Annotation of wikisrc/projects/project/fast-time.mdwn, revision 1.4

1.1       jmmv        1: [[!template id=project
                      2: 
                      3: title="Light weight precision user level time reading"
                      4: 
                      5: contact="""
                      6: [tech-userlevel](mailto:tech-userlevel@NetBSD.org)
                      7: """
                      8: 
                      9: mentors="""
                     10: [Christos Zoulas](mailto:christos@NetBSD.org)
                     11: """
                     12: 
1.2       jmmv       13: category="userland"
                     14: difficulty="medium"
1.1       jmmv       15: duration="3 months"
                     16: 
                     17: description="""
1.4     ! kim        18: Design and implement a mechanism that allows for fast user level access to kernel time data structures for NetBSD. For certain types of small data structures the system call overhead is significant. This is especially true for frequently invoked system calls like [[!template id=man name="clock_gettime" section="2" collection="NetBSD-5.1"]] and [[!template id=man name="gettimeofday" section="2" collection="NetBSD-5.1"]]. With the availability of user level readable high frequency counters it is possible to create fast implementations for precision time reading. Optimizing clock_gettime(2) and alike will reduce the strain from applications frequently calling these system calls and improves timing information quality for applications like NTP. The implementation would be based on a to-be-modified version of the timecounters implementation in NetBSD.
1.3       mspo       19: 
                     20: Milestones:
                     21: 
                     22: * Produce optimizations for clock_gettime
                     23: * Produce optimizations for gettimeofday
                     24: * Show benchmarks before and after
                     25: * start evolving timecounters in NetBSD, demonstrating your improvements
1.1       jmmv       26: 
                     27: See also the [Paper on Timecounters by Poul-Henning Kamp](http://phk.freebsd.dk/pubs/timecounter.pdf).
                     28: """
                     29: ]]
                     30: 
                     31: [[!tag gsoc]]

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