Red Hat Bugzilla – Bug 706328
with 25GB left kvm refused to create more guests
Last modified: 2011-08-15 11:39:55 EDT
Created attachment 500001 [details]
Description of problem:
Tried to create 1000 guests on the machine with 64 cores CPU and 512GB memory . But after successful creation of 512 guests , was told error: internal error Process exited while reading console log output: kvm_create_vm: Cannot allocate memory Could not create KVM context .
When the error happened , checked with free
# # free -lm
total used free shared buffers cached
Mem: 516238 490302 25935 0 1215 440519
Low: 516238 490302 25935
High: 0 0 0
-/+ buffers/cache: 48568 467670
Swap: 34239 0 34239
it says there are still 25GB left . command "top" shows every qemu-kvm process use 0.0% memory
And also atm , selinux status was Permissive .
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1.try to start 1000 guests on 512GB memory machine
each guest is with 512MB vMemory and 1 vCPU configured .
could you post /proc/meminfo and ps xav too, when this happens?
Created attachment 501038 [details]
ps -axv and /proc/meminfo
(In reply to comment #3)
> Could you also check if "echo 1 >/proc/sys/vm/overcommit_memory" workaround
> that and then everything works fine?
with echo command executed , still meet kvm_create_vm: Cannot allocate memory
Could not create KVM context errors
Given our strict 5.8 bug fixing criteria, it seems as if we can survive without handling this issue.