Marius Negreanu

Performance Issue on Coldfire M548x.

Discussion created by Marius Negreanu on May 21, 2009
Latest reply on May 22, 2009 by Marius Negreanu

Hi,

 

I'm doing some speed tests on a M548x and it seems a bit sluggish.

 

To begin, the OS is a linux-2.6.25.20 patched using the attached list of patches.

The patches we're downloaded from www.bitshrine.org while The compiler is a

vanilla gcc-4.4.0, without the CLoop and PPL included.

cat /proc/cpuinfo
CPU:            ColdFire V4e
MMU:            ColdFire
FPU:            ColdFire V4e
Clocking:       198.2MHz
BogoMips:       198.24
Calibration:    991232 loops

Now, onto the tests.

I ran simple file copy from/to flash  to/from RAM as can be seen

in the attached bench.sh.

 

/tmp is a RAM disk and / is the flash.

 

 

This is what I got from running bench.sh on ColdFire

time cat /tmp/test_file > /dev/null
real    0m 0.09s
user    0m 0.00s
sys     0m 0.09s
time cat /tmp/test_file > /test_file
real    0m 17.81s
user    0m 0.01s
sys     0m 17.80s
time cat /test_file > /dev/null
real    0m 0.10s
user    0m 0.01s
sys     0m 0.09s
time cat /test_file > /tmp/test_file2
real    0m 0.28s
user    0m 0.02s
sys     0m 0.27s
time cat /tmp/test_file > /tmp/test_file2
real    0m 0.29s
user    0m 0.00s
sys     0m 0.29s
/tmp

 

 

The same test  was performed on an ARM

cat /proc/cpuinfo
Processor       : ARM920T rev 0 (v4l)
BogoMIPS        : 99.73
Features        : swp half thumb crunch

 

 

With the following results:

 

time cat /tmp/test_file > /dev/null
real    0m 0.04s
user    0m 0.00s
sys     0m 0.04s
time cat /tmp/test_file > /test_file
real    0m 11.28s
user    0m 0.00s
sys     0m 7.15s
time cat /test_file > /dev/null
real    0m 0.04s
user    0m 0.00s
sys     0m 0.03s
time cat /test_file > /tmp/test_file2
real    0m 0.07s
user    0m 0.00s
sys     0m 0.05s
time cat /tmp/test_file > /tmp/test_file2
real    0m 0.06s
user    0m 0.00s
sys     0m 0.06s
/tmp

 

 

You can see that the test `time cat /tmp/test_file > /tmp/test_file2` performs real bad on

the ColdFire.

 

 

Have you any clues on this one ?

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