Messages in this thread | | | Date | Wed, 26 Apr 2006 13:31:14 -0700 (PDT) | From | Christoph Lameter <> | Subject | Re: Lockless page cache test results |
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Dave: Can you tell us more about the tree_lock contentions on I/O that you have seen?
On Wed, 26 Apr 2006, Jens Axboe wrote:
> On Wed, Apr 26 2006, Andrew Morton wrote: > > Christoph Lameter <clameter@sgi.com> wrote: > > > > > > On Wed, 26 Apr 2006, Andrew Morton wrote: > > > > > > > OK. That doesn't sound like something which a real application is likely > > > > to do ;) > > > > > > A real application scenario may be an application that has lots of threads > > > that are streaming data through multiple different disk channels (that > > > are able to transfer data simultanouesly. e.g. connected to different > > > nodes in a NUMA system) into the same address space. > > > > > > Something like the above is fairly typical for multimedia filters > > > processing large amounts of data. > > > > >From the same file? > > > > To /dev/null? > > /dev/null doesn't have much to do with it, other than the fact that it > basically stresses only the input side of things. Same file is the > interesting bit of course, as that's the the granularity of the > tree_lock. > > I haven't tested much else, I'll ask the tool to bench more files :) > > -- > Jens Axboe > > - 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/
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