softupdate and squid-cache ?

[David Landgren]

User Frankb wrote:

> Hi
> 
> I'm setting up a Squid cache running on latest 4.8 release
> and I wondering about disk write performances as it is
> a crucial point on that kind on machine.
> 
> My question : does softupdate slow down disk writes ? 

What you *really* want to do is put the disk cache on a second disk. 
It's the only game in town for Squid. I mounted a disk as /cache and 
told squid to use that for its cache, keeping its logs under /var on 
the first disk.

I ran tunefs to give the /cache disk the following characteristics 
(based on analysis of my first generation squid server):
tunefs: average file size: (-f)                            8192
tunefs: average number of files in a directory: (-s)       256

Be aware though that by default squid will write so many small files 
that you'll run out of i-nodes before you run out of disk-space. I 
have to reformat the disk this summer when things are quieter, and I 
can get away with a smaller disk cache on the system disk.

At the moment, with the above tunefs settings, I'm using around 3-4% 
more available i-nodes than file blocks used as per df -i output. I'm 
not sure how that translates to specifying the number of i-nodes when 
I reformat the disk.

Hope this helps,
David