LinuxMCE Forums

General => Users => Topic started by: cfernandes on August 05, 2012, 07:27:47 PM

Title: Memory Usage
Post by: cfernandes on August 05, 2012, 07:27:47 PM
Hello ,

someone is having problems with memory, my core all md's are using 100% of memory
i have  on core a  dell optiplex 755 with 4G  and 5 optiplex gx620 with 2g as a MD.

system is to slow  after 1 hour of usage .
Title: Re: Memory Usage
Post by: Marie.O on August 05, 2012, 07:56:54 PM
It is not unusual for a Unix system to use all available memory. See http://serverfault.com/questions/67759/how-to-understand-the-memory-usage-and-load-average-in-linux-server
Title: Re: Memory Usage
Post by: JaseP on August 06, 2012, 02:36:25 PM
@cfernandes:

You might want to adjust swappiness on the MDs,... High swappiness is more of a indicator of sluggishness on Linux systems than RAM usage. You might want a swappiness setting of 5 vs the default 60 as the MDs are net boot systems.

See here:
http://askubuntu.com/questions/103915/how-do-i-configure-swappiness

I don't know if it will be a huge difference, but most who lower swappiness report it being more responsive, with desktop systems.
Title: Re: Memory Usage
Post by: hari on August 07, 2012, 03:56:29 PM
be happy that the smart system utilizes your memory :-) It would be a bad investment if the RAM were idling unused, right?

@jasep
there should be no need to tune the swappiness on LMCE. We don't run workloads that go beyond installed RAM. So most of the RAM is used as cache anyway and there is no need for heavy paging. I'd refrain from giving such tuning advice to not so experienced users. They will be fine with the default settings.
Title: Re: Memory Usage
Post by: cfernandes on August 07, 2012, 06:08:00 PM
well then I must find that leaving it too slow
Title: Re: Memory Usage
Post by: JaseP on August 07, 2012, 06:34:50 PM
@cfernandes;

When you notice the system starting to slow down,... {Alt}{Ctrl}{F1} to a terminal and use the top command to see what is running. Given what Posde is saying, your RAM and swapping is not what is likely causing the slowdown. I suspect something else, like a misbehaving application of some kind. Please, especially, report if with top, if you see any of the following running:

The foregoing programs are KDE desktop related programs that are tied into KDE's "social desktop" schema. They scan the available drives for metadata related to contact information and feed it into Kontact, the KDE PIM software. If any part of the KDE desktop is run, or invoked somehow, these will activate and start eating up CPU cycles and IO bandwidth. On anything short of an i7 quad core with 8GB of RAM, they will grind the system to a functional halt. In Kubuntu 10.04, the versions of these "utilities" are especially poor/buggy, and pretty much need to be deactivated entirely (someone,... Posde or Thom, or someone,... confirmed they are not used in LinuxMCE for anything).

But if don't see any of the programs listed above, please report anything you do see that is using a large portion of resources.
Title: Re: Memory Usage
Post by: cfernandes on August 11, 2012, 04:26:23 PM
i do a rebuild on MD  and now is working,  thank you