> In your setup cache_mem should probably be 2 MB.
>
> Also, remember to limit (or even disable) memory pools.
> memory_pools_limit 1 MB
> or
> memory_pools off
>
> > 3. I want to get the cache running as fast as possible for the
> > following system below:
> > ISDN Link to the net at 64Kbs
> > Approx 100 Clients
> > Server Currently: P166, 32MB RAM, 2GB HD
> > OS: Redhat 6.0
>
> With only 64Kbps link it is hard to configure a cache to not be able to
> handle it.
>
> > Could anyone offer me some tips for tuning the cache. It would
> > be best if the cache made as little access to the Internet as
> > possible. i.e not bother checking expire dates for cache objects. As
> > long as users can manually refresh the pages using the web browser.
>
> Problem is that is hard to distinguish between public and private
> content when you begin to bend expiry rules. Some servers return private
> content with no indication that it is private except that the page
> contains no expiry information.
>
> If you want to experiment with this, see refresh_pattern and
> offline_mode settings, but be prepared to see problems with private
> content like web based email access.
>
> --
> Henrik Nordstrom
> Squid hacker
>
>
Received on Sat Nov 20 1999 - 19:42:22 MST