From ee947ab4eff2bda9bc6409ed69f6f68b5164602e Mon Sep 17 00:00:00 2001 From: antrik Date: Fri, 25 Mar 2011 10:20:54 +0100 Subject: gsoc/ideas/dtrace: Update and add back Doesn't look like Andrei will ever continue work on this, so it's up for takers again. Mention previous work, and update task accordingly. --- community/gsoc/project_ideas.mdwn | 1 + community/gsoc/project_ideas/dtrace.mdwn | 51 +++++++++++++++++++------------- 2 files changed, 32 insertions(+), 20 deletions(-) (limited to 'community/gsoc') diff --git a/community/gsoc/project_ideas.mdwn b/community/gsoc/project_ideas.mdwn index b4b60dd6..0c249b62 100644 --- a/community/gsoc/project_ideas.mdwn +++ b/community/gsoc/project_ideas.mdwn @@ -108,3 +108,4 @@ See also the list of [Hurd-related X.org project ideas](http://wiki.x.org/wiki/H [[!inline pages="community/gsoc/project_ideas/xattr" show=0 feeds=no actions=yes]] [[!inline pages="community/gsoc/project_ideas/valgrind" show=0 feeds=no actions=yes]] [[!inline pages="community/gsoc/project_ideas/driver_glue_code" show=0 feeds=no actions=yes]] +[[!inline pages="community/gsoc/project_ideas/dtrace" show=0 feeds=no actions=yes]] diff --git a/community/gsoc/project_ideas/dtrace.mdwn b/community/gsoc/project_ideas/dtrace.mdwn index ebb63d48..f70598ca 100644 --- a/community/gsoc/project_ideas/dtrace.mdwn +++ b/community/gsoc/project_ideas/dtrace.mdwn @@ -9,7 +9,7 @@ Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled [[GNU Free Documentation License|/fdl]]."]]"""]] -[[!meta title="dtrace Support"]] +[[!meta title="Kernel Instrumentation"]] One of the main problems of the current Hurd implementation is very poor [[open_issues/performance]]. While we have a bunch of ideas what could cause the performance @@ -25,25 +25,36 @@ situations occur, how things interact, etc. It could also prove helpful in debugging some issues that are otherwise hard to find because of complex interactions. -The most popular framework for that is Sun's dtrace; but there might be others. -The student has to evaluate the existing options, deciding which makes most -sense for the Hurd; and implement that one. (Apple's implementation of dtrace -in their Mach-based kernel might be helpful here...) - -This project requires ability to evaluate possible solutions, and experience -with integrating existing components as well as low-level programming. +The most popular kernel instrumentation framework is Sun's dtrace, +originally written for Solaris, +but also adopted by some other systems. +However, the GPL-incompatible license means it can't be used in Linux, +and thus Linux developers created their own frameworks instead: +first [[SystemTap]], and now [[LTTng]]. + +In 2008, Andrei Barbu did initial work on kernel probes for the Hurd. +However, not all of his patches got merged, +because some turned out not to be fully functional. +Also, he didn't get around to work on userspace probes, +nor on a nice frontend for writing test scripts employing the probes. + +The goal of this project is to make the instrumentation framework +more usable and complete, +and to better integrate it in the Hurd. +For that, the student will have to work +on some real profiling and/or debugging tasks, +and fix any shortcomings he encounters in the framework. + +This is a pretty involved task. +Previous experience with low-level programming is a must; +and it also requires a good grasp on interactions in complex systems. + +To work on this project, +the student will have to get familiar with GNU Mach. +(The microkernel employed by the Hurd.) +Some understanding of other aspects of the Hurd will also be required, +depending on the exact nature of the profiling/debugging performed. Possible mentors: Samuel Thibault (youpi) -Related: [[profiling]], [[LTTng]], [[SystemTap]] - -Exercise: In lack of a good exercise directly related to this task, just pick -one of the kernel-related or generally low-level tasks from the bug/task -trackers on savannah, and make a go at it. You might not be able to finish the -task in a limited amount of time, but you should at least be able to make a -detailed analysis of the issue. - -*Status*: Andei Barbu was working on -[SystemTap](http://csclub.uwaterloo.ca/~abarbu/hurd/) for GSoC 2008, but it -turned out too Linux-specific. He implemented kernel probes, but there is no -nice frontend yet. +Exercise: Use the existing probes to perform some simple measurement. -- cgit v1.2.3