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....
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 ?
And what kind of h/w specification you suggest for such kind of load ?
Kindly suggest us.
With content filtering you can usually expect only to reach 30% of
Squids regular throughput due to the content processing overheads.
250 users is not large for Squid. Any of the production releases
should be able to handle that many without causing much of a CPU bump
on modern hardware. I think you can start with one Squid process and
expand to more if you find it stressing the machines. More likely you
will need more DansGuardian proxy processes though, that is where the
heavy CPU consumption will occur.
Amos
Regards,
Ben
