Kernel trace buffer should be cleared and size restored after profiling
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
ureadahead (Ubuntu) |
Fix Released
|
High
|
Unassigned | ||
Lucid |
Fix Released
|
High
|
Tim Gardner | ||
Maverick |
Fix Released
|
High
|
Unassigned |
Bug Description
Binary package hint: ureadahead
After removing /var/lib/
initially free would report:
-----------------
Wed Dec 30 12:26:32 CST 2009
total used free shared buffers cached
Mem: 1021932 290380 731552 0 27260 106168
-/+ buffers/cache: 156952 864980
Swap: 329292 0 329292
-----------------
Then after removing the pack file and rebooting free would report:
-----------------
Wed Dec 30 12:27:24 CST 2009
total used free shared buffers cached
Mem: 1021932 419912 602020 0 18628 105924
-/+ buffers/cache: 295360 726572
Swap: 329292 0 329292
I also occasionally received a segfault message at this step, but not every time:
------------------
Dec 30 12:27:10 lucid-test kernel: [ 21.683656] Xorg[1218]: segfault at 0 ip 00007f742252ce1b sp 00007fffaf8b0468 error 4 in libc-2.
------------------
After next reboot:
-----------------
Wed Dec 30 12:30:46 CST 2009
total used free shared buffers cached
Mem: 1021932 302296 719636 0 33304 112048
-/+ buffers/cache: 156944 864988
Swap: 329292 0 329292
-----------------
I initially discovered this after updating my headless server from jaunty to karmic and noticed the green memory bar in htop was much larger than normal.
There is more information on the forums: http://
ProblemType: Bug
Architecture: amd64
Date: Wed Dec 30 12:55:58 2009
DistroRelease: Ubuntu 10.04
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Alpha amd64 (20091215.1)
PackDump: Error: command ['ureadahead', '--dump'] failed with exit code 4: ureadahead:
Package: ureadahead 0.100.0-3
ProcEnviron:
LANG=en_US.UTF-8
SHELL=/bin/bash
ProcVersionSign
SourcePackage: ureadahead
Tags: lucid
Uname: Linux 2.6.32-9-generic x86_64
Related branches
Changed in ureadahead (Ubuntu): | |
status: | New → Confirmed |
summary: |
- ureadahead doesn't reduce tracing buffer after profile + Kernel trace buffer should be cleared and size restored after profiling |
Changed in ureadahead (Ubuntu): | |
importance: | Medium → High |
tags: |
added: verification-done removed: verification-needed |
Changed in ureadahead (Ubuntu Lucid): | |
assignee: | Tim Gardner (timg-tpi) → arturm (arturm) |
Changed in ureadahead (Ubuntu Lucid): | |
assignee: | arturm (arturm) → Tim Gardner (timg-tpi) |
tags: | added: hwe-blocker |
Same issue here with normal up-to-date Karmic.
I was trying to trigger a re-profiling and ran
ureadahead --force-trace
The memory usage increased immediately and was never released. I only realized afterwards that this wasn't the good approach for doing what I wanted, and removed merely the pack. After next reboot, memory was high, get never free'd after some time but another reboot later all was normal.
It seems I've understood why sometimes a huge amount of my 1Go memory was eaten... the strange thing is this memory doesn't show in any monitor like top etc.