Messages in this thread | | | From | Roger Larsson <> | Subject | Re: another IDE cleanup: kill duplicated code | Date | Tue, 12 Feb 2002 20:19:14 +0100 |
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On Tuesday den 12 February 2002 11.52, Martin Dalecki wrote: > > If you are already at it, I would like to ask to you consider seriously > the removal of the > following entries in the ide drivers /proc control files: > > [snip] > ide_add_setting(drive, "file_readahead", ... > &max_readahead[major][minor], NULL); > > Those calls can be found in ide-cd.c, ide-disk,c and ide-floppy.c > > [snip] > > The second of them is trying to control a file-system level constant > inside the actual block device driver. > This is a blatant violation of the layering principle in software > design, and should go as soon as > possible.
It really should go (the only one working is for ide-disk) but you need to add another way to tune readahead per disk too...
Tuning this parameter gives quite a bit improved performance when reading from several big files at a time! A diff of two big files is enough to show it: from 10MB/s to 25MB/s (2.4.17-rc1) (due to less time lost seeking)
/RogerL
-- Roger Larsson Skellefteå Sweden - 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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