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



Regular RPI / RPI2 kernel build does this for you -- simply rename "netbsd.bin" to "kernel.img".

On Tue, 18 Aug 2015, Stephan wrote:

Sorry, I meant objcopy (it was already too late yesterday). I need a kernel.img file for the boot partition on
the Pi. Jared said that needs to be extracted from the ELF kernel resulting from a regular build.

2015-08-18 12:55 GMT+02:00 Nick Hudson <skrll%netbsd.org@localhost>:
      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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