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https://issues.apache.org/jira/browse/MESOS-1791?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14145449#comment-14145449
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Adam B commented on MESOS-1791:
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Preemption (or at least inverse offers) would certainly help in the case where
there are not enough available resources to satisfy a new reservation, but the
reservations could also be seen as a desired state to try to reach once tasks
complete and enough resources become available to reallocate to the new
role/framework.
A few definitions/clarifications:
"Master reservations" are a way for the master to provide centralized control
over the reservations on every slave. These may be the same static role-based
reservations, except they are configurable through the master, perhaps as an
(authenticated) web/REST interface. It could be as simple as the same
reservation info forwarded to all slaves ("reserve 1GB RAM on every slave"), or
configurable per-slave.
"Offer reservations" are not tied to particular slaves, but allow a framework
to request a certain amount of global resources (perhaps split into multiple
sets, one per host), regardless of placement. An example would be "make sure my
framework/role always has 20cpus and 20GB RAM available somewhere in the
cluster, but I don't care where." In this scenario, slaves do not need to
specifically reserve any of their resources for that framework, so long as the
offer reservation can be satisfied by resources from the rest of the cluster.
The master will be responsible for enforcing these reservations. The
framework/role gets the benefit of defining its desired resources at a higher
level of abstraction, without knowledge of how many machines there are or how
much resources are available on each.
> Introduce Master / Offer Resource Reservations
> ----------------------------------------------
>
> Key: MESOS-1791
> URL: https://issues.apache.org/jira/browse/MESOS-1791
> Project: Mesos
> Issue Type: Epic
> Reporter: Tom Arnfeld
>
> Currently Mesos supports the ability to reserve resources (for a given role)
> on a per-slave basis, as introduced in MESOS-505. This allows you to almost
> statically partition off a set of resources on a set of machines, to
> guarantee certain types of frameworks get some resources.
> This is very useful, though it is also very useful to be able to control
> these reservations through the master (instead of per-slave) for when I don't
> care which nodes I get on, as long as I get X cpu and Y RAM, or Z sets of
> (X,Y).
> I'm not sure what structure this could take, but apparently it has already
> been discussed. Would this be a CLI flag? Could there be a (authenticated)
> web interface to control these reservations?
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