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From: David Woodhouse <dwmw2@infradead.org>
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To: Ian Campbell <icampbell@arcom.co.uk>
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Subject: Re: Caching of reads 
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Date: Fri, 16 Nov 2001 15:48:29 +0000
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icampbell@arcom.co.uk said:
>  It seems as if reads from a JFFS2 file system are not being cached as
> we would expect, for instance this small script:

> while true ; do sleep 1; done

> causes a read from the flash every time the sleep is executed. This is
> true even if the fs is mounted read only. 

Strange. JFFS2 doesn't do caching - that's supposed to be handle by the 
Linux VFS/VM. But set CONFIG_JFFS2_FS_DEBUG=1 and 
echo 9 > /proc/sys/kernel/printk, then see what it's actually being asked 
to read each time.

--
dwmw2