Memory Problem

[z7917]

Hi.
I just installed ispCP omega.
Its like working smooth on my VPS but seems like it eats up so much RAM that the VPS crashes.
I have like 512mb and after Apache2 was started I have like 5 minutes to do this and that and after that its all working further but I'm kicked out of SSH as well as cannot login again.
When I try to start a new process i get: Cannot allocate Memory.
What actually makes no fun. Lol.

Is there any hint you can give me how to make sure that wont happen again? Cause I always need to ask my Host to reboot the VPS. thats not so cool.
Thanks for your Help.

[kilburn]

You should start by taking a look at the running ispcp on low-resource systems guide.

[rajkosto]

Is it an OpenVZ VPS ?
If it is, OpenVZ counts your used VIRTUAL memory as your memory limit. Most of the server services use a lot of virtual memory (run a lot of threads/processes) but a very small percentage of that is actually allocated physical memory/swap.
So, what i did for a LONG time on openvz, was to find which services use a lot of vram in TOP, then edit their init.d scripts, and add something like ulimit -s 512 as the first executable line
This reduces the thread stack from 8M vram to 512K vram, a 16x reduction !
Most important is to do this for apache2, then bind9, maybe mysql and proftpd.

It's a trick many people don't know, and simply think that they should upgrade their OpenVZ instance to one that has more RAM, and providers are using this property of OpenVZ to massively oversell their physical ram (which you cant do under XEN, vmware, etc).

Hope this helps