Thanks, this explains everything xD is there a way to tweak this 1GB number ? I don't get what this reserve is actually used for since from inside the VM I only see what I allocated, is it for the qemu process itself ?
For ZFS how much memory should I give it and what it depends on ? I tried to find more information on this but I have yet to find a useable formula to give me a precise idea. On 7 July 2015 at 12:38, David Finster <[email protected]> wrote: > For KVM based virtual machines, SmartOS will reserve <ram amount> + 1GB as > soon as the VM is started. The additional 1GB is to manage any potential > temporary overruns inside QEMU/KVM. > > So based on that, you actually created 4 x 3.5GB VMs which would require > 14GB. Keep in mind that ZFS relies on having a decent amount of RAM > available for it to function correctly - you don’t want to get into a > situation where a system has no free RAM (RAM used for ARC cache is > free-able). > > You can normally see if your hitting RAM availability problems by starting > the VM and going into /zones/<uuid>/root/tmp/vm.startvm.log. There you will > likely see the progress of locking memory. > > To make the best use of your resources, you should look towards either > native ‘joyent’ brand or ‘LX’ brand zones instead of KVM. Joyent zones are > the SmartMachines you get on Joyent Public Cloud and are a pretty friendly > UNIX environment to work with. LX zones on the other hand emulate a Linux > kernel, are newish and are quite a significant development focus at the > moment. > > - Dave > > On 7 Jul 2015, at 7:55 PM, Schmurfy <[email protected]> wrote: > > Hi, > > I was wondering if there is a way to know how much memory I can use for my > VMs, until now I am almost blind and sometimes it work sometimes it doesn't. > > Yesterday I tried to create 4 VMs with each 2.5 GB on a 16GB host and the > last one failed to provision, I had to reduce its memory to 2GB to make it > work, without that the VM was shown as runnning but was really not: "vmadm > info" hanged, no network up, "vmadm console "did nothing. > > In this case sometimes I see the provisioning of the VM failed (as shown > in vmadm list) and other times it appears to work but the VM is in a hald > dead state like above. > > We are a small company and we would really like to use as much as possible > our current hardware resources, that's why I am looking for a way to > estimate what ZFS and the host need/use. > > > *smartos-discuss* | Archives > <https://www.listbox.com/member/archive/184463/=now> > <https://www.listbox.com/member/archive/rss/184463/27127964-b8d97130> | > Modify > <https://www.listbox.com/member/?&;> > Your Subscription <http://www.listbox.com> > ------------------------------------------- smartos-discuss Archives: https://www.listbox.com/member/archive/184463/=now RSS Feed: https://www.listbox.com/member/archive/rss/184463/25769125-55cfbc00 Modify Your Subscription: https://www.listbox.com/member/?member_id=25769125&id_secret=25769125-7688e9fb Powered by Listbox: http://www.listbox.com
