Andrea Arcangeli wrote:
On Tue, Oct 05, 2004 at 05:36:06PM +0100, P@xxxxxxxxxxxxxx wrote:
So can anyone summarise the relative merits of these locking
mechanisms, before I start benchmarking?
frlock/seqlock (2.4/2.6 respectively) is the way to go, no write
starvation, and zero cacheline bouncing.
Cheers.
Perhaps the confusing comment wrt brlock at the
top of seqlock.h can be changed so?
upgrade to x86-64, there I implemented gettimeofday with vsyscalls which
also avoids entering exiting userspace which becomes the by far biggest
overhead after using seqlock. (speedup is tenfold or so)
This is all in kernel space.
However Stephen's suggestion of reading the tsc in user space
may be a runner, as I just care about relative times.
thanks guys!
Pádraig.
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