KVM SnowRidge Adaptive PEBS

[Paul Lai]

With the addition of more CPU state information of data, the PEBS(Processor Event Based Sampling) record size is greatly increased. However, most general users of PEBS require just the eventingIP and do not require such a large PEBS record.
 Adaptive PEBS provides Software the capability to configure the PEBS records to capture only the data of interest, keeping the record size compact.
 Need modify KVM and Qemu.

Adaptive PEBS (Processor Event Based Sampling) is configurable PEBS records for only interested data collection from massive PEBS data. It depends on PEBS via PT. The enabling work includes:
◾Expose this feature and MSR configure bit in guest PEBS driver
◾Save and restore status in vCPU when vm_exit and vm_entry
◾Support both host-guest mode and system mode.

Target Kernel: 5.2
Target Release: 19.10

[Christian Ehrhardt  (paelzer)]

Hi,
title says KVM, but the bug is only against xen so far.

Will this need an "qemu (ubuntu)" and/or "linux (ubuntu)" task as well?

- kernel 4.20 is listed so I assume the latter.
- Comment mentions Qemu, will it be in 2.13 or are changes needed on top?

[Christian Ehrhardt  (paelzer)]

Again, this semes to be a Kernel/qemu bug that was only filed against xen.
Added bug tasks to not get lost.

[Christian Ehrhardt  (paelzer)]

Are there updates and/or references to commits in those projects already that we can use to track and integrate those features?

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 1782208

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Christian Ehrhardt  (paelzer)]

Feature request that does not need the kernel logs the bot asks for

[Paul Lai (pclai)]

No updates/upstream at this time.

-----Original Message-----
From: <email address hidden> [mailto:<email address hidden>] On Behalf Of Christian Ehrhardt ?
Sent: Monday, May 6, 2019 10:29 PM
To: Lai, Paul C <email address hidden>
Subject: [Bug 1782208] Re: KVM SnowRidge Adaptive PEBS

Are there updates and/or references to commits in those projects already that we can use to track and integrate those features?

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https://bugs.launchpad.net/bugs/1782208

Title:
  KVM SnowRidge Adaptive PEBS

Status in linux package in Ubuntu:
  Incomplete
Status in qemu package in Ubuntu:
  New
Status in xen package in Ubuntu:
  New

Bug description:
  With the addition of more CPU state information of data, the PEBS(Processor Event Based Sampling) record size is greatly increased. However, most general users of PEBS require just the eventingIP and do not require such a large PEBS record.
   Adaptive PEBS provides Software the capability to configure the PEBS records to capture only the data of interest, keeping the record size compact.
   Need modify KVM and Qemu.

  Adaptive PEBS (Processor Event Based Sampling) is configurable PEBS records for only interested data collection from massive PEBS data. It depends on PEBS via PT. The enabling work includes:
  ◾Expose this feature and MSR configure bit in guest PEBS driver
  ◾Save and restore status in vCPU when vm_exit and vm_entry
  ◾Support both host-guest mode and system mode.

  Target Kernel: 5.2
  Target Release: 19.10

To manage notifications about this bug go to:
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