In message <[EMAIL PROTECTED]>
Dan Sugalski <[EMAIL PROTECTED]> wrote:
> I don't much care how its faked (if it is) as long as it
> works. Might not be as efficient as full kernel support for async
> I/O, but it'll do. At least there's some overlap. (You can get
> better device request ordering and do I/O coalescing if you have
> more than one request handy)
The problem when I last tried it was that AIO was actually
less efficient than doing sync IO myself. It might sound
incredible to somebody used to using VMS async IO like myself
but it seemed to be true.
Part of it was probably the slowdown that occurred as soon
as I had to compile -D_REENTRANT and pull in the thread
support library with its thread safe versions of various
library routines, and part of it that most of my testing was
on Unixware where the filing system was vxfs and sync IO goes
like a train.
Tom
--
Tom Hughes ([EMAIL PROTECTED])
http://www.compton.nu
