2002-08-05 11:28:48

by Marc-Christian Petersen

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Subject: 2.4.19' drivers/block/ll_rw_blk.c

Hi there,

could you please consider changing those very slow behaviour in
"drivers/block/ll_rw_blk.c"? ... Benchmarked against 2.4.18 this is horribly
slower ... Doing some heavy disk i/o, want to start another thing, system
freeze for some seconds ... Opening a xterm , Ctrl-D to leave, this takes
about 5 seconds and somewhat is doing flushing to the disk.

Maybe req_finished_io ?

Adrian, could this be the problem you've experienced?

Afaik this was changed for 2.4.19-pre7 and above.

--
Kind regards
Marc-Christian Petersen

http://sourceforge.net/projects/wolk

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2002-08-06 15:08:39

by Jens Axboe

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Subject: Re: 2.4.19' drivers/block/ll_rw_blk.c

On Mon, Aug 05 2002, Marc-Christian Petersen wrote:
> Hi there,
>
> could you please consider changing those very slow behaviour in
> "drivers/block/ll_rw_blk.c"? ... Benchmarked against 2.4.18 this is horribly
> slower ... Doing some heavy disk i/o, want to start another thing, system
> freeze for some seconds ... Opening a xterm , Ctrl-D to leave, this takes
> about 5 seconds and somewhat is doing flushing to the disk.
>
> Maybe req_finished_io ?
>
> Adrian, could this be the problem you've experienced?

This is a crazy bug report, sorry :-)

What slow behaviour in ll_rw_blk.c?! Consider providing vmstat when the
slowdown takes place. Also, try enable profiling if it seems like hard
system freezes.

> Afaik this was changed for 2.4.19-pre7 and above.

2.4.19-pre7 works fine, 2.4.19-pre8 stinks?

--
Jens Axboe