[ENBD] Doubled requests

[Arne Wiebalck]

On Tue, 13 Jan 2004, Peter T. Breuer wrote:

> > I'll add some code to my device to notify me if it sees requests to the
> > same block. Maybe we can conclude something if we see the request series
> > to be
> >
> >   .. 22 23 24 25 25 26 27 ...
> >               ^^^^^
> >
> > or
> >
> >   .. 22 23 24 25 26 27 28 ... 110 25 111 112 113 ...
> >               ^^                  ^^


It seems to be the first case, the writes to the same blocknr follow each
other directly.

The last and the current request go to the same block.
(the number is the block number, the hex number is the pointer to the bh
struct of that and the last request)

    Jan 13 17:47:52 e005 kernel: cr: Suspicious block number: 1793 (last
    1793) d3ea02a0 (d3ea02a0)

it is the same bh, shouldn't it be a different one?
some more twins:

    Jan 13 17:47:54 e005 kernel: cr: Suspicious block number: 11777 (last
    11777) de6748c0 (de6748c0)
    Jan 13 17:47:56 e005 kernel: cr: Suspicious block number: 21636 (last
    21636) d7d31140 (d7d31140)


(the next ones are different: they are simply late)

    Jan 13 17:47:56 e005 kernel: cr: Suspicious block number: 24697 (last
    24710) d3cfeb00 (d3cfeec0)
    Jan 13 17:47:56 e005 kernel: cr: Suspicious block number: 24698 (last
    24716) d3cfeaa0 (cc0fb3c0)


(here comes another doubled request)

    Jan 13 17:47:58 e005 kernel: cr: Suspicious block number: 31265 (last
    31265) c0ac9c60 (c0ac9c60)



shouldn't we have different bhs for different requests?


arne


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 Arne Wiebalck                        Kirchhoff Institute for Physics
                                           Technical Computer Science
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