| 2014-07-22 13:48:54 |
Chris J Arges |
bug |
|
|
added bug |
| 2014-07-22 13:49:06 |
Chris J Arges |
description |
[Impact]
When using KVM on NUMA machines, both Linux and Windows guests can exhibit very poor performance and potential crashes. Disabling KSM is a known workaround to fix this issue.
[ Fix ]
The following patch fixes the issue in our testing:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=64a9a34e22896dad430e21a28ad8cb00a756fefc
This patch is present in v3.14-rc1 and onwards.
[Test Case]
General test case:
1) On a NUMA capable machine, setup the machine as a KVM hypervisor
- lscpu should show more than 1 NUMA node
2) Install 4 KVM VMs
3) Run the following in another terminal to ensure that pages_shared and pages_sharing is increasing
- watch 'tail /sys/kernel/mm/ksm/*'
4) In another terminal run a program that continually pings each node and alerts on high latencies
What we've observed is that in Linux guests, the ping latencies can go into the ~2 second range for a few pings, then return back to the < 1ms range. (This is machine dependent.) In addition, using Windows guests, occasionally when running this test we observe that the guests BSOD during this test. |
[Impact]
When using KVM on NUMA machines, both Linux and Windows guests can exhibit very poor performance and potential crashes. Disabling KSM is a known workaround to fix this issue.
[Fix]
The following patch fixes the issue in our testing:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=64a9a34e22896dad430e21a28ad8cb00a756fefc
This patch is present in v3.14-rc1 and onwards.
[Test Case]
General test case:
1) On a NUMA capable machine, setup the machine as a KVM hypervisor
- lscpu should show more than 1 NUMA node
2) Install 4 KVM VMs
3) Run the following in another terminal to ensure that pages_shared and pages_sharing is increasing
- watch 'tail /sys/kernel/mm/ksm/*'
4) In another terminal run a program that continually pings each node and alerts on high latencies
What we've observed is that in Linux guests, the ping latencies can go into the ~2 second range for a few pings, then return back to the < 1ms range. (This is machine dependent.) In addition, using Windows guests, occasionally when running this test we observe that the guests BSOD during this test. |
|
| 2014-07-22 13:49:12 |
Chris J Arges |
nominated for series |
|
Ubuntu Trusty |
|
| 2014-07-22 13:49:12 |
Chris J Arges |
bug task added |
|
linux (Ubuntu Trusty) |
|
| 2014-07-22 13:49:18 |
Chris J Arges |
linux (Ubuntu Trusty): assignee |
|
Chris J Arges (arges) |
|
| 2014-07-22 13:49:20 |
Chris J Arges |
linux (Ubuntu): assignee |
Chris J Arges (arges) |
|
|
| 2014-07-22 13:49:22 |
Chris J Arges |
linux (Ubuntu Trusty): importance |
Undecided |
High |
|
| 2014-07-22 13:49:24 |
Chris J Arges |
linux (Ubuntu Trusty): status |
New |
In Progress |
|
| 2014-07-22 13:49:26 |
Chris J Arges |
linux (Ubuntu): status |
In Progress |
Fix Released |
|
| 2014-07-22 13:49:28 |
Chris J Arges |
linux (Ubuntu): importance |
High |
Undecided |
|
| 2014-07-22 13:51:29 |
Chris J Arges |
description |
[Impact]
When using KVM on NUMA machines, both Linux and Windows guests can exhibit very poor performance and potential crashes. Disabling KSM is a known workaround to fix this issue.
[Fix]
The following patch fixes the issue in our testing:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=64a9a34e22896dad430e21a28ad8cb00a756fefc
This patch is present in v3.14-rc1 and onwards.
[Test Case]
General test case:
1) On a NUMA capable machine, setup the machine as a KVM hypervisor
- lscpu should show more than 1 NUMA node
2) Install 4 KVM VMs
3) Run the following in another terminal to ensure that pages_shared and pages_sharing is increasing
- watch 'tail /sys/kernel/mm/ksm/*'
4) In another terminal run a program that continually pings each node and alerts on high latencies
What we've observed is that in Linux guests, the ping latencies can go into the ~2 second range for a few pings, then return back to the < 1ms range. (This is machine dependent.) In addition, using Windows guests, occasionally when running this test we observe that the guests BSOD during this test. |
[Impact]
When using KVM on NUMA machines, both Linux and Windows guests can exhibit very poor performance and potential crashes. Disabling KSM is a known workaround to fix this issue.
[Fix]
The following patch fixes the issue in our testing:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=64a9a34e22896dad430e21a28ad8cb00a756fefc
This patch is present in v3.14-rc1 and onwards.
