mesos-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Vinod Kone" <vinodk...@gmail.com>
Subject Re: Review Request 25035: Fix for MESOS-1688
Date Mon, 15 Sep 2014 17:26:05 GMT


> On Sept. 15, 2014, 3:23 p.m., Timothy St. Clair wrote:
> > src/master/hierarchical_allocator_process.hpp, line 837
> > <https://reviews.apache.org/r/25035/diff/7/?file=688721#file688721line837>
> >
> >     What happens in the case where all CPUs are taken but memory is available? 
It looks like it will return (true), but this should not be possible. 
> >     
> >     I think you want to give an offer in the case where there are CPU resources
available, but memory is consumed by the executor.

Giving memory only resources is ok as long as it is used for a task and not an executor. See
my comments above.


- Vinod


-----------------------------------------------------------
This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/25035/#review53343
-----------------------------------------------------------


On Sept. 13, 2014, 7:10 p.m., Martin Weindel wrote:
> 
> -----------------------------------------------------------
> This is an automatically generated e-mail. To reply, visit:
> https://reviews.apache.org/r/25035/
> -----------------------------------------------------------
> 
> (Updated Sept. 13, 2014, 7:10 p.m.)
> 
> 
> Review request for mesos and Vinod Kone.
> 
> 
> Bugs: MESOS-1688
>     https://issues.apache.org/jira/browse/MESOS-1688
> 
> 
> Repository: mesos-git
> 
> 
> Description
> -------
> 
> As already explained in JIRA MESOS-1688, there are schedulers allocating memory only
for the executor and not for tasks. For tasks only CPU resources are allocated in this case.
> Such a scheduler does not get offered any idle CPUs if the slave has nearly used up all
memory.
> This can easily lead to a dead lock (in the application, not in Mesos).
> 
> Simple example:
> 1. Scheduler allocates all memory of a slave for an executor
> 2. Scheduler launches a task for this executor (allocating 1 CPU)
> 3. Task finishes: 1 CPU , 0 MB memory allocatable.
> 4. No offers are made, as no memory is left. Scheduler will wait for offers forever.
Dead lock in the application.
> 
> To fix this problem, offers must be made if CPU resources are allocatable without considering
allocatable memory
> 
> 
> Diffs
> -----
> 
>   CHANGELOG a822cc4 
>   src/common/resources.cpp edf36b1 
>   src/master/constants.cpp faa1503 
>   src/master/hierarchical_allocator_process.hpp 34f8cd6 
>   src/master/master.cpp 18464ba 
>   src/tests/allocator_tests.cpp 774528a 
> 
> Diff: https://reviews.apache.org/r/25035/diff/
> 
> 
> Testing
> -------
> 
> Deployed patched Mesos 0.19.1 on a small cluster with 3 slaves and tested running multiple
parallel Spark jobs in "fine-grained" mode to saturate allocatable memory. The jobs run fine
now. This load always caused a dead lock in all Spark jobs within one minute with the unpatched
Mesos.
> 
> 
> Thanks,
> 
> Martin Weindel
> 
>


Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message