Enable ftrace function profiler
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Fix Released
|
Wishlist
|
Chase Douglas | ||
Lucid |
Fix Released
|
Wishlist
|
Chase Douglas | ||
Maverick |
Fix Released
|
Wishlist
|
Chase Douglas |
Bug Description
SRU Justification:
Impact: Without function profiling we may have a more difficult time resolving performance issues.
How Addressed: The ftrace function profiler is turned on in the common kernel configs.
Reproduction: No ftrace function profiling is possible on current Ubuntu 10.04 LTS kernel. If it were, the file /sys/kernel/
Regression Potential: Enabling this functionality is an added bonus to Ubuntu that should not cause any regressions. Further, regressions should be localized to the ftrace subsystem, which will not affect the vast majority of users.
=====
The ftrace framework has profiling capabilities that will be useful in
tracking desktop responsiveness. As an example, profiling can tell us
how many times an ISR is run, and how long the average run time is.
This option will not have any performance impact. When turned on at
runtime, a small performance impact may be seen, and a few hundred KB
per cpu of buffer pages will be allocated and used.
Extremely brief overview:
echo 1 > /sys/kernel/
... run tests ...
echo 0 > /sys/kernel/
cat /sys/kernel/
Changed in linux (Ubuntu): | |
status: | In Progress → Fix Committed |
Changed in linux (Ubuntu Lucid): | |
status: | New → Fix Committed |
importance: | Undecided → Wishlist |
Changed in linux (Ubuntu): | |
status: | Fix Committed → In Progress |
Changed in linux (Ubuntu Lucid): | |
assignee: | nobody → Chase Douglas (chasedouglas) |
milestone: | none → lucid-updates |
Changed in linux (Ubuntu): | |
milestone: | lucid-updates → none |
Changed in linux (Ubuntu Maverick): | |
milestone: | none → maverick-alpha-2 |
Accepted linux into lucid-proposed, the package will build now and be available in a few hours. Please test and give feedback here. See https:/ /wiki.ubuntu. com/Testing/ EnableProposed for documentation how to enable and use -proposed. Thank you in advance!