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Bug 1046021 - latencytop not enabled in kernel
Summary: latencytop not enabled in kernel
Keywords:
Status: CLOSED DUPLICATE of bug 1013225
Alias: None
Product: Fedora
Classification: Fedora
Component: kernel
Version: 19
Hardware: Unspecified
OS: Unspecified
unspecified
unspecified
Target Milestone: ---
Assignee: Kernel Maintainer List
QA Contact: Fedora Extras Quality Assurance
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2013-12-23 08:49 UTC by john.haxby@oracle.com
Modified: 2013-12-24 14:19 UTC (History)
5 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2013-12-24 14:19:19 UTC
Type: Bug
Embargoed:

Attachments (Terms of Use)

Description john.haxby@oracle.com 2013-12-23 08:49:31 UTC 
Description of problem:
latencytop reports the following when trying to start it:

  Failed to open /proc/latency_stats: No such file or directory
  Please enable the CONFIG_LATENCYTOP configuration in your kernel.

Version-Release number of selected component (if applicable): kernel-3.12.5-200.fc19.x86_64

How reproducible:
Always.

Steps to Reproduce:
1. Install latencytop.
2. Run latencytop.
3. See latencytop fail.
  
Actual results:
latencytop reports CONFIG_LATENCYTOP not enabled

Expected results:
latencytop starts to measure system latencies.

Additional info:

$ grep CONFIG_LATENCYTOP /boot/config-*
/boot/config-3.11.10-200.fc19.x86_64:# CONFIG_LATENCYTOP is not set
/boot/config-3.11.9-200.fc19.x86_64:# CONFIG_LATENCYTOP is not set
/boot/config-3.12.5-200.fc19.x86_64:# CONFIG_LATENCYTOP is not set
Comment 1 john.haxby@oracle.com 2013-12-23 09:18:02 UTC 
For completeness:

$ grep CONFIG_LATENCYTOP ./boot/config-*
./boot/config-3.12.5-302.fc20.x86_64:# CONFIG_LATENCYTOP is not set
./boot/config-3.13.0-0.rc4.git5.1.fc21.x86_64:# CONFIG_LATENCYTOP is not set

Thse are the current and updatest-testing Fedora 20 kernels.  Feel free to convert this bug to Fedora 20 if it helps.
Comment 2 Josh Boyer 2013-12-24 14:19:19 UTC 
That is a debug option that incurs additional overhead and a performance hit.  It also enables SCHEDSTATS which we currently have disabled because of bug 1013225.

*** This bug has been marked as a duplicate of bug 1013225 ***
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