Swap - Slowly Increasing

[mfwade]

Does anyone know what would cause Swap to steadily increase over time? Currently Swap is consuming ~238mb of space.

Build: 16.1.1.20201028T105733.d127809143-1buster
Kernel: 4.19.0-11-untangle-amd64


Screen Shot 2021-01-21 at 11.13.51 AM.png

Thank you

[sky-knight]

You have 238.03mb of swap in use, my Untangle here has 1.55gb swap in use, another of my servers has 633.34mb of swap in use, and the smallest Untangle I have in service has 787.43mb of swap in use.

At this point I think it's safe to say simply Linux is being Linux. I don't see a problem here with the information displayed.

[mfwade]

Agreed. I was just curious as it has been steadily increasing. If it aint broke then....

Thanks for the follow up!

[jcoehoorn]

Once upon a time, Linux really hated swap, and any swap use at all was a bad sign. Those days are long gone, and recent Linux kernels will opportunistically put certain things in swap in order to potentially save time later. A certain small amount of swap use is now normal, and has been for a few years. Moreover, unless you have disk pressure Linux won't waste time cleaning up old swap data. So a certain amount of swap creep is also normal.

[donhwyo]

Does that also apply to wear on ssd's?

[sky-knight]

Yes, but modern SSDs are designed for that. Worrying about that is also a thing of the past.

And to be clear when I say modern I meant he first drives in this class were the Samsung 840s, that launched in 2013.

You'd have to have an SSD older than 7 at this point to even think about it. And if you do have an SSD that old, for $50 you can get a new one... REPLACE IT!

[mikeyscott]

My swap usage has climbed again, got another 8GB RAM coming as it's cheap, so the box will have 16GB by the end of the week. My Atom unit has 8GB, but that's on the side at the mo.

[ajaffarali]

I'm getting almosy hourly notifications on high swap usage. This started about 2 days back. Any idea where I can look to address this problem? I have the Home Protect Plus license. I have changed the swap usage to .35 to stop the alters but would like to get to the bottom of it.

Event Summary:
The current system state is: [ Load (1-minute): 0.72, Load (5-minute): 0.69, Load (15-minute): 0.63, Memory Free: 1427MB, Disk Free: 9174MB, Swap Used: 957MB ]

Event Details:
active hosts = 43
cpu system = 0.113623515
cpu user = 0.16223855
disk free = 8G
disk free percent = 35%
disk total = 25G
disk used = 16G
disk used percent = 65%
load1 = 0.72
load15 = 0.63
load5 = 0.69
mem buffers = 0
mem cache = 90M
mem free = 1G
mem free percent = 37%
mem total = 3G
mem used = 2G
mem used percent = 63%
swap free = 2G
swap free percent = 73%
swap total = 3G
swap used = 957M
swap used percent = 27%
time stamp = 2021-02-14 09:26:06.702

[jcoffin]

disk used = 16G
mem total = 3G
swap used = 957M
swap used percent = 27%

957M is not much swap. The reason for the alert is it is a large percent of the small disk.

[oj88]

Out of curiosity and for the Linux illiterate, is there an official Untangle documentation to modify this "swappiness" to something less aggressive?

I've read the Linux documentation on the matter up to the limit of my understanding but I still can't fathom why the kernel would decide to swap - at all - when there's still plenty of unused, infinitely-faster RAM available.