Hi Enzo, just go to table/view "disk_offering_view" and in the field "cache_mode" insert "writeback" value....
Be aware, that if using writeback cache with CEPH - this is not really needed, and perhaps better to use RBD cache on ceph.conf on KVM side... Also note, with writeback cache set - if using NFS as storage - live migrations will not work ! With ceph and writeback cache, live migration works (libvirt limitation, you can google it). Best, Andrija On 24 August 2016 at 10:24, (IMIS) Enzo Bettini <[email protected]> wrote: > Hi Andrei, > > How did you get around this? Did you manually update the VM configuration > using virsh edit? > > Regards, > Enzo > > > On 15/05/2016 00:31, Andrei Mikhailovsky wrote: > >> Not as far as I know (. The ticket status is closed >> >> Andrei >> >> ----- Original Message ----- >> >>> From: "Simon Weller" <[email protected]> >>> To: "users" <[email protected]> >>> Sent: Thursday, 12 May, 2016 14:38:35 >>> Subject: Re: KVM disk cache option has no effect >>> All, >>> >>> Is there a current issue in Jira on this? >>> >>> - Si >>> >>> >>> >>> >>> >>> ________________________________________ >>> From: Yuriy Karpel <[email protected]> >>> Sent: Thursday, May 12, 2016 7:07 AM >>> To: [email protected] >>> Subject: Re: KVM disk cache option has no effect >>> >>> The same function does not work on centos + ceph. CloudStack 4.7.1 >>> >>> 2016-05-12 14:29 GMT+03:00 Andrei Mikhailovsky <[email protected]>: >>> >>> Hi Shweta, >>>> >>>> thanks for your findings. I am very much surprised to see this was not >>>> discovered earlier, especially since this feature has been implemented >>>> many >>>> versions back (back in version 4.4 or 4.5 i think). I was under the >>>> impression that people are testing and reporting on the new features >>>> before >>>> they hit the release, which apparently is not the case, at least for >>>> some >>>> new features. From what I can see this feature was completed about a >>>> year >>>> ago. >>>> >>>> I've tried to reopen this issue, but i don't have the rights due to the >>>> Jira being in a temporary Lockdown mode. >>>> >>>> Could someone with the right access reopen this issue on the grounds >>>> that >>>> it was reported (by at least two individuals) that this feature is not >>>> working. >>>> >>>> Many thanks >>>> >>>> Andrei >>>> >>>> ----- Original Message ----- >>>> >>>>> From: "Shweta Agarwal" <[email protected]> >>>>> To: "users" <[email protected]> >>>>> Sent: Thursday, 12 May, 2016 12:02:59 >>>>> Subject: RE: KVM disk cache option has no effect >>>>> Hi Andrei, >>>>> >>>>> Few days back I was also doing some testing in this area and then we >>>>> >>>> found out >>>> >>>>> that cache field in disk offering is just a UI or API parameter. But in >>>>> >>>> actual >>>> >>>>> implementation of the API we are just neglecting this parameter . So >>>>> effectively these parameters in disk offering does nothing . >>>>> >>>>> Thanks >>>>> Shweta >>>>> >>>>> -----Original Message----- >>>>> From: Andrei Mikhailovsky [mailto:[email protected]] >>>>> Sent: Thursday, May 12, 2016 4:07 PM >>>>> To: users >>>>> Subject: KVM disk cache option has no effect >>>>> >>>>> Hello >>>>> >>>>> I've been trying to use cache = writeback option for my KVM hypervisor >>>>> >>>> with ceph >>>> >>>>> backend storage. However, when I am launching a vm that uses the disk >>>>> >>>> offering >>>> >>>>> with cache=writeback, the cache setting is still set to =none according >>>>> >>>> to the >>>> >>>>> ps aux command.The same applies to the root as well as additional data >>>>> >>>> volumes. >>>> >>>>> I am using ACS 4.7.1, both management and hypervisor servers are Ubuntu >>>>> >>>> 14.04. >>>> >>>>> >>>>> Could someone please advise on how enable writeback cache? >>>>> >>>>> Cheers >>>>> >>>>> Andrei >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> DISCLAIMER >>>>> ========== >>>>> This e-mail may contain privileged and confidential information which >>>>> is >>>>> >>>> the >>>> >>>>> property of Accelerite, a Persistent Systems business. It is intended >>>>> >>>> only for >>>> >>>>> the use of the individual or entity to which it is addressed. If you >>>>> are >>>>> >>>> not >>>> >>>>> the intended recipient, you are not authorized to read, retain, copy, >>>>> >>>> print, >>>> >>>>> distribute or use this message. If you have received this communication >>>>> >>>> in >>>> >>>>> error, please notify the sender and delete all copies of this message. >>>>> Accelerite, a Persistent Systems business does not accept any liability >>>>> >>>> for >>>> >>>>> virus infected mails. >>>>> >>>> > -- Andrija Panić
