Swap space being eaten

Julianacat · 2017-06-04 21:33:14

I have 16gb of ram, when I reach 11gb the system starts swapping and becomes extremely slow due to it.
Ive tried making the cache pressure high, and setting the swap really low.
I use kde and I dont know of anything that could be eating ram on without being displayed on system monitor.
Here is what free returns. I think its cache but adjusting the pressure doesnt help.
[julianacat@Julian-ArchLinux ~]$ free -m
total used free shared buff/cache available
Mem: 16082 11176 237 3287 4669 1324
Swap: 31742 966 30776

fsckd · 2017-06-04 21:40:51

You're using more than 11GB. RAM is also being used for buffer/cache. You only have 237 MiB free. Hence it is swapping. There is not enough free RAM for the 966 MiB in swap.

JonnyRobbie · 2017-06-04 23:05:30

I also have a problem with system becoming basically unresponsive (to the point of having to cut the power off after several minutes of seemingly frozen system and nonstop HDD activity) when it starts swapping. I do have much less RAM however - 4GB.

There was also another problem. The system seemed to swap a lot of plasma shell components. So every time I wanted to lower the volume (for example), I had to wait for several seconds (during which a loud music blasted annoyingly out) until the plasma applet loaded and acted.

So I've tried to disable swap entirely. This somewhat fixed the second issue, but when the RAM runs out, the system basically also gets frozen (I guess kinda makes sense though).

What I don't understand is the extremely poor performance of the swap. I know old 5K4 HDD platters will be slower than RAM, but I don't think it is supposed to freeze the system entirely.

Julianacat · 2017-06-04 23:21:31

Isnt the buffer supposed to free itself for applications when needed?
I kinda need to use 13-14gb for applications. Maybe limiting buffer to 1-2gb but i have no idea how to do so.

I never had the problem on ubuntu, i could easily use up most of my ram without swapping.
Im using this to run 6 bots that consume 1-1.5 gb~ each and I would like for my entire system to not hang.

If I disable all my swap partitions, I wouldn't have any problems and i can use my full amount of ram without issues. but if i ever reach my limit, i wouldnt have a swap to buffer anything.

fsckd · 2017-06-05 00:15:02

You can try to drop the cache. Search https://www.kernel.org/doc/Documentation/sysctl/vm.txt for the section drop_caches.

seth · 2017-06-05 07:14:24

I'd check what's swallowing RAM... (and just blindly blame baloo or the indexer)

being displayed on system monitor

That is because all fancy indicators are fancy. And useless.
Try top and shift+m - the interesting column is RSS. The thing on top should be your browser (on a "normal" desktop setup)

There's in theory sufficiently available RAM (1324 MB) but the kernel doesn't swap around for no reason.
You in the past exceeded 16GB. The current load is lower, but you still have stuff swapped out that will only get swapped in when actually accessed.

Arch Linux

#1 2017-06-04 21:33:14

Swap space being eaten

#2 2017-06-04 21:40:51

Re: Swap space being eaten

#3 2017-06-04 23:05:30

Re: Swap space being eaten

#4 2017-06-04 23:21:31

Re: Swap space being eaten

#5 2017-06-05 00:15:02

Re: Swap space being eaten

#6 2017-06-05 07:14:24

Re: Swap space being eaten

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