Re: Getting 'sync' to flush disk cache?

From: Jens Axboe
Date: Mon Aug 14 2006 - 16:11:42 EST

On Mon, Aug 14 2006, Arjan van de Ven wrote:
> On Mon, 2006-08-14 at 14:39 -0400, Jeff Garzik wrote:
> > So... has anybody given any thought to enabling fsync(2), fdatasync(2),
> > and sync_file_range(2) issuing a [FLUSH|SYNCHRONIZE] CACHE command?
> >
> > This has bugged me for _years_, that Linux does not do this. Looking at
> > forums on the web, it bugs a lot of other people too.
> eh afaik 2.6.17 and such do this if you have barriers enabled...

That is correct, but it only works on reiserfs and XFS and user space
really cannot tell whether it did the right thing or not. File system
developers really should take this more seriously...

Jens Axboe

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