"Drivers have been made to behave when using a bigger than 128KB maximum IO transfer size"
wojtek at wojtek.tensor.gdynia.pl
Tue May 13 02:02:14 PDT 2014
> (x86_64/amd64) by default.
> I experimented for a while with the ahci driver; bigger values helped to
> increase linear (dd) performance by up to 20% with fast SSDs but it was unclear
> at the time if it would have improved regular filesystem operations.
it should when performing parallel reads/writes on multiple large files.
prevents seeking. in freebsd it makes enormous difference.
> Even though all storage drivers compile fine with bigger MAXPHYS values it's
> also possible some will have issues at runtime.
> Francois Tigeot
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