Memory use

[Viking0]

Hi.

I tested my new server sending 5000 local mails.
It took it 15 min to send them all and clean the queue.
When during this task I noticed that the memory use went to 5 GB.
30 min. after this test, the server still uses 5 GB of memory.

Is this normal?
At some point is it going to release that memory??
is possible to improve this?


Thanks.

PD. Sorry for my bad english

[dijichi2]

define memory use

[Viking0]

Before I did this test it was using 1 GB of memory


root@correo1:~# free
total used free shared buffers cached
Mem: 8308328 4989552 3318776 0 309664 2271544
-/+ buffers/cache: 2408344 5899984
Swap: 15623204 0 15623204

[Viking0]

After 90 min the server still using 5 gb of ram.

root@correo1:~# free
total used free shared buffers cached
Mem: 8308328 4993256 3315072 0 311916 2273180
-/+ buffers/cache: 2408160 5900168
Swap: 15623204 0 15623204

[bdial]

if it makes you feel better i have 190 users amd i'm currently using almost all of my 16GB of ram. I think thats just hte nature of linux. if it has the ram, it'll use it.

[Viking0]

After several hours I restarted Zimbra and it finally relased the memory it was not using.

bdial,
I'm not an expert but I don't think it is a Linux problem, but a Zimbra problem, I have other linux server and they dont behave the same way, they don't waste memory like this.

Has anyone solved this on their servers.
Some config to change???
anything???

[bdial]

go to the zimbra wiki, there are several performance tuning guidelines.

i'm typing this on my linux laptop. it's a opensuse box running kde. i have firefox, a couple of xterms, and a few docked apps running. i'm currently using 1.7G out of 2GB of ram. my system isn't running "slow" though.

i'm no expert on ram usage in linux either, but it seems like every linux box i've used has had high memory usage. it's fine usually it's when the system starts to swap that worries me.

[rotorboy]

Hi Viking0,
I agree with Bdial... on my CentOS machines I see this same issue with Zimbra and a few other applications we run on other machines. When the RAM is needed, they scale up use and when the RAM isn't needed, it allows the RAM to stay available for the application - unless something comes along that needs the RAM.

This has caused us 0 problems so far...

[knabe]

I currently have 25 users on a server with 8GB of RAM and after a couple of days the java process starts using SWAP which is causing high IO and terrible performance. I am on 5.0.9. Memory leak?

[dijichi2]

linux is designed to use as much memory as it can - the philosophy is that you buy RAM to use it, not to sit there doing nothing. so while free/top/etc will happily report 100% usage all day, in actual fact most of it is usually being used for caching. it's only if the box starts to swap that you have problems. if you look at /proc/meminfo and look at the cache/dirty/clean fields - google for an explanation - you'll usually find that only a small amount of the memory is actually locked.