lkml.org 
[lkml]   [1999]   [Mar]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: RFC: invalidateCaches(fd) interface
Hi,

On Sat, 06 Mar 1999 11:38:34 -0800, lm@bitmover.com (Larry McVoy)
said:

> I've been unable to find an interface in Linux which will flush just
> a single file's data from the buffer/page cache[s]. I used to do
> this on Sun's with an mmap() and then an msync(MS_INVALIDATE) but
> that doesn't seem to work in Linux. Does anyone have a patch to do
> this and would there be any interest in a /proc interface to do
> this? I'd like to be able to do

> echo /home/lm/tmp/BIGFILE > /proc/invalidate

> and have it do it.

The December ;Login: had an update on the Posix.1d standards WIP which
addressed this with an IO advisory function:

posix_fadvise(fd, code, start, length);

which defines advise codes

POSIX_FADV_NORMAL: no special treatment
POSIX_FADV_SEQUENTIAL: expect sequential access
POSIX_FADV_RANDOM: expect random access
POSIX_FADV_WILLNEED: expect access to given range soon
(ie. preload cache)
POSIX_FADV_DONTNEED: don't need the given range any more
POSIX_FADV_NOREUSE: don't expect reuse of this data after the
first access

Would this satisfy your requirements if implemented for Linux?
POSIX_FADV_DONTNEED would seem to be what you are after.

--Stephen


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

\
 
 \ /
  Last update: 2005-03-22 13:50    [W:0.049 / U:0.040 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site