2001-10-08 10:20:42

by kladit

[permalink] [raw]
Subject: 2.4.11.p4 and dd

dd does not work anymore.

dd if=/dev/sda of=/dev/sdb bs=1024k

stops with "File size limit exceeded"

Using kernel 2.4.3 the same command works fine.

2.4.3 uses a large amount of buffer, 2.4.11p4 only chache.
2.4.3 doesn't swap, 2.4.11p4 eats up 1 GB RAM and 100 MB swap.

--
Best regards
Klaus Dittrich

e-mail: [email protected]


2001-10-08 11:44:58

by Tobias Ringstrom

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Subject: Re: 2.4.11.p4 and dd

On Sun, 7 Oct 2001, Klaus Dittrich wrote:

> 2.4.3 uses a large amount of buffer, 2.4.11p4 only chache.

Block devices are handled by the page cache in 2.4.10 and up.

> 2.4.3 doesn't swap, 2.4.11p4 eats up 1 GB RAM and 100 MB swap.

This is a bug in pre4. Please try pre5 instead!

/Tobias

2001-10-08 12:04:19

by Stephan von Krawczynski

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Subject: Re: 2.4.11.p4 and dd

On Sun, 7 Oct 2001 20:35:40 +0200 [email protected] (Klaus Dittrich) wrote:

> dd does not work anymore.
>
> dd if=/dev/sda of=/dev/sdb bs=1024k
>
> stops with "File size limit exceeded"
>
> Using kernel 2.4.3 the same command works fine.
>
> 2.4.3 uses a large amount of buffer, 2.4.11p4 only chache.
> 2.4.3 doesn't swap, 2.4.11p4 eats up 1 GB RAM and 100 MB swap.

Please try 2.4.11-pre5.
pre4 is seriously broken regarding high vm loads.

Regards,
Stephan

2001-10-09 07:03:09

by Constantin Loizides

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Subject: Re: 2.4.11.p4 and dd

Hi!

> > 2.4.3 uses a large amount of buffer, 2.4.11p4 only chache.
>
> Block devices are handled by the page cache in 2.4.10 and up.
>

Eh, did I miss something? Thought, that meta data are still
cached in buffer cache? Did it change from 2.4.9 to 2.4.10?
What about the ac kernels?

Constantin

2001-10-09 20:55:22

by Mike Fedyk

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Subject: Re: 2.4.11.p4 and dd

On Tue, Oct 09, 2001 at 09:03:12AM +0200, Constantin Loizides wrote:
> Hi!
>
> > > 2.4.3 uses a large amount of buffer, 2.4.11p4 only chache.
> >
> > Block devices are handled by the page cache in 2.4.10 and up.
> >
>
> Eh, did I miss something?

Yes.

>Thought, that meta data are still
> cached in buffer cache?

FSes still use the buffer cache, but the block devices now use page cache.

>Did it change from 2.4.9 to 2.4.10?

Yes, in 2.4.10pre11

> What about the ac kernels?
>

Block devices use Buffer Cache. Alan has stated that he doesn't plan to
merge this change any time soon, if at all.

> Constantin

Mike