Re: Review Request 70132: Do not implicitly decline speculatively converted resources.

[Chun-Hung Hsiao <ch...@apache.org>]

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This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/70132/
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(Updated May 1, 2019, 8:35 p.m.)


Review request for mesos, Benjamin Bannier, Benjamin Mahler, and Meng Zhu.


Changes
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Addressed BenM's comments.


Bugs: MESOS-9616
    https://issues.apache.org/jira/browse/MESOS-9616


Repository: mesos


Description (updated)
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Currently if a framework accepts an offer with a `RESERVE` operation
without a task consuming the reserved resources, the resources will be
implicitly declined. This is counter to what one would expect (that only
the remaining resources in the offer will be declined):

  Offer `cpus:10` -> `ACCEPT` with `RESERVE cpus(role):1`
                     *Actual* implicit decline: `cpus:9;cpus(role):1`
                     *Expected* implicit decline: `cpus:9`

The same issue is present with other transformational operations (i.e.,
`UNRESERVE`, `CREATE` and `DESTROY`).

This patch fixes this issue by only implicitly declining the "remaining"
untransformed resources, computed as follows:

  Offered = `cpus:10`
  Remaining = `cpus:9;cpus(role):1`
  Implicitly declined = remaining - (remaining - offered)
                      = `cpus:9;cpus(role):1` - `cpus:(role):1`
                      = `cpus:9`


Diffs (updated)
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  src/master/master.cpp ad54ae217863a08f4e6d743b39c176b171353084 
  src/tests/slave_tests.cpp b1c3a01031b917fb9773c8c890a8f88838870559 


Diff: https://reviews.apache.org/r/70132/diff/8/

Changes: https://reviews.apache.org/r/70132/diff/7-8/


Testing
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make check

More testing done in r/70537.


Thanks,

Chun-Hung Hsiao