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Date: Tue, 12 Feb 2008 19:03:56 +0100
From: michael <trimarchi@gandalf.sssup.it>
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To: DMcLeod <dmcleod@bittware.com>
Subject: Re: First access to mounted jffs2 partition is slow
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Cc: linux-mtd@lists.infradead.org, Will Wagner <will_wagner@carallon.com>
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Hi,
> Will Wagner wrote:
>   
>> Hello,
>>
>> I have an ARM11 system with a JFFS2 partition in NAND flash. It works 
>> but the first time it is accessed after mounting it can be very slow.
>>
>> These are the steps I am performing:
>>
>> # flash_eraseall /dev/mtd4
>> Erasing 128 Kibyte @ 5fe0000 -- 99 % complete.
>> # time mount /dev/mtdblock4 /flash -t jffs2
>> real    0m 1.25s
>> user    0m 0.01s
>> sys     0m 0.13s
>> # time ls flash		- with an empty filsystem, this takes no time
>> real    0m 0.00s
>> user    0m 0.01s
>> sys     0m 0.00s
>> # cp /sdcard/bigfile flash/	- bigfile is ~8MB
>> # umount /flash
>> # time mount /dev/mtdblock4 /flash -t jffs2
>> real    0m 2.63s
>> user    0m 0.01s
>> sys     0m 0.50s
>> # time ls flash		- first time we do this it takes a long time
>> bigfile
>> real    0m 11.79s
>> user    0m 0.00s
>> sys     0m 0.18s
>> # time ls flash		- subsequent reads are fast
>> bigfile
>> real    0m 0.00s
>> user    0m 0.01s
>> sys     0m 0.00s
>>
>>     
I think that is a problem of jffs2 and I think that is related to the 
time spent during the fstat64 system but
I'm not sure. I have little experince with jffs2.

Regards Michael