using sendfile on MMAP'd buckets

[Ian Holsman]

hi.
I was looking through the sendfile code, and it looks like we could
use sendfile to transmit a memory-mapped bucket if we kept the
file-descriptor when we create the mmap bucket.
I don't have sendfile installed on solaris (yet) but I think
sendfile is faster than writeev??

if this is the case, I think we should add a function/flag/macro to the
bucket-type is_sendfileable (which would be true for files/mmaps)
instead of checking the type of the bucket explictly.

Ian
-- 
Ian Holsman
Performance Measurement & Analysis
CNET Networks    -    415 364-8608