fuel-dev team mailing list archive

[Roman Sokolkov <rsokolkov@xxxxxxxxxxxx>]

Just small update about overcommit ratios

As recommended by Red
Hat<https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/5/html/Virtualization/sect-Virtualization-Tips_and_tricks-Overcommitting_with_KVM.html>
vCPU/CPU (cpu_allocation_ratio) = 5 (default 16)
vRAM/RAM (ram_allocation_ratio) = 1.5

Thanks.



On Fri, Apr 4, 2014 at 1:04 PM, Roman Sokolkov <rsokolkov@xxxxxxxxxxxx>wrote:

> Folks,
>
> Any updates on that?
> Customers that run Fuel for production exactly need finely tuned scheduler.
> My two latest projects were affected by default "RAW" scheduling.
>
> Thank you.
>
>
> On Fri, Mar 21, 2014 at 7:18 AM, Bogdan Dobrelya <bdobrelia@xxxxxxxxxxxx>wrote:
>
>> On 03/21/2014 03:04 PM, Dmitry Ukov wrote:
>> > Core and Disk  filters should be enabled (they are disabled by default)
>> > in order to avoid compute node oveloading
>> > - cpu_allocation_ratio=1.0 - was customer requirement. I think 16.0 is
>> > way to big over commit ratio (potentially 16 vms on 1 core). I would say
>> > 2.0 or 3.0 will be reasonable here.
>> > - disk_allocation_ratio=1.0 - it is unsafe to over commit disk
>> > - ram_allocation_ratio=1.0 - this was customer requirement. Actually we
>> > can use default value here. (AFAIR default is 1.5 )
>> > - ram_weight_multiplier=0.0 and scheduler_host_subset_size=30 will help
>> > us to get random VMs distribution if compute nodes significantly differ
>> > from each other in terms of total RAM amount
>>
>> Thank you, that makes sense. I vote for enable these ones (leaving the
>> ram_allocation_ratio defaults) for Fuel nova manifests for Puppet. That
>> do you think?
>>
>> >
>> >
>> >
>> > On Thu, Mar 20, 2014 at 2:58 PM, Bogdan Dobrelya <
>> bdobrelia@xxxxxxxxxxxx
>> > <mailto:bdobrelia@xxxxxxxxxxxx>> wrote:
>> >
>> >     On 03/20/2014 08:47 AM, Mike Scherbakov wrote:
>> >     > Hi Dmitry,
>> >     > I was running through bp created by
>> >     > you:
>> >
>> https://blueprints.launchpad.net/fuel/+spec/scheduler-config-improvements
>> .
>> >     >
>> >
>> >     Interesting, why CPU overcommitment defaults (
>> >
>> https://github.com/openstack/nova/blob/master/etc/nova/nova.conf.sample#L1759
>> >     ) are so 'bad' to being changed so drastically 16->1?
>> >
>> >     > I'm wondering whether this config will work fine for every
>> >     installation
>> >     > we do with Fuel.. what are the possible limitations / corner
>> cases?
>> >     >
>> >     > Thanks,
>> >     > --
>> >     > Mike Scherbakov
>> >     > #mihgen
>> >     >
>> >     >
>> >
>> >
>> >     --
>> >     Best regards,
>> >     Bogdan Dobrelya,
>> >     Skype #bogdando_at_yahoo.com <http://bogdando_at_yahoo.com>
>> >     Irc #bogdando
>> >
>> >
>> >
>> >
>> > --
>> > Kind regards
>> > Dmitry Ukov
>> > IT Engineer
>> > Mirantis, Inc.
>> >
>>
>>
>> --
>> Best regards,
>> Bogdan Dobrelya,
>> Skype #bogdando_at_yahoo.com
>> Irc #bogdando
>>
>> --
>> Mailing list: https://launchpad.net/~fuel-dev
>> Post to     : fuel-dev@xxxxxxxxxxxxxxxxxxx
>> Unsubscribe : https://launchpad.net/~fuel-dev
>> More help   : https://help.launchpad.net/ListHelp
>>
>
>
>
> --
> Roman Sokolkov,
> Deployment Engineer,
> Mirantis, Inc.
> Skype rsokolkov,
> rsokolkov@xxxxxxxxxxxx
>



-- 
Roman Sokolkov,
Deployment Engineer,
Mirantis, Inc.
Skype rsokolkov,
rsokolkov@xxxxxxxxxxxx