Upgraded to 5.0, nodes seem to want to SWAP more

BloodyIron

Renowned Member
Jan 14, 2013
336
34
93
Recently upgraded from 4.4 to 5.0-23/af4267bf, and now my nodes are putting more into SWAP than before, even though they're at about 50% RAM usage on each node. This is really annoying as this can lead to higher IO latency, and I periodically flush my SWAP back to RAM in times like this.

Sure, my nodes swapped when I was on 4.4, but only when I was more in the realm of 80% of RAM being used or more on each node, not at 50%. And The amount being put into SWAP is not "small", I'm seeing 500MB to over a gig at times.

What's all this about then?
 
And? I'm not seeing how this is relevant to a change in swapping behaviour with a major release upgrade...
Thats not, but set swap to 0 should solve it too. I could see no difference. Between 4 and 5.
What says "sysctl vm.swappiness"?
 
I don't want it to _NEVER_ swap. I am capable of changing the swappiness parameter, I just am more reporting that the swapping behaviour seems to happen (by default/OOTB) earlier than it should. It seems like adjusting the "sane defaults", might be a good idea, or this might be an unforeseen outcome of something else.

Thats not, but set swap to 0 should solve it too. I could see no difference. Between 4 and 5.
What says "sysctl vm.swappiness"?
 
I don't want it to _NEVER_ swap...

Logical solution would be to disable swap at installation. I tried it and set swap size to zero, yet PVE 5.0 installer created 2GB swap. Why? I have plenty of RAM, so why Proxmox is forcing me to have swap anyway?