Memory leak on 8.08 LTS server

[paj26]

I'm running 8.08 LTS, apache2 with php5, rails, and mysql. I have to restart about every 24 hrs as the memory slowly gets eaten up. Watching top, it jumped about 100mb in less than an hour. How can I diagnose/trace this? I'm running apache 2.2.8

[robgolding63]

Is the swap being used at all? If not, this is just the way Linux handles the memory. I just tried quickly to find an article for you but haven't had any success.

Basically, you can expect to see 98-99% memory usage on a Linux server, without alarm. If the swap starts being used then you know you have a problem. Thinking about it, this behavior makes perfect sense - the RAM is the fastest storage available to the system, so why not use it as much as possible? If another application requires some RAM, the O/S will release it as needed.

Hope this helps!

Rob

[paj26]

Not sure about swap space, I'll let you know tomorrow. I thought with a server running just those processes that once they were started, that the memory usage should be relatively constant, but I'm not an expert on it. Thanks for the info

[windependence]

http://thelinuxnewbie.blogspot.com/2006/08/linux-uses-too-much-memory-very-basic.html

http://www.novell.com/coolsolutions/qna/2327.html

http://softwaretracker.blogspot.com/2007/08/understand-why-linux-uses-up-all-memory.html

HTH,

-Tim

[paj26]

Here's what top looks like right now...

top - 07:43:07 up 1 day, 10:33, 2 users, load average: 0.02, 0.03, 0.00
Tasks: 114 total, 2 running, 112 sleeping, 0 stopped, 0 zombie
Cpu(s): 2.3%us, 0.3%sy, 0.0%ni, 96.7%id, 0.3%wa, 0.0%hi, 0.3%si, 0.0%st
Mem: 3631392k total, 3463588k used, 167804k free, 93872k buffers
Swap: 995988k total, 38656k used, 957332k free, 1826596k cached

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
21398 david 20 0 49204 35m 2400 S 1.3 1.0 1:48.46 ruby1.8
7959 david 20 0 48020 34m 2396 S 0.7 1.0 0:41.26 ruby1.8
9648 www-data 20 0 23056 8036 4220 S 0.7 0.2 0:00.28 apache2
9687 www-data 20 0 23632 7932 4036 S 0.7 0.2 0:00.12 apache2
9735 www-data 20 0 23632 8124 4060 S 0.7 0.2 0:00.12 apache2
9745 www-data 20 0 23088 7708 3936 S 0.7 0.2 0:00.04 apache2
1 root 20 0 2980 1864 544 S 0.0 0.1 0:01.02 init
2 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 kthreadd
3 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/0
4 root RT -5 0 0 0 S 0.0 0.0 0:00.02 watchdog/0 ....

[hyper_ch]

(1) use brackets... makes it easier to read
(2) what does free -m return?

[paj26]

$ free -m
total used free shared buffers cached
Mem: 3546 3373 172 0 132 1682
-/+ buffers/cache: 1559 1986


If I have free memory, why would it go into swap, unless it puts idle processes into swap?

[hyper_ch]

as you can see 1.6 gb ram is cache....

unused ram is wasted ram.