Hi!
I'd still like to have "static" utilization as well for the following reasons:
You define a pool of (static) resources (in the sense of utilization capacities) for the nodes. These should be the initial values.
You define (static) resources (in the sense of utilization demands) for your cluster resources (here meaning the services the cluster manages).
The advantage of static values is this: If a system requires more and more resources over time (hopefully up to some limit), the initial placement of resources on the nodes will meet their maximum requirement (if configured correctly).
In the dynamic case, a resource might be placed on a node with insufficient capacities, causing unnecessary migrations if it turn out that the nodes capacities are running low.
I also can imagine that dynamic capacities (avoiding the word "utilization" here) can cause a kind of deadlock; did you consider that?
Regards,
Ulrich Windl
>>> "Xin Wei Hu" <xwhu@novell.com> schrieb am 15.07.2011 um 09:10 in Nachricht
<4E20748C020000C700023D0C@novprvlin0050.provo.novell.com>:
> Hi all,
>
> This is actually about the possible next step about utilization based
> resource allocation in pacemaker. As we know, current pacemaker has the
> ability to do resource allocation based on the utilization of nodes and
> resources. But all these have to be set prior running, and belong to the
> configuration of CIB.
>
> It should be a nature evolution for pacemaker to support dynamic
> utilization based resource reallocation. For that, I'd proposal
> following changes for you to review.
>
> - pacemaker to store the dynamic utilization value in the status
> section of CIB. A changing to the value in configuration triggers a new
> transaction, which is not optimal when trying to update the utilization
> of a pile of resources. Also, by storing it in status, we can leverage
> the attrd_updater with --dempan.
>
> - A new API for RA, for pacemaker to probe the utilization of a
> resource instance. I'd suggest a obvious name, like probe_utilization.
> This new API requires no parameter, and always return $OCF_SUCCESS. RA
> takes the responsibility to update the utilization value when called.
>
>
> _______________________________________________
> ha-wg-technical mailing list
> ha-wg-technical@lists.linux-foundation.org
> https://lists.linux-foundation.org/mailman/listinfo/ha-wg-technical
>
_______________________________________________
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https://lists.linux-foundation.org/mailman/listinfo/ha-wg-technical
I'd still like to have "static" utilization as well for the following reasons:
You define a pool of (static) resources (in the sense of utilization capacities) for the nodes. These should be the initial values.
You define (static) resources (in the sense of utilization demands) for your cluster resources (here meaning the services the cluster manages).
The advantage of static values is this: If a system requires more and more resources over time (hopefully up to some limit), the initial placement of resources on the nodes will meet their maximum requirement (if configured correctly).
In the dynamic case, a resource might be placed on a node with insufficient capacities, causing unnecessary migrations if it turn out that the nodes capacities are running low.
I also can imagine that dynamic capacities (avoiding the word "utilization" here) can cause a kind of deadlock; did you consider that?
Regards,
Ulrich Windl
>>> "Xin Wei Hu" <xwhu@novell.com> schrieb am 15.07.2011 um 09:10 in Nachricht
<4E20748C020000C700023D0C@novprvlin0050.provo.novell.com>:
> Hi all,
>
> This is actually about the possible next step about utilization based
> resource allocation in pacemaker. As we know, current pacemaker has the
> ability to do resource allocation based on the utilization of nodes and
> resources. But all these have to be set prior running, and belong to the
> configuration of CIB.
>
> It should be a nature evolution for pacemaker to support dynamic
> utilization based resource reallocation. For that, I'd proposal
> following changes for you to review.
>
> - pacemaker to store the dynamic utilization value in the status
> section of CIB. A changing to the value in configuration triggers a new
> transaction, which is not optimal when trying to update the utilization
> of a pile of resources. Also, by storing it in status, we can leverage
> the attrd_updater with --dempan.
>
> - A new API for RA, for pacemaker to probe the utilization of a
> resource instance. I'd suggest a obvious name, like probe_utilization.
> This new API requires no parameter, and always return $OCF_SUCCESS. RA
> takes the responsibility to update the utilization value when called.
>
>
> _______________________________________________
> ha-wg-technical mailing list
> ha-wg-technical@lists.linux-foundation.org
> https://lists.linux-foundation.org/mailman/listinfo/ha-wg-technical
>
_______________________________________________
ha-wg-technical mailing list
ha-wg-technical@lists.linux-foundation.org
https://lists.linux-foundation.org/mailman/listinfo/ha-wg-technical