Ubuntu
linux package

  1. Bug #1792102
  2. Comment #0

Comment 0 for bug 1792102

Revision history for this message
bugproxy (bugproxy) wrote :

== Comment: #0 - Michael Ranweiler <email address hidden> - 2018-09-10 19:26:14 ==

Due to a recent change for powernv, now the total GPU memory is no longer available. This impacts performance for any application/benchmark has a large GPU memory utilization.

Previous amount of memory : 16128MiB
Current amount of available memory : 15360MiB

From Anton, describing the recent change.:
   powerpc/powernv: Increase memory block size to 1GB on radix

  Memory hot unplug on PowerNV radix hosts is broken. Our memory block
  size is 256MB but since we map the linear region with very large
  pages, each pte we tear down maps 1GB.

  A hot unplug of one 256MB memory block results in 768MB of memory
  getting unintentionally unmapped. At this point we are likely to oops.

  Fix this by increasing our memory block size to 1GB on PowerNV radix
  hosts.

  Fixes: 4b5d62ca17a1 ("powerpc/mm: add radix__remove_section_mapping()")

This is fixed with:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7acf50e4efa6