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Question About Memory Slab Growing up to occupy all memory

alecaus

New Pleskian
Honestly, I don't know if this is the best place to post this. And if not, if you can point me to an ideal place, I appreciate it.

I don't know if it's a Plesk problem, I confess I don't believe it is, but there it goes.

The slab memory keeps growing on the server, until it takes up all the memory and leaves the memory free at only 100 ~ 200mb.

This worries me, as I am having to restart the server as soon as I notice that it occupies all the memory, and this can certainly cause performance or response problems.

I wonder, what ways could I debug, go after the source problem?
(I uploaded a photo to demonstrate what really happened.)

CentOS7
Plesk Obsidian 18.0.29
Linux SystemMemory Slab.png
 
slab is some kind of cache, so it is supposed to grow as long as there is free memory. Just like buffered & cached, it should be reclaimed if it is needed for something else.
Do you actually notice any performance problems or do you restart anyway? If the former, you should look into top, slabtop, and maybe iotop for some application rapidly allocating and freeing lots of memory.
 
I used the commands below to check the data information, and I did not notice any abnormalities (I am a layman in these analyzes), but honestly I have not noticed any performance problem. My problem is to have, I increased the memory from 4GB to 8GB just because I was having problems with 4GB, but for now everything is ok.

If you notice something strange in the image, or want to make a comment, welcome. Thank you


1597791398989.png

1597791477142.png
 
I am having the same problems see below the very low point is the server restart. However it appears it does not impact on the server performance
1597820763119.png
Can anyone offer a monitoring settings to show the real RAM usage?
 
I used the commands below to check the data information, and I did not notice any abnormalities (I am a layman in these analyzes), but honestly I have not noticed any performance problem. My problem is to have, I increased the memory from 4GB to 8GB just because I was having problems with 4GB, but for now everything is ok.

Then you need not worry, this is normal. You do not use swap, the reported actual RAM use in the second screenshot is below 1GB, it's just cache using up everything that isn't needed otherwise.

I am having the same problems see below the very low point is the server restart. However it appears it does not impact on the server performance

You, however, seem to just barely reach into swap, so you might want to consider adding RAM. For more details, post /proc/meminfo.
 
adding RAM?? I have huge amounts of free server RAM.
The issue is this resource reporting tool
Thanks
 
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