RE: [RFC PATCH 9/9] iov_iter: Add benchmarking kunit tests for UBUF/IOVEC

[David Laight]

From: David Howells
> Sent: 14 September 2023 23:15
> 
> Add kunit tests to benchmark 256MiB copies to a UBUF iterator and an IOVEC
> iterator.  This attaches a userspace VM with a mapped file in it
> temporarily to the test thread.

Isn't that going to be completely dominated by the cache fills
from memory?

I'd have thought you'd need to use something with a lot of
small fragments so that the iteration code dominates the copy.

Some measurements can be made using readv() and writev()
on /dev/zero and /dev/null.

	David

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