Re: Apache + mod_php performance

In article <vd1u8j$3qqpg$1@dont-email.me>,
Arne Vajhøj  <arne@vajhoej.dk> wrote:

On 9/25/2024 2:41 PM, Dan Cross wrote:

In article <vd1bdp$3npm3$1@dont-email.me>,
Arne Vajhøj  <arne@vajhoej.dk> wrote:

On 9/25/2024 8:48 AM, Dan Cross wrote:

Perhaps a simpler question: what sort of throughput does Apache
on VMS give you if you just hit a simple static resource
repeatedly?

>
Now it becomes interesting.
>
nop.php also gives 11 req/sec.
>
And nop.txt also gives 11 req/sec.
>
So the arrow is definitely pointing towards Apache.

 
I should think so.  Lesson #1: always verify your base
assumptions when investigating something like this.
 

So either something to speed up Apache or switching to WASD or OSU.

 
Well, the question now becomes, "what makes Apache so slow?"
 
I would concentrate on your nop.txt test; I assume that's a
small (possibly empty) text file and as an example has the
fewest number of variables.
 
Do your logs give any indications of what might be going on?
For example, do the logs have host names in them, possibly
implying your stalling on reverse DNS lookups or something
similar?

>
Just logging IP address.
>
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.

- Dan C.