lkml.org 
[lkml]   [2001]   [Jan]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Is sendfile all that sexy?
Thus spake Ingo Molnar (mingo@elte.hu):
> > I don't know how Linux does it, but returning the first free file
> > descriptor can be implemented as O(1) operation.
> to put it more accurately: the requirement is to be able to open(), use
> and close() an unlimited number of file descriptors with O(1) overhead,
> under any allocation pattern, with only RAM limiting the number of files.
> Both of my proposals attempt to provide this. It's possible to open() O(1)
> but do a O(log(N)) close(), but that is of no practical value IMO.

I cheated. I was only talking about open().
close() is of course more expensive then.

Other than that: where does the requirement come from?
Can't we just use a free list where we prepend closed fds and always use
the first one on open()? That would even increase spatial locality and
be good for the CPU caches.

Felix
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:22    [W:0.132 / U:38.660 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site