Re: DMA transfers in 2.5.67

Måns Rullgård (mru@users.sourceforge.net)
16 Apr 2003 12:13:09 +0200


Andrew Morton <akpm@digeo.com> writes:

> > # mount /ext3_fs
> > # time dd if=/ext3_fs/100MiB_file of=/dev/null bs=32k
> >
> > 2.4.20aa1 : 3.3 sec (exactly what I expect to see)
> > 2.5.66 : 6.6 sec
>
> With this test 2.4 will leave a lot more unwritten dirty data in memory.
>
> You should include a `sync' in the timings.

That was reading a file discarding that data. A sync shouldn't make
any difference.

-- 
Måns Rullgård
mru@users.sf.net
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