Re: dd: avoid swap and benchmark of the nocache option

[Francois]

On 11 January 2016 at 23:55, Pádraig Brady <address@hidden> wrote:
> On 11/01/16 21:59, Francois wrote:

>> - and maybe that we can do a better use of posix_advise.
>
> What do you mean for that do do exactly?

nocache limits itself to advising a single buffer, while what we really
want is to tell the kernel it's really the full file we don't need in
cache.  Doing a ADV_DONTNEED starting from offset 0 each time
drastically reduce the number of pages put into cache, and completely
removes swapping, and this *without sync*.

Cheers, and thanks for the example!
Thanks for your time

Francois