CentOS 1000hz kernel help

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Edge100x
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Re: CentOS 1000hz kernel help

Post by Edge100x »

maggot wrote:I wasn't aware of "ip address". Pretty nifty :p Anyway, I see all of my IPs there and in the config, but only one reponds to pings. Is this normal?
They should all respond to pings, but if you just reinstalled, then you might be running into an issue with an old ARP cache entry on InterNAP's end. I'd recommend trying to ping a few other IPs on your subnet with commands like this -- it often resets the cache:

Code: Select all

ping w.x.y.253 -I w.x.y.z
ping w.x.y.254 -I w.x.y.z
Where w.x.y.z is the IP address that isn't responding to pings.
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Re: CentOS 1000hz kernel help

Post by maggot »

Edge100x wrote:
maggot wrote:I wasn't aware of "ip address". Pretty nifty :p Anyway, I see all of my IPs there and in the config, but only one reponds to pings. Is this normal?
They should all respond to pings, but if you just reinstalled, then you might be running into an issue with an old ARP cache entry on InterNAP's end. I'd recommend trying to ping a few other IPs on your subnet with commands like this -- it often resets the cache:

Code: Select all

ping w.x.y.253 -I w.x.y.z
ping w.x.y.254 -I w.x.y.z
Where w.x.y.z is the IP address that isn't responding to pings.
That fixed it right up, I can ping those addresses now. I can SSH on them now as well :) Will I have to do this every reboot, or does this just fix something on Internap's networking side?
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Re: CentOS 1000hz kernel help

Post by Edge100x »

maggot wrote:That fixed it right up, I can ping those addresses now. I can SSH on them now as well :) Will I have to do this every reboot, or does this just fix something on Internap's networking side?
This clears out the stored MAC address on their side and it's something that you'll only have to do once with this install. The MAC address changed when your OS was reinstalled, which is why it started occurring (they were still trying to send the traffic to your old MAC).
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Re: CentOS 1000hz kernel help

Post by maggot »

Ah, gotcha. Makes sense now :p I'm having trouble setting the "chrt" via GameCP, but it has a priority setting (which I assume uses nice). Is nice good enough, or is chrt preferred?
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Re: CentOS 1000hz kernel help

Post by Edge100x »

Setting the process to realtime is necessary to remove the timer slack (the kernel approximates timers more without it, leading to a fluctuating, lower FPS). "nice" doesn't accomplish this, so you'd need to chrt them by hand, or edit the control panel to do it.
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Re: CentOS 1000hz kernel help

Post by maggot »

Okay, thanks a lot for the help. Without fixing the timer slack, it's getting anywhere from 560 to 950 fps. I'm off to figure out this GameCP mystery!
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Re: CentOS 1000hz kernel help

Post by Edge100x »

One other thing you can try, to see if it makes a difference, is HPET (another timer source). You can find this option under the "Advanced" section of the "Server control" page.
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