I would like to add that you may want to play with the value and see what works for your applications. Most applications should be using malloc or similar functions to allocate large memory regions in the heap and not on the stack.
-Nathan On Mon, Sep 28, 2015 at 08:01:09PM +0300, Mike Dubman wrote: > Hello Grigory, > We observed ~10% performance degradation with heap size set to unlimited > for CFD applications. > You can measure your application performance with default and unlimited > "limits" and select the best setting. > Kind Regards. > M > On Mon, Sep 28, 2015 at 7:36 PM, Grigory Shamov > <grigory.sha...@umanitoba.ca> wrote: > > Hi All, > > We have built OpenMPI (1.8.8., 1.10.0) against Mellanox OFED 2.4 and > corresponding MXM. When it runs now, it gives the following warning, per > process: > > [1443457390.911053] [myhist:5891 :0] mxm.c:185 MXM WARN The > 'ulimit -s' on the system is set to 'unlimited'. This may have negative > performance implications. Please set the heap size to the default value > (10240) > > We have ulimits for heap (as well as most of the other limits) set > unlimited because of applications that might possibly need a lot of RAM. > > The question is if we should do as MXM wants, or ignore it? Has anyone > an > experience running recent OpenMPI with MXM enabled, and what kind of > ulimits do you have? Any suggestions/comments appreciated, thanks! > > -- > Grigory Shamov > > Westgrid/ComputeCanada Site Lead > University of Manitoba > E2-588 EITC Building, > (204) 474-9625 > > _______________________________________________ > users mailing list > us...@open-mpi.org > Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/users > Link to this post: > http://www.open-mpi.org/community/lists/users/2015/09/27697.php > > -- > Kind Regards, > M. > _______________________________________________ > users mailing list > us...@open-mpi.org > Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/users > Link to this post: > http://www.open-mpi.org/community/lists/users/2015/09/27698.php
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