direct-io regression [Was: How to track down abysmal performance ata - raid1 - crypto - vg/lv - xfs]

[Jeff Moyer]

Chris Mason <chris.mason at oracle.com> writes:

> But, I'm surprised your drive is doing 8K dio reads at 16MB/s, that
> seems a little high.  

I'm not sure why you think that.  We're talking about a plain old SATA
disk, right?  I can get 40-50MB/s on my systems for 8KB O_DIRECT reads.
What am I missing?

Cheers,
Jeff