On Thu, 5 May 2011, Måns Rullgård wrote:
David Gilbert firstname.lastname@example.org writes:
The memcpy case is not interesting. Not at all. Most kernel memcpy calls are for small size copies. The large copy instances are just bad and misdesigned in the first place if they rely on memcpy (maybe they should simply have a custom copy function, maybe implemented with Neon).
Even outside the kernel vast memcpy's are fairly rare as far as I can tell - everyone knows they're going to hurt so people try and avoid them;
If only that were true. I have long since lost count of the times I have (in vain) told people to lose the mempcys in order to improve performance.
Keep on doing it. No amount of memcpy optimization will ever beat the performances of zero copy.