Interestingly, I found that I was able to do some overcommitting after all, somewhat to my surprise, as my earlier tests of open nebula 4.4 and 4.6 didn't seem to allow that. This is what I think is happening:
Beginning setup: Image datastore is on NFS, system datastore is on local disk, launching non-persistent image via CLONE operation in opennebula. DATASTORE_CAPACITY_CHECK = NO for both. Initial size of system data store, 450 GB. Max size of qcow2 image--262 GB Actuall size of qcow2 image on disk, unexpanded-2.6 GB Launch first VM--SCHED asks--does system datastore have 262 GB available? Yes. Launch second VM--SCHED asks--does system datastore have 262 GB available? Yes.. because first one hasn't expanded out. and so forth. That amount of overprovisioning is enough for our purposes--we can get 8-9 images (actually a lot more than that) into the datastore and will only get in trouble if our users all run out the file to full size, which most of them do not. The system runs out of RAM and CPU before it runs out of disk in this scenario. Steve Timm ________________________________ From: Ruben S. Montero [rube...@dacya.ucm.es] Sent: Wednesday, October 08, 2014 3:50 AM To: Steven C Timm Cc: Javier Fontan; users@lists.opennebula.org Subject: Re: [one-users] Thin provisioning and image size Hi Yes, the value for the size of the image is computed in libfs.sh (fs_size) for different file types. For qcow2 images: SIZE=$($QEMU_IMG info "$1" | sed -n 's/.*(\([0-9]*\) bytes).*/\1/p') I.e. the virtual size in bytes is used. As this is the max. value of the image it is not updated. Some thoughts: 1.- Using the max size, enables a proper enforcement of disk quotas. And so prevents a kind of DoS attack , when a user starts a VM and grows the disk over the size of the Datastore, effectively disabling the hypervisor. 2.- Initially we thought of updating the image size every time it is copied back to the image datastore, but this may conflict with the quota system, as mentioned above. 3.- If needed we could implement datastore over-commitment as we do with the hosts, i.e. extend the LIMIT_MB attribute to allow OpenNebula use more datastore storage. (See, http://docs.opennebula.org/4.8/administration/references/ds_conf.html) Cheers Ruben On Mon, Oct 6, 2014 at 7:45 PM, Steven Timm <t...@fnal.gov<mailto:t...@fnal.gov>> wrote: I am seeing the opposite problem in One 4.x and have been ever since we started testing it. When I do oneimage create using a qcow2 image, opennebula always reports the size as the absolute maximum to which the qcow2 file system could expand. This keeps us from being able to over-provision our disk on the VM hosts as we've done under Opennebula 3.2 for a long time. For instance: [oneadmin@fermicloud198 ~]$ oneimage show 5 IMAGE 5 INFORMATION ID : 5 NAME : SLF6Vanilla USER : oneadmin GROUP : oneadmin DATASTORE : cloud_images TYPE : OS REGISTER TIME : 10/03 16:31:31 PERSISTENT : No SOURCE : /var/lib/one/datastores/102/180caf99a13146dbd1b60593378d4479 PATH : /tmp/55c42a4cc7f87ea3390bc2bef14212c5 SIZE : 256G STATE : used RUNNING_VMS : 1 PERMISSIONS OWNER : um- GROUP : u-- OTHER : u-- IMAGE TEMPLATE DESCRIPTION="SLF6 Vanilla" DEV_PREFIX="vd" DRIVER="qcow2" EC2_AMI="YES ------------------------ [oneadmin@fermicloud198 ~]$ onedatastore show 102 DATASTORE 102 INFORMATION ID : 102 NAME : cloud_images USER : njp GROUP : oneadmin CLUSTER : cloudworker TYPE : IMAGE DS_MAD : fs TM_MAD : shared BASE PATH : /var/lib/one/datastores/102 DISK_TYPE : FILE DATASTORE CAPACITY TOTAL: : 7T FREE: : 1.6T USED: : 4.1G LIMIT: : - PERMISSIONS OWNER : um- GROUP : u-- OTHER : --- DATASTORE TEMPLATE BASE_PATH="/var/lib/one/datastores/" CLONE_TARGET="SYSTEM" DATASTORE_CAPACITY_CHECK="NO" DISK_TYPE="FILE" DS_MAD="fs" LN_TARGET="NONE" TM_MAD="shared" TYPE="IMAGE_DS" IMAGES 5 6 [oneadmin@fermicloud198 ~]$ onedatastore show 100 DATASTORE 100 INFORMATION ID : 100 NAME : localnode USER : oneadmin GROUP : oneadmin CLUSTER : cloudworker TYPE : SYSTEM DS_MAD : - TM_MAD : ssh BASE PATH : /var/lib/one/datastores/100/100 DISK_TYPE : FILE DATASTORE CAPACITY TOTAL: : - FREE: : - USED: : - LIMIT: : - PERMISSIONS OWNER : um- GROUP : u-- OTHER : --- DATASTORE TEMPLATE BASE_PATH="/var/lib/one/datastores/100/" DATASTORE_CAPACITY_CHECK="no" SHARED="NO" TM_MAD="ssh" TYPE="SYSTEM_DS" IMAGES [oneadmin@fermicloud198 ~]$ --------------------------------- Any suggestions? Steve On Mon, 8 Sep 2014, Javier Fontan wrote: Then the value makes sense as the units stored are Megabytes. On Fri, Sep 5, 2014 at 3:34 PM, Daniel Dehennin <daniel.dehen...@baby-gnu.org<mailto:daniel.dehen...@baby-gnu.org>> wrote: Javier Fontan <jfon...@opennebula.org<mailto:jfon...@opennebula.org>> writes: Which was the size of the original image? I think that when you do a save_as (deferred disk snapshot) it just copies the size of the original image to the new one. I started with empty qcow2 disk of several virtual sizes, but on disk they are all 196KB. Regards. -- Daniel Dehennin Récupérer ma clef GPG: gpg --recv-keys 0xCC1E9E5B7A6FE2DF Fingerprint: 3E69 014E 5C23 50E8 9ED6 2AAD CC1E 9E5B 7A6F E2DF _______________________________________________ Users mailing list Users@lists.opennebula.org<mailto:Users@lists.opennebula.org> http://lists.opennebula.org/listinfo.cgi/users-opennebula.org -- Javier Fontán Muiños Developer OpenNebula - Flexible Enterprise Cloud Made Simple www.OpenNebula.org<http://www.OpenNebula.org> | @OpenNebula | github.com/jfontan<http://github.com/jfontan> _______________________________________________ Users mailing list Users@lists.opennebula.org<mailto:Users@lists.opennebula.org> http://lists.opennebula.org/listinfo.cgi/users-opennebula.org ------------------------------------------------------------------ Steven C. Timm, Ph.D (630) 840-8525<tel:%28630%29%20840-8525> t...@fnal.gov<mailto:t...@fnal.gov> http://home.fnal.gov/~timm/ Fermilab Scientific Computing Division, Scientific Computing Services Quad. Grid and Cloud Services Dept., Associate Dept. Head for Cloud Computing _______________________________________________ Users mailing list Users@lists.opennebula.org<mailto:Users@lists.opennebula.org> http://lists.opennebula.org/listinfo.cgi/users-opennebula.org -- Dr. Ruben Santiago Montero Associate Professor (Profesor Titular), Complutense University of Madrid URL: http://dsa-research.org/doku.php?id=people:ruben Weblog: http://blog.dsa-research.org/?author=7
_______________________________________________ Users mailing list Users@lists.opennebula.org http://lists.opennebula.org/listinfo.cgi/users-opennebula.org
