First access to mounted jffs2 partition is slow
michael
trimarchi at gandalf.sssup.it
Tue Feb 12 13:03:56 EST 2008
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
More information about the linux-mtd
mailing list