Sure, the load average is not perfect, but it is the best indicator you have to detect an overloaded machine.
How about your 50-60 instance, how much load they produce? > While load average is a useful guideline, it does not necessarily reflect > CPU usage in all cases (e.g lots of I/O bound processes waiting to run). > > Also it is an average over time (60 seconds). It can't tell you if within > the last 60 seconds that your CPU's were over saturated for a second while > a number of the games spiked due to simultaneous mob spawns because that > spike will get averaged out. The only way to see that is to sample more > frequently, which unfortunately puts more load on the system. Or as > someone else suggested, try playing on the servers to get an idea of the > servers responsiveness. > > The CPU usage of a L4D dedicated server will range from 15% of a 2.5GHz > core to 60%, and average around 22% based on my observations. The more > servers you run, the more likely you are to run into simultaneous spikes > and saturate your CPU. If I can gather enough data on the events that > cause spikes I am sure I can work a statistical model for calculating the > amount of CPU headroom you need. > > M. > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Ronny > Schedel > Sent: Wednesday, November 26, 2008 10:47 AM > To: Half-Life dedicated Linux server mailing list > Subject: Re: [hlds_linux] hlds_linux Digest, Vol 9, Issue 199 > > > It depends on how many cores/CPUs you have. In the SMP world, you can run > 4 > processes at 4 cores at the same time without any problem. Your load > average > is 4 or less, depending on how much load they consume. > > Optimum: > load average <= cores * CPUs > > Overload: > load average > cores * CPUs > > So, optimum for one Quad Core CPU is: > load average <= 4 * 1 > > This means not you can only run 4 L4D servers on one Quad Core, you have > to > look how the load is, because the servers does not run all the time, they > take some milliseconds sleep and other processes can run. Maybe you can > run > 6 or 8. > > >> Keep in mind that load average is an expression of queue depth. Some >> types >> of servers can handle deep queues with no visible impact shown to the end >> user. Gameservers are not that kind of animal. They require constant, >> nearly instantaneous updates in both directions in order to have truly >> smooth, seamless play. In the past, any time I saw load average above >> one >> I >> saw an impact of some sort. >> >> A load average above 3 seems to manifest itself in L4D servers in some >> unpredictable ways that can generally be ignored by most players. >> >> If you don't want to keep sending jarring notes that throw your players >> off, >> you really want to see your load average below 2. This should be true >> regardless of the number of CPUs that you have in your box. Thus, my >> comment in an earlier email about converting one of my public servers >> back >> over to Steam group only. Having 2 dedicated to just the Steam group >> will >> still let people fill up the public servers first and use the two >> semi-private ones as relief. >> >> >> [snip] >> >> >>> >>> ------------------------------ >>> >>> Message: 3 >>> Date: Wed, 26 Nov 2008 17:28:11 +0100 >>> From: "Ronny Schedel" <[EMAIL PROTECTED]> >>> Subject: Re: [hlds_linux] -fork configuration tip >>> To: "Half-Life dedicated Linux server mailing list" >>> <hlds_linux@list.valvesoftware.com> >>> Message-ID: <[EMAIL PROTECTED]> >>> Content-Type: text/plain; format=flowed; charset="iso-8859-1"; >>> reply-type=original >>> >>> >>> You have only 4 cores, with a load of 8 your server is overloaded. CPU >>> usage >>> does not matter these days, any new multicore CPU can handle Source >>> servers. >>> If you want lag free and smooth servers, your load average should not >>> exceed >>> your amount of cores. >>> >>> >>> > Our load average goes up to about 8. Given that we're running 12 >>> > instances >>> > on a quad-core, this doesn't bother me, and certainly performance is >>> > fine... >>> > I've seen the blood spatter effect too, but I don't think that's >>> > specifically performance related, it's just a glitch ;) >>> > >>> >> _______________________________________________ >> To unsubscribe, edit your list preferences, or view the list archives, >> please visit: >> http://list.valvesoftware.com/mailman/listinfo/hlds_linux >> > > > _______________________________________________ > To unsubscribe, edit your list preferences, or view the list archives, > please visit: > http://list.valvesoftware.com/mailman/listinfo/hlds_linux > > _______________________________________________ > To unsubscribe, edit your list preferences, or view the list archives, > please visit: > http://list.valvesoftware.com/mailman/listinfo/hlds_linux > _______________________________________________ To unsubscribe, edit your list preferences, or view the list archives, please visit: http://list.valvesoftware.com/mailman/listinfo/hlds_linux
