Kernel how-to

[CGS|Todd]

BrutalGoerge Wrote:no matter what it seems, i do a new kernel, get 1000 fps, but loading times on the server are increased by a factor of 10.

I duno why I keep bothering. I never see a difference between 300FPS vs 1000. I don't think anyone else really does either. When people know their server is doing 1000 fps, their mind is tricked into thinking it's running better, much like a sugar pill.

if loading is slow you may be missing the native disk controller module.

but yes, 1000fps is mostly a sugar pill in my opinion. surely some 1000fps whore will post a flame about this comment, but in the end, 99% of people don't notice and/or care. if you are part of the 1%, more power to you, but its not what the masses need or want.

bottom line -- is it better, probably to some tiny degree . . . is it necessary, no.

[BehaartesEtwas]

try playing around with the different clock sources:
cat /sys/devices/system/clocksource/clocksource0/available_clocksource
will give you the clock sources your kernel supports. then write one of them into current_clocksource, e.g.:
echo tsc > /sys/devices/system/clocksource/clocksource0/current_clocksource
this *might* change your fps a *very* little bit.

But: I never optimized my systems for as high as possible fps, because this does not make sense. Much more important is the stability, as even the smaller fps deviations are notable affecting the game play. I have made diverse blind tests which confirms this (on the source engine) ;-)

Also, I cannot guarantee that there is no better kernel than the one described in the howto, of course. If you have found something better, feel free to create your own howto in my wiki!

[bleomycin]

Is there any risk in removing QoS and/or fair queueing from networking? Will there be no ill effect if a 100megabit line is being saturated and this is disabled? I'm clearly clueless about exactly how it functions. Thanks.

[janne]

Just for fun i tried kernel 2.6.24.7-rt24, but max fps i get is ~495...
I used basically the same .config I had in my 2.6.26.6-rt11 which give me ~970fps
(Both are configured according to the original posters wiki.)

Any ideas?

[BehaartesEtwas]

Quote:Is there any risk in removing QoS and/or fair queueing from networking? Will there be no ill effect if a 100megabit line is being saturated and this is disabled? I'm clearly clueless about exactly how it functions. Thanks.

QoS is only needed, if you want to priorize network traffic. Unless you are using some software to configure it, it will be just adding some additional (but very small) overhead in the network code of the kernel. I.e.: If you did not explicitly used QoS before, you can just disable it in kernel without any side effects.

Quote:Just for fun i tried kernel 2.6.24.7-rt24, but max fps i get is ~495...
I used basically the same .config I had in my 2.6.26.6-rt11 which give me ~970fps
(Both are configured according to the original posters wiki.)

That's strange, because I am still using that kernel on my productive root, and get good results (at least before I switched to my new secret system ^^). Maybe you got one of the settings wrong? Or maybe, fps_max is not 0?

[janne]

BehaartesEtwas Wrote:That's strange, because I am still using that kernel on my productive root, and get good results (at least before I switched to my new secret system ^^). Maybe you got one of the settings wrong? Or maybe, fps_max is not 0?

Yes, I'm sure

Code:

fps_max
"fps_max" = "0" ( def. "300" )
- Frame rate limiter
stats
CPU   In    Out   Uptime  Users   FPS    Players
14.50 5287.75 9779.70       6     0  487.33       4

Only thing that differs in kernel from the wiki is
"Network packet filtering framework" because of the firewall.

[BrutalGoerge]

CGS|Todd Wrote:

BrutalGoerge Wrote:no matter what it seems, i do a new kernel, get 1000 fps, but loading times on the server are increased by a factor of 10.

I duno why I keep bothering. I never see a difference between 300FPS vs 1000. I don't think anyone else really does either. When people know their server is doing 1000 fps, their mind is tricked into thinking it's running better, much like a sugar pill.

if loading is slow you may be missing the native disk controller module.

but yes, 1000fps is mostly a sugar pill in my opinion. surely some 1000fps whore will post a flame about this comment, but in the end, 99% of people don't notice and/or care. if you are part of the 1%, more power to you, but its not what the masses need or want.

bottom line -- is it better, probably to some tiny degree . . . is it necessary, no.

im probably still not savvy enough at linux to be messing with this, but meh, if I mess it up, i can just format the thing and start new XD

how would I check to see if I have the native disk controller, and if not, how would I get it?

[BehaartesEtwas]

btw: why do you want to use 2.6.24 instead of 2.6.26? if 2.6.26 gives you ~1000 fps than just use that ^^

[janne]

BehaartesEtwas Wrote:btw: why do you want to use 2.6.24 instead of 2.6.26? if 2.6.26 gives you ~1000 fps than just use that ^^

I allways want to test the newest available

I do have 2.6.24.7-rt21 that produce ~970fps, but I cant get rt23 or rt24 to do it.
The newest rt25 just crashes when manipulating the real-time attributes of the processes with chrt.
Also 2.6.26.8-rt12 crashes when I chrt.

[bleomycin]

janne Wrote:Also 2.6.26.8-rt12 crashes when I chrt.

OOOOOO that was a close one, i was going to go ahead and run with that version tonight on my remote server but decided to check this thread real quick, glad i did!

[BehaartesEtwas]

never experiment with kernels unless you have at least some kind of rescue system ;-)

[Sir_knumskull]

what about

Code:

PIDS=`pidof srcds_amd`
for p in $PIDS; do
  sudo chrt -f -p 98 $p
done

and how to archieve 1000 fps on that f... amd? i only get stable 500 fps.
- Linux 2.6.26.8-rt12 #1 SMP PREEMPT RT Tue Dec 23 22:49:55 CET 2008 i686 GNU/Linux
- fps_max 0

what did i forget to do?

[Zentriple]

I am now using 2.6.26.8-rt12 and it works fine, but I can neither get more than 495 FPS. (CentOS, Intel Q6600)
I will see if I can get 2.6.26.6-rt11 and then try with that.

In the wiki-guide.. Maybe you could write a little about how to import settings from the old working kernel to the new. It took me 7 recompiles before I found out that.

UPDATE: The 2.6.26.6-rt11 were also running at 495 fps (but stable )

Someone who can tell me how to make it 1000 fps?

[BehaartesEtwas]

it seems, that on some amd systems things are a little different than on intel. at the weekend i was on a lan for which i had prepared a server on an usb drive. the system was some dual core amd. without players it ran fine with 1000 fps (but some drops to ~800). with players it wasn't stable at all. I had to run only one single server on the machine to keep it from dropping below 100 fps every seconds frame... fortunately on a lan high server fps are not so important so it was playable after all.
i really dont know what the problem was. i spent only few time to investigate, but i noticed that there were some clock sources missing (especially there was no hpet). maybe there are some mainboards for amd lacking an hpet clock? that *could* be the cause of the problem...

[bleomycin]

Zentriple Wrote:I am now using 2.6.26.8-rt12 and it works fine, but I can neither get more than 495 FPS. (CentOS, Intel Q6600)
I will see if I can get 2.6.26.6-rt11 and then try with that.

In the wiki-guide.. Maybe you could write a little about how to import settings from the old working kernel to the new. It took me 7 recompiles before I found out that.

UPDATE: The 2.6.26.6-rt11 were also running at 495 fps (but stable )

Someone who can tell me how to make it 1000 fps?

Depending on hardware i have had this problem when fully disabling acpi, re-enabling it got me back up to 990fps.