Ok, i've started studying a few things, especially fastcgi, because after reading your messages, i'm starting to think that one of the scripts on a website is causing all this... anyway, in the meanwhile, it happen again... so i hope to give you a clearer view on this matter. There are about 50 pids for apache, and 50 for mysql. Top gives this: top - 09:01:05 up 14 days, 14:01, 0 users, load average: 36.45, 36.33, 36.48 Tasks: 232 total, 36 running, 196 sleeping, 0 stopped, 0 zombie Cpu(s): 52.1%us, 1.9%sy, 0.2%ni, 43.4%id, 1.6%wa, 0.4%hi, 0.4%si, 0.0%st Mem: 3115464k total, 2993804k used, 121660k free, 207764k buffers Swap: 5177336k total, 76k used, 5177260k free, 2039608k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 6343 apache 25 0 34148 15m 3540 R 19.6 0.5 0:05.49 /usr/sbin/httpd -k start -DSSL 27394 apache 25 0 41588 23m 4328 R 19.6 0.8 30:35.21 /usr/sbin/httpd -k start -DSSL 28396 apache 25 0 44904 26m 3692 R 19.6 0.9 24:19.87 /usr/sbin/httpd -k start -DSSL 28607 apache 25 0 34248 15m 3616 R 19.6 0.5 21:07.42 /usr/sbin/httpd -k start -DSSL 27235 apache 25 0 40412 22m 3868 R 9.8 0.7 19:15.02 /usr/sbin/httpd -k start -DSSL 1602 apache 25 0 34284 15m 3620 R 5.9 0.5 3:28.19 /usr/sbin/httpd -k start -DSSL 6322 apache 18 0 41236 22m 3676 S 2.0 0.8 0:00.78 /usr/sbin/httpd -k start -DSSL 1 root 15 0 2160 596 516 S 0.0 0.0 0:01.24 init [3] 2 root RT -5 0 0 0 S 0.0 0.0 0:00.00 [migration/0] [...] And here is a screenshot of server-status: www . supermariolovers.com/status.png These googlebot connections are not in time wait, and they're taking up a slot! So i guess it's entirely the script's fault... am i right? Cheers! On Fri, Mar 9, 2012 at 8:07 PM, Simone Frattegiani <simone.frattegiani@xxxxxxxxx> wrote: > Thank you so much for all your helpful advice! > > I'll take a few days to review all your suggestions and anylize the > problem, and i will let you know as soon as i'll have news! > > Cheers :) > > On Fri, Mar 9, 2012 at 2:01 PM, Tom Evans <tevans.uk@xxxxxxxxxxxxxx> wrote: >> On Fri, Mar 9, 2012 at 8:07 AM, Simone Frattegiani >> <simone.frattegiani@xxxxxxxxx> wrote: >>> Hello, >>> >>> i suddendly started having CPU load issues, like this: >> >> A couple of things: >> >>> Server-status shows this: >>> >>> […] >>> ReqPerSec: 6.37383 >>> BusyWorkers: 99 >>> IdleWorkers: 10 >>> Scoreboard: WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW >>> >> >> This is what worries me. You are handling 6.3 requests per second, but >> have 100 active workers handling requests. This means your requests >> are really, really slow. When requests are really slow, and the server >> gets a little busy, two things happen: >> >> 1) Requests take even longer to serve, as the resource contention >> (probably database) increases >> 2) Apache has to serve more simultaneous requests, and so has to have >> more children, which uses more CPU to start and run the processes, and >> more RAM is used on the new process. >> >> When this reaches the tipping point, which can be due to not enough >> RAM, not enough CPU, not enough IOPs, Apache has to start processes >> faster than it can serve requests, and load will metaphorically >> explode. >> >>> […] >>> The commands "netstat -a | grep 66.249" shows 20 connections from >>> googlebot ip, 1 in ESTABILISHEd status, the others in TIME WAIT. >>> >> >> So this may be largely irrelevant. If they are all in TIME_WAIT, then >> that is a keep alive connection. A keep alive connection isn't using >> your CPU, so it isn't slowing down your webserver. What it is doing is >> taking up a slot, which isn't ideal. >> >>> If i restart apache, everything gets back to normal. >>> >>> Any suggestions? >>> THanks! >>> >> >> I have a couple! >> >> First of all, you are using prefork MPM. This means to get an extra >> slot, apache has to fork and start up a new child. This is not >> efficient! If you use the worker or event MPM, then each child has >> multiple threads, and so you do not require to start, or keep >> starting, so many children. You will also have less CPU/RAM costs per >> slot. >> >> This will stop CPU usage exploding when a lot of requests come in, and >> hopefully you can serve requests faster. >> >> Finally, if you are worried about keep alive connections from google >> bot, you should seriously consider event MPM. This will use a single >> thread to handle ALL keep alive connections, waiting for a new request >> on it, and handing the request off to a different thread once there is >> data. This means you don't use multiple slots to handle keep alive >> connections. >> >> Finally, you don't mention it, but I assume you are running some web >> application, like PHP? I would recommend using fastcgi to host the >> application, divorce it entirely from apache. >> This will give you a clear idea of how much of your resources are >> being devoted to PHP, and will actually reduce the amount of resources >> over using mod_php. mod_php adds a PHP interpreter in every apache >> child, whether it is serving a PHP request, a static file from disk, >> or monitoring a keep alive connection. >> >> You can also strictly control how many PHP processes are used when >> running with fastcgi. >> >> Cheers >> >> Tom >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx >> For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx >> --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx
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