Re: sandisk cruzer mini quirks [failure] on RELENG_4

From: ALeine (aleine_at_austrosearch.net)
Date: 02/26/05

  • Next message: Peter C. Lai: "Re: sandisk cruzer mini quirks [failure] on RELENG_4" 
    Date: Sat, 26 Feb 2005 09:02:14 -0800 (PST)
To: sirmoo@cowbert.2y.net

    sirmoo@cowbert.2y.net wrote:

    > I did this as the first hack. It made the problem worse. I'll try
    > patching both umass.c and scsi_da.c maybe they will have some sort of
    > synergistic effect.

    You said the problem occurs only when you copy files to the device using
    cp(1) and not dd(1). The main difference between how cp(1) and dd(1) copy
    files (other than cp(1) mmap(2)-ing files which are <= 8 Mb in size)
    is that cp(1) copies files in 64kb (MAXBSIZE) chunks while dd(1) copies
    files in 512 byte chunks by default. They both use read(2) and write(2),
    so I would suggest using dd with bs=64k and then applying the bisection
    method to find the largest transfer block size for writing the device
    can handle.

    Does this problem occur with cpdup (ports/sysutils/cpdup) as well?
    It currently copies files in 32kb chunks, which could easily be changed
    since the transfer block size is set in a single place. You may want to
    patch cpdup to use the maximum transfer block size the device can handle
    as a temporary workaround and then use cpdup for copying files to the
    device.

    > maybe i should just bite the bullet and upgrade the box to 5.3.

    Let's hope you won't have to. :-) Can you verify that this problem does
    not occur on 5.x without upgrading (by using a FreeSBIE LiveCD)?

    ALeine
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  • Next message: Peter C. Lai: "Re: sandisk cruzer mini quirks [failure] on RELENG_4"