Red Hat Bugzilla – Bug 624414
OOMKILL on VM with 768MB RAM and no swap
Last modified: 2010-08-16 10:23:29 EDT
Created attachment 438924 [details]
Description of problem:
I installed Fedora 14 Alpha RC4 DVD x86_64, using DVD as a package repository. I use KVM in virt-manager. The virtual machine has 768MB RAM assigned.
The installation fails on 'Out of memory', but only if I don't have swap partition created (very weird).
I used vnc for installation (all logs are from that attempt), but later I reproduced it also when using basic graphical installation. So it is probably not related to vnc.
The installation fails when installing selinux-policy-targeted package. It seems that package requires huge amount of memory and kernel OOMKILLs anaconda.
The weird thing is that the installation proceeds just fine if I have "use whole disk" disk layout (I use 7GB disk device in my VM). But when I create custom disk layout, create just a single 7GB large partition for / (no other partitions, no LVM, no swap, nothing), the installation fails on OOM.
Version-Release number of selected component (if applicable):
always, but correct setup is needed
Steps to Reproduce:
1. Use KVM VM in virt-manager using 768MB RAM.
2. Select custom disk layout, create a single partition (for /) over whole disk (7GB in my case), no LVM, no other partition, no swap.
3. Installation produces OOM on selinux-policy-targeted package installation.
768MB RAM is not enough for installation
768MB RAM is enough for installation
I tested the exactly same setup on VM with 1GB RAM and installation succeeds. Therefore the required amount of RAM is somewhere between 768MB and 1GB.
Created attachment 438925 [details]
Created attachment 438926 [details]
memory usage in the moment of OOM crash as seen by top
Oh, I think I get it know. If I create a swap partition in the installation process, that partition is available even for anaconda, right? That would explain why default disk setup works. But if I don't create swap partition, it has no swap to use and just halts.
That would mean that this bug report should be more appropriately called "768MB RAM is not enough for installation" or something like that. 768MB should be enough. (Do we have some official guidelines on that somewhere?)
It's really quite difficult to definitively say how much memory is required for installation. It depends on your architecture, what storage selections you make (certain storage programs require more memory), your packaging selections, etc. We have some guidelines, but we can't really say for sure whether you've got enough or not.
You're right, though - if you make a swap partition, anaconda will make use of that.