Re: [squid-users] Squid Processes

> On 26/02/2012 6:59 a.m., Ben wrote:
>> Hi Amos,
>>> On 22.02.2012 03:15, Steve Tatlow wrote:
>>>> Hi,
>>>>
>>>> We are running squid as a transparent proxy, with dansguardian
>>>> doing the
>>>> content filtering. All traffic will be coming from localhost and no
>>>> authentication is required. Can someone tell me how I ensure there
>>>> are
>>>> enough squid processes to support a large number of users (maybe 250
>>>> concurrent users)
>>>
>>> None of us can tell you specific numbers. It is dependent on your
>>> hardware and client traffic.
>>>
>>> The thing to be aware of is that measuring in users is meaningless.
>>> One user can flood the proxy, or some thousands could leave it idle
>>> waiting for more work. Capacities are reliably measured only in
>>> requests per second.
>>>
>>>
>>> To get the details you seek measure and get some idea of how many
>>> requests per second those users make at peak times, and how many the
>>> whole structure is capable of handling.
>>> Each Squid series has a theoretical limit which is hardware
>>> dependant (3.1 can do about 800 req/sec on a dual core 2.2GHz CPU
>>> etc). The configuration specifics you create and type of requests
>>> the clients will reduce the capacity limit from there.
>>>
>> You mean to say that single squid instance can handle 800 req/sec on
>> a dual core 2.2 GHz CPU ? Can you elaborate it in details means how
>> many hdd have you used and is there any specific configuration do you
>> want to highlight....
>
> We have a test machine which can reach that. Nothing special on the
> hardware, and in active use running several other services. But the
> test is a bit artificial. So I think overall its a reasonable sort of
> result. Your mileage *will* vary.
>
>>
>> As i tested single squid instance with 400-450 req / sec and it is
>> performing fine.Currently i deployed squid with 175 Mbps bandwidth
>> load.Now we plan to use it for 400 Mbps so it suppose be 800 or 900
>> http req / sec , Does single squid process handle such heavy load or ?
>
> The fact you got past 50Mbps easily at ~400 req/sec tells me your
> traffiic might be a bit unusual. On the ISP scenario I'm used to
> estimating with most of the reports have needed two Squid to get over
> 100Mbps. Good news for you, bad news for forcasting the limits.
>
You mean two instances of squid on same h/w to handle 100 Mbps.? As in
production i m using squid with 175 Mbps bandwidth usage and 450 http
req / sec.
And it seems fine.Yes sometimes my cpu consumption is ~ 95 % and memory
is 85 % but generally cpu consumption is ~40 % and memory is ~ 70 %.

As now i tested with single disk( 10k rpm). But now i plan to upgrade it
with more hdd.

>>
>> And what kind of h/w specification you suggest for such kind of load ?
>
> At this point you have a Squid already to use as baseline. So you can
> look at the resource usage CPU, memory, Disk I/O etc and guess (yes
> guess) how much more load it can take before any one of those is maxed
> out.
>
> Amos
Ben
Received on Sun Feb 26 2012 - 11:18:08 MST