Re: vectorized fsyncv(2) syscall -- useful?

["Edward B. DREGER" <eddy+public+spam%noc.everquick.net@localhost>]

DL> Date: Sat, 10 Oct 2009 18:37:03 +0100
DL> From: David Laight

DL> > A context switch per syscall.
DL>
DL> There is unlikely to be a full context switch. Provided the process
DL> isn't pre-empted syscalls are relatively cheap (except on ARM).

Then I was recalling dated/erroneous information.  Thanks.


[ snip EBD citation of readv(2) and writev(2) ]

DL> One purpose of these calls is that they are atomic (or, at least, as
DL> atomic a single read/write) - this can be important.

True.


DL> There is no reason to complicate the syscall interface any further!
DL> I'd guess that any apparant gains are overwhelmed by the additional
DL> complexity.

Or that any additional complexity is underwhelmed by the apparent gains.
;-)

Thanks again to you and Bill for the feedback and insight.


Eddy
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