Subject: SoC/Projects fast clock_gettime, gettimeofday, time
To: None <firstname.lastname@example.org>
From: Frank Kardel <email@example.com>
Date: 05/02/2006 21:26:08
I'd like to add an item to the projects page regarding fast
clock_gettime in conjunction with timecounters.
Any (quick SoC people are looking already) feedback
would be appreciated.
Light weight precision user level time reading
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
clock_gettime(), time(), gettimeofday(). With the availability of
user level readable high frequency counters it is possible to
create fast implementations for precision time reading if the
hardware supports it. Optimizing clock_gettime and alike will
reduce the strain from applications frequently calling it an
improve timing information quality for applications like NTP.
The implementation would be based on a to be modified version
of the timecounters implementation in NetBSD.
Estimated time: 1-2 months
Contact(s): [tech-kern, firstname.lastname@example.org]
See also: [http://phk.freebsd.dk/pubs/timecounter.pdf]