In message <145c3ac8-317e-4d8b-b696-19824a6b8...@dell.com>, Paul Koning writes: >On Jan 20, 2011, at 2:47 PM, der Mouse wrote: >>> I see there is a compile time constant CACHE_LINE_SIZE in >>> <sys/param.h> which currently seems to be always be set to 64, but >>> I'm pretty certain that is not necessarily a correct value.
>> You are correct; to cite the one example I currently have swapped into >> my brain, the Super-H used in the Dreamcast has 32-byte cache lines >> (true of the I-cache and D-cache both). >I'm curious why non-kernel components would care. Look at the output of lmbench. Empirically, there are real-world performance effects in some boundary cases. Some people care about performance enough to tune for stuff like this. -s
