linux - 将linux内存设置为unlimit会产生不利影响吗？

Question

我在 Linux 服务器上运行 MPI 作业。我得到错误:

--------------------------------------------------------------------------
The OpenFabrics (openib) BTL failed to initialize while trying to
allocate some locked memory.  This typically can indicate that the
memlock limits are set too low.  For most HPC installations, the
memlock limits should be set to "unlimited".  The failure occured
here:

Local host:    yw0431
OMPI source:   ../../../../../ompi/mca/btl/openib/btl_openib_component.c:1216
Function:      ompi_free_list_init_ex_new()
Device:        mlx4_0
Memlock limit: 65536

You may need to consult with your system administrator to get this
problem fixed.  This FAQ entry on the Open MPI web site may also be
helpful:

 http://www.open-mpi.org/faq/?category=openfabrics#ib-locked-pages 
 --------------------------------------------------------------------------
 --------------------------------------------------------------------------
WARNING: There was an error initializing an OpenFabrics device.

Local host:   yw0431
Local device: mlx4_0
--------------------------------------------------------------------------
[yw0431:20193] 11 more processes have sent help message help-mpi-btl-openib.txt / init-fail-no-mem
[yw0431:20193] Set MCA parameter "orte_base_help_aggregate" to 0 to see all help / error messages
[yw0431:20193] 11 more processes have sent help message help-mpi-btl-openib.txt / error in device init
 forrtl: error (78): process killed (SIGTERM)

这意味着我的 linux 服务器已将内存锁定为 65M，但我的工作需要更多内存。我觉得2G应该够了。

我找到了一个关于 ulimiting 内存的解决方案:

 ulimit -l unlimited

但我担心我会导致系统崩溃或发生一些不好的事情。

那么我可以设置“ulimit -l umlimited”吗？

Answer 1

当您将 ulimit 设置为无限制并且您的进程开始耗尽内存时，OOM killer 将终止您的系统稳定性工作，我会将 ulimit 设置为 RAM 的 80% 到 90%，而不是无限制。