lkml.org 
[lkml]   [2001]   [Feb]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Flushing buffer and page cache
James Bottomley wrote:

> > Is it possible to flush all entries in the buffer cache corresponding
> > to a single block device (i.e. simply drop them if they aren't dirty,
> > or write them to disk and drop them after this if they are dirty)?
>
> Yes, just send the BLKFLSBUF ioctl to the device this syncs the device then
> removes all the buffers from the cache. We use it as a tool to move a SAN
> device around a cluster, which is similar to what you want to do.

Last time this question was raised, someone mentioned
a little utility called flushb . Here is its source:

/*
* flushb.c --- This routine flushes the disk buffers for a disk
*/

/*
* modified August 2000 by Juri Haberland
* juri.haberland@innominate.de
*/

#include <stdio.h>
#include <fcntl.h>
#include <linux/fs.h>

#define NOARGS void

const char *progname;

static void usage(NOARGS)
{
fprintf(stderr, "Usage: %s disk\n", progname);
exit(1);
}

int main(int argc, char **argv)
{
int fd;

progname = argv[0];
if (argc != 2)
usage();

fd = open(argv[1], O_RDONLY, 0);
if (fd < 0) {
perror("open");
exit(1);
}
/*
* Note: to reread the partition table, use the ioctl
* BLKRRPART instead of BLKFSLBUF.
*/
if (ioctl(fd, BLKFLSBUF, 0) < 0) {
perror("ioctl BLKFLSBUF");
exit(1);
}
return 0;
}
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:15    [W:0.245 / U:0.320 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site