Re: [squid-users] what do i need to get the job done, performance squid

william wrote:
> Amos Jeffries wrote:
>> william wrote:
>>> Chris Robertson wrote:
>>>> william wrote:
>>>>> i would assigh 12GB memcache and four disks with diskd to each
>>>>> instance.
>>>>
>>>>
>>>> Last I heard, diskd was not the recommended cache_dir algorithm
>>>> under Linux. If you are looking for maximum performance, Squid 2.7
>>>> with a combination of COSS and aufs is the current route to take.
>>>> On the other hand, the 3.1 branch of Squid is where the majority of
>>>> development effort is being focused.
>>>>
>>> I thought about diskd for some threading. But if COSS is the way to
>>> go i will set that up.
>>> I also think about squid 3.1 because of the nice features implemented.
>>>
>>
>> 3.1 does not provide COSS and is still a little bit slower than 2.7.
>>
>> Amos
> Amos
>
> how little slower?
> mean 5000 concurrent connections less or maybe a litle bit slower like
> like 200 connections.

_new_ requests per second. Squid can pump data across existing
concurrent connections as fast as the NIC and CPU can copy it. It's the
CPU intensive new request parsing and disk IO which limits Squid.

I have not sen any direct 2.7vs3.1 benchmarks done yet. However Adrian
did some testing on 2.7vs3.0 and I've done some more recent spot checks
on 3.0vs3.1.
Using 3.0 which we both tested as a baseline my maths comes out at 2.7
roughly 150 rps higher.

(3.2 is now beating 2.7 by my math :), but its a year away from production.)

> Or is it in the disk subsystem?
>

Disk IO is not very different between the versions. With the exceptions
of RAM-cache in 3.x being much faster for large MB+ objects. And COSS in
2.7 provides a speed boost over other disk types, being much faster for
the small objects it can hold.

> And what about stability and features like ntlm passthrough auth?

The features which are present in both have usually had some polish to
the configuration for 3.x. Very little in them though.

There are still a few features which are not in 3.x yet. collapsed
forwarding being the most noticed.

>
> i tested this with squid 3.1 which works perfectly.
> But 3.1 latest has no fix for bug 2155 and i get those once in two days.
> I know this is fixed in the tree as stated in the bug report.

3.1.0.16 is due out very soon. Meanwhile the snapshot available on the
3.1 download web page has that and several other important fixes already in.

>
> Any further recommendations for disk / os tuning?
>
> With kind regards
>
> William

Amos

-- 
Please be using
   Current Stable Squid 2.7.STABLE7 or 3.0.STABLE21
   Current Beta Squid 3.1.0.15