[Test Case]
General test case:
1) On a NUMA capable machine, setup the machine as a KVM hypervisor
- lscpu should show more than 1 NUMA node
2) Install 4 KVM VMs
3) Run the following in another terminal to ensure that pages_shared and pages_sharing is increasing
- watch 'tail /sys/kernel/mm/ksm/*'
4) In another terminal run a program that continually pings each node and alerts on high latencies
What we've observed is that in Linux guests, the ping latencies can go into the ~2 second range for a few pings, then return back to the < 1ms range. (This is machine dependent.) In addition, occasionally when running this test with Windows guests we observe BSODs during this test. |
|
| 2014-07-22 15:08:15 |
Nobuto Murata |
bug |
|
|
added subscriber Nobuto MURATA |
| 2014-07-22 17:17:32 |
cjs |
bug |
|
|
added subscriber cjs |
| 2014-07-22 18:08:50 |
Joseph Salisbury |
linux (Ubuntu): importance |
Undecided |
High |
|
| 2014-07-22 18:21:19 |
Jan Henke |
bug |
|
|
added subscriber Jan Henke |
| 2014-07-22 18:51:11 |
Tim Gardner |
bug |
|
|
added subscriber Tim Gardner |
| 2014-07-22 20:32:41 |
Peter Matulis |
bug |
|
|
added subscriber Canonical Support |
| 2014-07-23 20:30:03 |
Jeff Wilson |
bug |
|
|
added subscriber Jeff Wilson |
| 2014-07-24 14:49:20 |
Mike Lowe |
bug |
|
|
added subscriber Mike Lowe |
| 2014-07-24 16:06:46 |
Steve |
bug |
|
|
added subscriber Steve |
| 2014-07-24 22:29:26 |
Tim Gardner |
linux (Ubuntu Trusty): status |
In Progress |
Fix Committed |
|
| 2014-07-24 23:06:01 |
Mohammed Naser |
bug |
|
|
added subscriber Mohammed Naser |
| 2014-07-25 06:48:34 |
Ilya Almametov |
bug |
|
|
added subscriber Ilya Almametov |
| 2014-08-04 22:19:44 |
Andreas Ntaflos |
bug |
|
|
added subscriber Andreas Ntaflos |
| 2014-08-05 04:12:05 |
David Miller |
bug |
|
|
added subscriber David Miller |
| 2014-08-05 22:02:44 |
Jennifer Mehl |
bug |
|
|
added subscriber Jennifer Mehl |
| 2014-08-08 22:44:42 |
Launchpad Janitor |
branch linked |
|
lp:ubuntu/precise-proposed/linux-lts-trusty |
|
| 2014-08-11 23:33:34 |
Launchpad Janitor |
linux (Ubuntu Trusty): status |
Fix Committed |
Fix Released |
|
| 2014-08-11 23:50:43 |
Launchpad Janitor |
branch linked |
|
lp:ubuntu/precise-security/linux-lts-trusty |
|
| 2014-08-21 12:59:14 |
scottcargill@gmail.com |
bug |
|
|
added subscriber scottcargill@gmail.com |
| 2014-09-12 07:46:11 |
Dr. Jens Harbott |
bug |
|
|
added subscriber Dr. Jens Rosenboom |
| 2014-12-11 12:44:46 |
Lincoln Stoll |
bug |
|
|
added subscriber Lincoln Stoll |
| 2014-12-26 06:09:47 |
Jerome Deyle |
bug |
|
|
added subscriber Jerome Deyle |
| 2015-03-23 15:12:49 |
scottcargill@gmail.com |
removed subscriber scottcargill@gmail.com |
|
|
|
| 2015-06-25 08:00:11 |
Quest Ion |
bug |
|
|
added subscriber Quest Ion |
| 2015-08-17 13:04:24 |
Vasiliy |
bug |
|
|
added subscriber Vasiliy |
| 2015-09-16 10:28:04 |
Dominic Marks |
bug |
|
|
added subscriber Dominic Marks |
| 2016-01-28 04:43:56 |
Allen Gao |
bug |
|
|
added subscriber Allen Gao |
| 2016-12-09 07:06:28 |
to-hiro |
linux (Ubuntu Trusty): milestone |
|
trusty-updates |
|
| 2016-12-09 17:48:51 |
Jennifer Mehl |
removed subscriber Jennifer Mehl |
|
|
|
| 2019-02-06 02:58:38 |
Jan Henke |
removed subscriber Jan Henke |
|
|
|
| 2019-02-06 12:59:01 |
Mauricio Faria de Oliveira |
bug |
|
|
added subscriber Mauricio Faria de Oliveira |
| 2019-07-24 20:55:27 |
Brad Figg |
tags |
|
cscc |
|
