Subject: Re: RAW access to files
To: der Mouse <mouse@Rodents.Montreal.QC.CA>
From: Chuck Silvers <chuq@chuq.com>
List: tech-kern
Date: 12/12/2001 22:44:14
On Wed, Dec 12, 2001 at 10:27:55PM -0500, der Mouse wrote:
> As for the memcpy, I'd rather memcpy from buffers than wait for a disk
> transfer - even a transfer that hits the disk's track cache.

given that choice, I'd choose the memory-to-memory copy as well.
but in the contexts where direct i/o is really targetted, the choice is
between "wait for a disk tranfer" and "wait for a disk transfer
and then also do the memory-to-memory", since the data is not going
to be in the file system's cache.

-Chuck