lkml.org 
[lkml]   [2002]   [Sep]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [RFC] mount flag "direct" (fwd)
On Wed, 4 Sep 2002, Daniel Phillips wrote:

>
> You're well wide of the mark here, in that you're relying on the assumption
> that caching is important to the application he has in mind. The raw transfer
> bandwidth may well be sufficient, especially if it is unimpeded by being
> funneled through a bottleneck like our vfs cache.
>

the fact that he is saying that this needs to run normal filesystems tells
us that.

if you need a filesystem to max out transfer rate and don't want to have
it cache things that is a VERY specialized thing and not something that
will match what NTFS/XFS/JFS/ReiserFS/ext2 etc are going to be used for.

either he has a very specialized need (in which case a specialized
filesystem is probably the best bet anyway) or he is trying to support
normal uses (in which case caching is important)

however the point is that the read-modify-write cycle is a form of cache,
it is only safe if you aquire a lock at the beginning of it and release it
at the end. A standard filesystem won't do this, this is what makes a DFS.

David Lang

-
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 13:28    [W:0.081 / U:3.480 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site