Hi, All. Is it possible to run vdsm without sanlock? We'd prefer to run libvirtd with virtlockd (lock_manager = "lockd") to avoid the sanlock overhead, but it looks like vdsmd / ovirt requires sanlock. Thanks, Devin
On Thu, Nov 5, 2015 at 11:33 PM, Devin A. Bougie <devin.bougie@cornell.edu> wrote:
Hi, All. Is it possible to run vdsm without sanlock? We'd prefer to run libvirtd with virtlockd (lock_manager = "lockd") to avoid the sanlock overhead, but it looks like vdsmd / ovirt requires sanlock.
True, we require sanlock. What is "sanlock overhead"? Nir
Thanks, Devin _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
Hi Nir, On Nov 6, 2015, at 5:02 AM, Nir Soffer <nsoffer@redhat.com> wrote:
On Thu, Nov 5, 2015 at 11:33 PM, Devin A. Bougie <devin.bougie@cornell.edu> wrote:
Hi, All. Is it possible to run vdsm without sanlock? We'd prefer to run libvirtd with virtlockd (lock_manager = "lockd") to avoid the sanlock overhead, but it looks like vdsmd / ovirt requires sanlock.
True, we require sanlock. What is "sanlock overhead"?
Mainly the dependence on a shared or remote filesystem (nfs, gfs2, etc.). I have no problem setting up the filesystem or configuring sanlock to use it, but then the vm's fail if the shared filesystem blocks or fails. We'd like to have our vm images use block devices and avoid any dependency on a remote or shared file system. My understanding is that virtlockd can lock a block device directly, while sanlock requires something like gfs2 or nfs. Perhaps it's my misunderstanding or misreading, but it seemed like things were moving in the direction of virtlockd. For example: http://lists.ovirt.org/pipermail/devel/2015-March/010127.html Thanks for following up! Devin
On Fri, Nov 6, 2015 at 5:59 PM, Devin A. Bougie <devin.bougie@cornell.edu> wrote:
Hi Nir,
On Nov 6, 2015, at 5:02 AM, Nir Soffer <nsoffer@redhat.com> wrote:
On Thu, Nov 5, 2015 at 11:33 PM, Devin A. Bougie <devin.bougie@cornell.edu> wrote:
Hi, All. Is it possible to run vdsm without sanlock? We'd prefer to run libvirtd with virtlockd (lock_manager = "lockd") to avoid the sanlock overhead, but it looks like vdsmd / ovirt requires sanlock.
True, we require sanlock. What is "sanlock overhead"?
Mainly the dependence on a shared or remote filesystem (nfs, gfs2, etc.).
There is no such dependency. Sanlock is using either an lv on block device (iscsi, fcp) or a file (on nfs, gluster) to maintain leases. If sanlock cannot access storage and maintain the lease, it is likely that your vm also cannot access storage and will pause soon. Anything else? Nir
On Nov 7, 2015, at 2:10 AM, Nir Soffer <nsoffer@redhat.com> wrote:
Mainly the dependence on a shared or remote filesystem (nfs, gfs2, etc.).
There is no such dependency. Sanlock is using either an lv on block device (iscsi, fop)
Thanks, Nir! I was thinking sanlock required a disk_lease_dir, which all the documentation says to put on NFS or GFS2. However, as you say I now see that ovirt can use sanlock with block devices without requiring a disk_lease_dir. Thanks again, Devin
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Devin A. Bougie -
Nir Soffer