> On June 22, 2015, 1:32 p.m., Alexander Rukletsov wrote: > > src/master/master.cpp, line 749 > > <https://reviews.apache.org/r/35702/diff/6/?file=989449#file989449line749> > > > > I think reserve is too abstract and may collide with future actions > > (think quota). How about `/dynamic/reserve`? > > Alexander Rukletsov wrote: > Though we currently do not support slashes in endpoints, I think we > should fix that first before introducing a `/reserve` endpoint, given these > endpoint are not targeted for 0.23. > > Joris Van Remoortere wrote: > Cody had some patches for enabling sub namespaces in endpoints (as in > enabling slashes). Might be worth pulling those in. > > Alexander Rukletsov wrote: > Yep, it's https://issues.apache.org/jira/browse/MESOS-2130, I plan to > bring up the discussion today at the community sync. > > Michael Park wrote: > The concensus for now seems that (1) we introduce the allocator changes, > but address the allocator refactor sooner rather than later, (2) go with > `/reserve` for now and update them once the HTTP API folks get to supporting > the nested endpoint stuff.
And (3) we update endpoints names before the following release, i.e. there is no Mesos release, where `/reserve` will exist. Correct? - Alexander ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/35702/#review88781 ----------------------------------------------------------- On July 27, 2015, 11:30 p.m., Michael Park wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/35702/ > ----------------------------------------------------------- > > (Updated July 27, 2015, 11:30 p.m.) > > > Review request for mesos, Adam B, Benjamin Hindman, Ben Mahler, Jie Yu, Joris > Van Remoortere, and Vinod Kone. > > > Bugs: MESOS-2600 > https://issues.apache.org/jira/browse/MESOS-2600 > > > Repository: mesos > > > Description > ------- > > This involved a lot more challenges than I anticipated, I've captured the > various approaches and limitations and deal-breakers of those approaches > here: [Master Endpoint Implementation > Challenges](https://docs.google.com/document/d/1cwVz4aKiCYP9Y4MOwHYZkyaiuEv7fArCye-vPvB2lAI/edit#) > > Key points: > > * This is a stop-gap solution until we shift the offer creation/management > logic from the master to the allocator. > * `updateAvailable` and `updateSlave` are kept separate because > (1) `updateAvailable` is allowed to fail whereas `updateSlave` must not. > (2) `updateAvailable` returns a `Future` whereas `updateSlave` does not. > (3) `updateAvailable` never leaves the allocator in an over-allocated state > and must not, whereas `updateSlave` does, and can. > * The algorithm: > * Initially, the master pessimistically assume that what seems like > "available" resources will be gone. > This is due to the race between the allocator scheduling an `allocate` > call to itself vs master's `allocator->updateAvailable` invocation. > As such, we first try to satisfy the request only with the offered > resources. > * We greedily rescind one offer at a time until we've rescinded > sufficiently many offers. > IMPORTANT: We perform `recoverResources(..., Filters())` rather than > `recoverResources(..., None())` so that we can pretty much always win the > race against `allocate`. > In the case that we lose, no disaster occurs. We simply fail > to satisfy the request. > * If we still don't have enough resources after resciding all offers, be > optimistic and forward the request to the allocator since there may be > available resources to satisfy the request. > * If the allocator returns a failure, report the error to the user with > `PreconditionFailed`. This could be updated to be `Forbidden`, or `Conflict` > maybe as well. We'll pick one eventually. > > This approach is clearly not ideal, since we would prefer to rescind as > little offers as possible. > The challenges of implementing the ideal solution in the current state is > described in the document above. > > TODO(mpark): Add more comments and test cases. > > > Diffs > ----- > > src/master/http.cpp 3a1598fad4db03e5f62fd4a6bd26b2bedeee4070 > src/master/master.hpp 827d0d599912b2936beb9615610f627f6c9a2d43 > src/master/master.cpp 5b5e3c37d4433c8524db267866aebc0a35a181f1 > src/master/validation.hpp 469d6f56c3de28a34177124aae81ce24cb4ad160 > src/master/validation.cpp 9d128aa1b349b018b8e4a1916434d848761ca051 > > Diff: https://reviews.apache.org/r/35702/diff/ > > > Testing > ------- > > `make check` > > > Thanks, > > Michael Park > >
