Re: [squid-users] Performance tuning Squid box for ISP traffic

> Milind Nanal wrote:
> >2) Any fine tune parameters for better performance rather than using
> >default
> >values in squid.conf ?

On 09.12 14:14, Martin Marji Cermak wrote:
> - diskd instead of ufs

aufs on linux should be more effective

> - cache_mem 200 MB if you have enough of RAM
> - maximum_object_size 200 MB (my config, because I want to save traffic)

I posted this already but should do it again: with 3x36 GB cache (3
machines, siblings) I've noticed high decrease of data efficiency after
increasing maximum_object_size from 20 to 32 MB, using LFUDA.

The size 20MB was counted by checking cache logs for the biggest file size
that was repeatedly fetched. Now I added 3x18GB disks, so the efficiency
is increasing again. However I would not use maximum_object_size higher
unless having really much of disk space and customers with the same
interests.

You may notice different numbers, of course.

> - storage size max 85% of available disk space
> and reply_body_max_size 900000000 allow all (or so, to be a bit
> protected agains no content-lenght attack)

IIUC, your customers won't be able to download files bigger than 858MB.
if you want to be protected from such attacks (shouldn't be an issue
imho), I'd recommend you better use 2147483647 ;)

> >3)would like to explore more on different cache replacement policies LUR,
> >GDSF, LFUDA which one is suitable of an ISP class SQUID box ?

> I am running LFUDA at the moment, because I need to save some traffic.
> When I have enough stats, I am going to use GDSF and maybe LUR to
> compare the results. According the info I have found, LFUDA should be
> the best for traffic saving.

some time ago I was comparing LFUDA with GSDF, I noticed that LFUDA had ~2%
higher data efficiency and ~2% lower hit efficiency :)

> And one more remark. People in this list keep saing the reiserfs is the
> best. I decided to use ext3, anyway.
> According to the performance benchmark in the Duane Wessels book "Squid
> the definitive guide", ufs with reiserfs(notail, noatime) has only 61%
> Throughput of ufs with ext3fs(event without notaime option).
> Does anyone have a comment to this?

I'd like to see it. I believe that reisersfs and xfs have benefits for
filesystems like squid cache, that means high number of small files.

> The ext3fs is also handy because you can mount it as ext2fs when you
> need better disk performance and you believe that your box is stable
> enough :-)

if a few minuted of fscking crashed FS is not a problem...

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