problem with hotplug and 64GB ram

the more ram you assign, the bigger the DIMMs that get plugged get -> 64G already means 2G dimms, and the alignment makes it so that 64G is not a valid choice, but 65G is.
 
  • Like
Reactions: Stone
I am having the same issue and can't set more than 44GB of RAM.
Trying 65GB I get the error:
kvm: -device pc-dimm,id=dimm59,memdev=mem-dimm59,node=3: a used vhost backend has not enough free memory slots left
TASK ERROR: start failed: QEMU exited with code 1

(Running 8.3.0)
 
I am still having this problem on PVE 8.3.2.

My max_mem_regions is set to 509 in vhost.conf. What should it be changed to?

I need hotplug and 64 GiB of memory. Is setting max_mem_regions the answer? I know 65 GB works, but I have 250+ VMs to create, so that jump from 64 GiB to 65 GiB means an additional 250 GiB of total memory. (not all on one host mind you.)
 
the more memory you assign, the coarser the granularity will get. at those sizes, the granularity is 2G. you can either choose 63 or 65.
 
Seems like the error message could be improved on. Maybe with a suggestion of memory values to pick. The memory size input field has up and down arrows to increase or decrease the memory in 32 byte intervals. Can we make these arrows suggest working values?

Is there a chart or graph show the granularity changes per GB of memory? Or a formula?
 
You must log in or register to reply here.
Top Bottom