← Back to team overview

documentation-packages team mailing list archive

[Bug 1666286] Re: Memory hot plug: increase the number of slots from '32' to '256' (Documentation)


Well, there is this section in the official server guide:


I changed this report to the server guide project, so the maintainers of
that guide can consider your suggestion. Thanks!

** Package changed: ubuntu-docs (Ubuntu) => serverguide

** Changed in: serverguide
       Status: Incomplete => New

You received this bug notification because you are a member of
Documentation Packages, which is subscribed to ubuntu-docs in Ubuntu.

  Memory hot plug: increase the number of slots from '32' to '256'

Status in Ubuntu Server Guide:

Bug description:
  IBM would like to have the following documented wherever appropriate:

  ---Problem Description---
  In Ubuntu 17.04, when trying to increase the number of memory slots from 32 to 256, only 63 slots were available even though 256 slots was specified in the guest xml.

  Machine Type = POWER8

  Even though 256 slots are supported in QEMU 2.8, distributed with
  Ubuntu 17.04, there is an implicit limit coming from the vhost
  backend, limiting the  number of max memory slots that are supported.

  The work around is to increase the vhost mem slots by reloading the
  vhost module in the guest:

  [root@localhost ~]# modprobe -r vhost
  [root@localhost ~]# modprobe vhost max_mem_regions=512
  [root@localhost ~]# cat /sys/module/vhost/parameters/max_mem_regions

To manage notifications about this bug go to: