Can host hooks be used to implement the following policy to avoid "boot storm"? 1.count and sort VMs awaiting for boot. 2.If the count is less than or equal to, for example 5, then boot all VMs and exit the script. 3.Otherwise, boot and dequeue vm0 to vm4, and minus the count by 5. 4.Sleep some time, and go to step 2. _______________________________________________ Users mailing list Users(a)ovirt.org http://lists.ovirt.org/mailman/listinfo/users

On 05/23/2013 04:23 PM, lofyer wrote: > Can host hooks be used to implement the following policy to avoid "boot > storm"? > > 1.count and sort VMs awaiting for boot. > 2.If the count is less than or equal to, for example 5, then boot all > VMs and exit the script. > 3.Otherwise, boot and dequeue vm0 to vm4, and minus the count by 5. > 4.Sleep some time, and go to step 2. > _______________________________________________ > Users mailing list > Users(a)ovirt.org > http://lists.ovirt.org/mailman/listinfo/users hooks run one on vm-start one by one. would be a bit tricky to do the above. roy - didn't you add some mechanism to throttle boot storms in the engine?

On 05/26/2013 09:59 AM, Roy Golan wrote: > On 05/24/2013 03:22 PM, Itamar Heim wrote: >> On 05/23/2013 04:23 PM, lofyer wrote: >>> Can host hooks be used to implement the following policy to avoid >>> "boot >>> storm"? >>> >>> 1.count and sort VMs awaiting for boot. >>> 2.If the count is less than or equal to, for example 5, then boot all >>> VMs and exit the script. >>> 3.Otherwise, boot and dequeue vm0 to vm4, and minus the count by 5. >>> 4.Sleep some time, and go to step 2. >>> _______________________________________________ >>> Users mailing list >>> Users(a)ovirt.org >>> http://lists.ovirt.org/mailman/listinfo/users >> >> hooks run one on vm-start one by one. would be a bit tricky to do the >> above. >> roy - didn't you add some mechanism to throttle boot storms in the >> engine? > yes at RunVmCommandBase.delay(Guid vdsId) - but it doesn't fit here. > It'll delay the VM run only when there is no free memory to run the VM > and will wait till engine signals after gathering statistics of > powering up VMs. lofyer - any other issue other than memory bottleneck you were trying to resolve? Thanks, Itamar

于 2013/5/26 18:36, lofyer 写道: > 于 2013/5/26 15:41, Itamar Heim 写道: >> On 05/26/2013 09:59 AM, Roy Golan wrote: >>> On 05/24/2013 03:22 PM, Itamar Heim wrote: >>>> On 05/23/2013 04:23 PM, lofyer wrote: >>>>> Can host hooks be used to implement the following policy to avoid >>>>> "boot >>>>> storm"? >>>>> >>>>> 1.count and sort VMs awaiting for boot. >>>>> 2.If the count is less than or equal to, for example 5, then boot all >>>>> VMs and exit the script. >>>>> 3.Otherwise, boot and dequeue vm0 to vm4, and minus the count by 5. >>>>> 4.Sleep some time, and go to step 2. >>>>> _______________________________________________ >>>>> Users mailing list >>>>> Users(a)ovirt.org >>>>> http://lists.ovirt.org/mailman/listinfo/users >>>> >>>> hooks run one on vm-start one by one. would be a bit tricky to do the >>>> above. >>>> roy - didn't you add some mechanism to throttle boot storms in the >>>> engine? >>> yes at RunVmCommandBase.delay(Guid vdsId) - but it doesn't fit here. >>> It'll delay the VM run only when there is no free memory to run the VM >>> and will wait till engine signals after gathering statistics of >>> powering up VMs. >> >> lofyer - any other issue other than memory bottleneck you were trying >> to resolve? >> >> Thanks, >> Itamar > I think only cpu_load here. If I start 8 VMs(1G memory each) in a 16G > host, it will be very slow for VMs to enter the desktop mode from the > time I click "start". > At first I thought it would be a resolution if I put these boot > processes into a linear squence or delay a random period by using hooks. > Is there an option that I can choose to arrange the boot squence in > the engine? > However, since each VM takes quite a long time to startup, there is no > need to do that. Just plug in more CPUs...... Knowing that some other factors will affect it, can I use an SSD as a "boot cache"?