----- Original Message -----
From: "Shu Ming" shuming@linux.vnet.ibm.com To: "Federico Simoncelli" fsimonce@redhat.com Cc: "VDSM Project Development" vdsm-devel@lists.fedorahosted.org Sent: Tuesday, February 7, 2012 3:23:37 PM Subject: Re: [vdsm] Live Merge and Storage Live Migration
On 2012-2-7 20:23, Federico Simoncelli wrote:
----- Original Message -----
From: "Shu Ming" shuming@linux.vnet.ibm.com To: "Federico Simoncelli" fsimonce@redhat.com Cc: "VDSM Project Development" vdsm-devel@lists.fedorahosted.org Sent: Tuesday, February 7, 2012 4:10:38 AM Subject: Re: [vdsm] Live Merge and Storage Live Migration
Sorry for confusing. Please let me explain my question again. In the Engine-VDSM Flow of "LiveMerge" wiki page, the engine will call the merge interface from engine to HSM to request the merge. I was wondering what HSM will do after it get the merge request. Does it call further interfaces in SPM by whatever way to make SPM to commit the real merge operation or just complete the operation by it self? If it does, how SPM will tell HSM the status of the merge operation? synchronizedly or asnchronizedly?
The merge operation is done on the HSM by the qemu process, no HSM-SPM interaction is required here.
In the future we might consider the mailbox as mean of communication between the HSM and the SPM, even though it's now enabled only for block storage domains (and if the irs.vol_extend_policy is ON).
Still the entry point would be the deleteVolume call on the SPM. Does it mean that deleteVolume call will be from HSM to SPM directly instead of from engine?
Yes but don't expect that anytime soon (as far as I know).