High RAM use in 16.04 on 64-bit System

[BlueAZ]

Hi, I'm noticing much higher RAM use in 16.04 on my 64-bit AMD system. I've used LTS versions of Ubuntu for over 5 years now and never had this problem before. I have a system load indicator, so I can see it graphically all the time. It seems to just keep increasing and doesn't go down again. This results in program screens graying out when I start them or ask them to do anything. I can't have more than one program open at a time, or things really freeze up or crash.
I've searched and found this on Launchpad: Ubuntu 16.04 Unity desktop uses much more ram Bug #1572801

Many others having this problem, but no real solution yet. Like others, I have checked System Monitor and found many derivations of 'Evolution' running and eating up large chunks of RAM. I looked it up and realized I could get rid of it, as I don't use it. But when I used Synaptic to find Evolution listings, mark them all for removal, and click 'Apply', it told me that 90 new things would be downloaded & installed along with the 8 or 10 Evolution things being removed. I couldn't find a way to not acquire all this new stuff I didn't understand, so I canceled it.
At this point, it would be nice if someone qualified & knowledgeable could take a look at this... Please?

[karl96]

Strange, i've heard of metapackages threatening to remove large amounts of packages but not the other way around. Possibly you have a broken system in terms of packaging (when did you last update?) which is why it requires all of this new stuff.

It actually isn't that important if it does pull it in, as long as the services are disabled they'll just consume disk space instead of ram.

to check for broken dependencies
Run

 apt-get check

or

 apt-get -f remove evolution

. I use

 apt-get install --no-install-recommends

to prevent installing recommended packages but not entirely sure on packages being pulled in on removal.

Do you have swap space? You could simply extend your swap partition to bypass the issue.

[BlueAZ]

Thanks! Here's what I get when I run that first code:

 -A:~$ apt-get check
E: Could not open lock file /var/lib/dpkg/lock - open (13: Permission denied)
E: Unable to lock the administration directory (/var/lib/dpkg/), are you root?

When I've tried to remove Evolution in the Terminal, it just tells me that no such package is installed (?!!?) But I am able to Kill the Evolution processes within the System Monitor.
Still using to much RAM. Can I kill the process Compiz?
Thanks again, Blue

[karl96]

Run

whereis evolution

There must be a binary on the system somewhere, manually deleting it will prevent it from launching.

Edit:
Compiz is a window manager, if you're using Compiz as your main window manager killing it is a bad idea, but if not yes, it is quite a demanding window manager and unnecessary to many.

Edit 2:
Manually deleting binaries should only be done when the packages are broken.

[BlueAZ]

Thank you Karl96. I ran the whereis evolution command and was directed to /usr/lib/evolution. I went there and found 2 folders, one just named Evolution and another named EvolutionData... But I could not remove them. (Move to Trash was grayed out, couldn't use Shift-Delete, even on the individual files within.) So I don't know how to manually delete them.
Does this have to do with the earlier code response about /var/lib/dpkg/lock - open ? And the Terminal asking me if I was root? I'm the sole owner and user of this computer. Do I have to become root to root out Evolution?!
Also, if Compiz is so demanding, is there another window manager I could use instead? I don't do any complex gaming or 3D stuff.
Again, Many thanks, Blue

[cariboo]

What do you consider high ram usage? Running:

free -m

in a terminal I get the following result:

free -m
              total        used        free      shared  buff/cache   available
Mem:          15942        2572         803          76       12566       12959
Swap:          1999           8        1991

As you can see my system is using 2573MiB running Chromium, Thunderbird, Serviio and an open terminal. I still have over 12GiB buffered/available.

[BlueAZ]

Thanks cariboo, This a.m. I was notified of an update to 4.40-53 and did it. At the time, my system was showing a RAM use of 4 Gb + 2 Gb of swap with NO open programs. I managed to get & install the update, had to try 2x to restart and now memory use is lower. So maybe the problem was fixed in this new kernel update. System is now using less than 2 Gb RAM and no swap, with Thunderbird and Firefox open. This is a big improvement, and I hope it lasts!
I'll keep the forum posted.

[karl96]

Hi, you'll need to be root to delete system wide files, /var/lib/dpkg/lock just means apt is already in use, could possibly be stuck or updating in the background. Evolution shouldn't be in /usr/lib though (the libraries should), the binaries should be in /usr/bin (I think?), it won't be able to run without the libraries either so it should work though.

[BlueAZ]

OK, this issue seemed to be resolved for several months, but is now back! I keep 16.04 updated daily, and the high memory use started a few days ago. Nothing else on my system has been changed, just regular updates. This time, so much of my 4 Gb of RAM is getting used that screens gray out for half a minute before showing up normally. These are programs and websites I frequently use, so I can tell the difference. And a check of System Monitor shows that absolutely 0 Swap is in use while this is happening, a new wrinkle since last time.
I am still unable to make up my own Terminal entries beyond 'sudo apt-get update', so please keep it simple.
Thanks!

[vocx]

OK, this issue seemed to be resolved for several months, but is now back! I keep 16.04 updated daily, and the high memory use started a few days ago. Nothing else on my system has been changed, just regular updates. This time, so much of my 4 Gb of RAM is getting used that screens gray out for half a minute before showing up normally. These are programs and websites I frequently use, so I can tell the difference. And a check of System Monitor shows that absolutely 0 Swap is in use while this is happening, a new wrinkle since last time.
I am still unable to make up my own Terminal entries beyond 'sudo apt-get update', so please keep it simple.
Thanks!

I suggest you install "htop". It is a program, that like system monitor, shows what processes are under use, but in the terminal. You can sort the programs by CPU use or Memory, and also terminate (kill) programs. This is useful if you see a runaway program suddenly taking a lot of resources.

sudo apt install htop
htop

I think System Monitor shows only the processes run under your name, but "htop" shows also those by the "root" user, that is, the system itself. If a program by root is taking a lot of CPU processing power or RAM it may be a background process, and that is usually Xorg or Compiz, which deal with the graphics you see on the screen. You should check your graphics card, to see which drivers are installed. Maybe if you use restricted drivers, you will notice your system is more responsive, as the CPU doesn't need to work that hard to render your screen. Graphical programs, videos, flash applications, and things like that, may cause lockups because they are notorious memory consumers, and if your graphics card or your flash version, for example, are buggy, you may experience these problems.

By the way, I just mention this, using a lot of RAM is not a problem itself. Linux uses a lot of RAM because it caches most of it for future use. Of course, if you really get the gray screen behavior, this is a problem. It is either running out of memory, or the CPU cores are maxed out (running each core at 100%, for example). You can use "htop" to verify this.