sendfilev vs writev

Dag-Erling Smørgrav des at
Wed Mar 4 22:37:35 CET 2009

Nils Goroll <slink at> writes:
> Which wouldn't surprise me as (at least on Solaris) sendfilev and
> writev both do scatter-gather writes when used on memory buffers. My
> understanding is that sendfilev would only be advantageous if Varnish
> actually read from file descriptors rather than from cache buffers.

It does.  That's the whole point.  But empirical testing shows that
sendfile() does not improve performance, most likely because of the
overhead of setting up the VM structures for the transfer.

Dag-Erling Smørgrav - des at

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