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Re: Very slow transfers to/from micro SD card on a RPi B+



On 08/17/15 19:08, Stephan wrote:
I have just rebooted with WAPBL enabled. Some quick notes:

-Sequential write speed is a little lower, around 5,4 MB/s.

-Creating 1000 files takes 0,25 sec. while almost no xfers happen. (It just
goes to the log I guess).

-When creating more files (say 10.000), a known issue comes to light. One
CPU core gets utilized 100% in kernel mode while there are almost no xfers.
It takes ages until the operation completes. In contrast, a non-WAPBL
mounted FS experiences many xfers until the drive limit gets hit (>100
xfers/sec.).

I am pretty certain that there is a regression in WAPBL. Can you tell me
how I can extract a kernel for the Pi using objdump, so I can conduct some
experimentation?

What do you want to do with objdump?

Nick



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