16.04 RAM usage excessive

[TWPonKubuntu]

16.04 has begun to show very high RAM usage. The biggest user is mysqld being run by akonadiserver.
The usage is steady at about 1.1GB (2.0GB system RAM available).

This high usage does not start on bootup, but after running a simple card game (KPatience) it jumps to the above value and even after closing the game, it does not decrease.

Running most other programs also cause the RAM usage to spike and remain in use.

I have had trouble with akonadi before, under 14.04, but it was "fixed" after being reported. The trouble then was excessive CPU usage, which is NOT the problem now.

FYI

[elijathegold]

I'm wondering if that's just the Buffers and Cache increasing. I'm running at about 3GB of 16GB used but free -m tells a different story.

free -m
              total        used        free      shared  buff/cache   available
Mem:          15963        2647       11321         426        [COLOR=#ff0000]1995[/COLOR]       12784
Swap:         16211           0       16211

[TWPonKubuntu]

That corresponds to my results:

free -m
total        used        free      shared  buff/cache   available
Mem:           3277        1020        1589           8         667        2209
Swap:          1929           0        1929

While my RAM widget is reporting 1.4GB total usage, with only Firefox 46 and Konsole running.

System Activity still shows mysqld using 823,617 KB, parent is akonadiserver. I think this is excessive.

[elijathegold]

It's probably part of the cache ready for mysqld to use if needed and as such will be freed when needed by something else. If it keeps ticking up at regular intervals then it may be a memory leak; in which case it is worth filing a bug report.

[Spadge]

Linux and other UNIX like OSes have always had a memory management philosophy of using RAM instead of Swap.

Only ever dump memory to Swap when you're out of RAM, it's not hurting anyone.

KiB Mem : 16415044 total, 11987532 free,  2434248 used,  1993264 buff/cache
KiB Swap: 16758780 total, 16758780 free,        0 used. 13564304 avail Mem

Swap is slow.

[Spadge]

Windows OSes have a philosophy of dumping Memory to Swap the second it's done with it.

Who is to say either philosophy is right or wrong?

On the one hand, stuff sits around in RAM until RAM runs out, is dumped into Swap where it can be retrieved slowly later. On the other hand, RAM is kept as free as possible and stuff is always being dumped into Swap and retrieved from it.

It's why UNIX like OSes generally benefit from having more RAM, and Windows OSes generally benefit from having faster disk drives.

[TWPonKubuntu]

This is not happening on 14.04, it is an artifact of the latest LTS release and it started recently.
I've been running 16.04, on a separate hard drive, since the beta was made available.

[elijathegold]

It sounds to me as if you have found a bug worth reporting to KDE project