[Info-vax] Apache + mod_php performance

[Arne Vajhøj]

On 9/27/2024 4:13 PM, Dan Cross wrote:
> In article <vd73ho$q3hr$2 at dont-email.me>,
> Arne Vajhøj  <arne at vajhoej.dk> wrote:
>> On 9/27/2024 3:40 PM, Dan Cross wrote:
>>> In article <66f70712$0$711$14726298 at news.sunsite.dk>,
>>> Arne Vajhøj  <arne at vajhoej.dk> wrote:
>>>> On 9/27/2024 3:16 PM, Dan Cross wrote:
>>>>> In article <vd6l5h$pmt5$1 at dont-email.me>,
>>>>> Arne Vajhøj  <arne at vajhoej.dk> wrote:
>>>>>> On 9/26/2024 11:44 AM, Dan Cross wrote:
>>>>>>> In article <vd1u8j$3qqpg$1 at dont-email.me>,
>>>>>>> Arne Vajhøj  <arne at vajhoej.dk> wrote:
>>>>>>>> It must be Apache.
>>>>>>>>
>>>>>>>> Apache on VMS is prefork MPM. Yuck.
>>>>>>>>
>>>>>>>> MaxSpareServers 10 -> 50
>>>>>>>> MaxClients 150 -> 300
>>>>>>>>
>>>>>>>> actually did improve performance - double from 11 to 22
>>>>>>>> req/sec.
>>>>>>>>
>>>>>>>> But the system did not like further increases. And besides
>>>>>>>> these numbers are absurd high to handle a simulator doing requests
>>>>>>>> from just 20 threads.
>>>>>>>>
>>>>>>>> But not sure what else I can change.
>>>>>>>
>>>>>>> My guess is that communications overhead is slowing things down.
>>>>>>> What happens if you set these super low, ideally so there's a
>>>>>>> single process handling requests, then see what sort of QPS
>>>>>>> numbers you get for your trivial text file.
>>>>>>
>>>>>> I set it down to 1.
>>>>>>
>>>>>> 0.1 req/sec
>>>>>
>>>>> So a single request takes 10 seconds?  Or you can only make one
>>>>> request every 10 seconds, but the time taken to process that
>>>>> request is relatively small?
>>>>
>>>> It is throughput.
>>>>
>>>> N / time it takes to get response for N requests
>>>>
>>>> With 20 threads in client then there will always be 20 outstanding
>>>> requests.
>>>
>>> How long does it take to serve a single request?
>>
>> Based on the above information it should be 200 seconds.
>>
>> But it is actually more like 340 seconds. So apparently the 0.1
>> req/sec is rounded up a bit.
> 
> Ok, just to clarify, you hit the web server with a single
> request for a small static resource, while no other traffic was
> hitting it, and that request took more than _five minutes_ to
> complete?

340 seconds is with 20 client threads.

With 1 client thread time is 17 seconds.

As expected.

Arne