iPod mini Gen2: file corruption on transfer

[Kiza]

Hi,

since upgrading my iPod mini from Rockbox 3.12 to 3.13 and the internal memory from 32 to 64GB, the following problem comes up when I transfer files onto the iPod.

Hardware/Software involved:

• iPod mini Gen2
• Transcend 64GB SD-Card via a Delock SD->CF Adapter (exactly this one https://www.alternate.de/DeLOCK/Compact-Flash-Adapter-f%C3%BCr-SD-MMC-Kartenleser/html/product/792862). The SD-Card was recycled from my DSLR camera.
• Rockbox 3.13
• Linux kernel 3.13.10 (Wheezy backports kernel) on the other end

My music directory is about 45GB and is simply synced with rsync:

Code: [Select]

rsync -rv --size-only --delete --exclude-from=/home/kiza/bin/snowpod-sync.exclude /home/kiza/Music/ /media/snowpod/music/
sync

New stuff is often FLAC from bandcamp so every new album is around 400MB. sync speed is about 4MB/s, the SD-Card is quite slow. I often get a hung_task_timeout from the kernel during syncing.

Code: [Select]

May  1 00:37:18 blackbook kernel: [27964.552410] INFO: task sync:25564 blocked for more than 120 seconds.
May  1 00:37:18 blackbook kernel: [27964.552426]       Not tainted 3.13-0.bpo.1-amd64 #1
May  1 00:37:18 blackbook kernel: [27964.552428] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
...

But now, usually one of the files was not transferred correctly. Often it is just cut off in the middle. Rerunning rsync with --checksums indeed retransfers the file.

I'm kinda lost here. I would normally blame the kernel, but it happened with different backports kernels and it started when upgrading the player to 3.13 and the 64GB card. Though I suspect the card and not 3.13. The SD-Card itself is perfectly OK even if I "tortured" it with a random card reader and even if I used the SD/CF adapter in a card reader.

Maybe the card is too slow (the previous CF was indeed much faster) and something on the player times out/terminates the write? Is there anything (syslog or something) else I could look at for more hints?

Thanks

[saratoga]

Well a bunch of USB stuff was fixed post-3.13, so updating would be the first thing i'd try.

However, you've basically got one-of-a-kind hardware here, which means troubleshooting is basically impossible.  You may just have to use the Apple firmware for USB or dive into the code and figure out why using a different drive screws up transfers (maybe some kind of timing or race condition?). 

[Kiza]

Hi Saratoga,

thanks for your reply. I already tested with a Mac and iTunes some time ago and it transfers fine.

Though you comfirmed what I already guessed, that I'm basically screwed. I will try a dev build and fiddle with the code. I almost suspect it's some sort of timing issue. If I plug the SD card into a card reader and 'dd' ~10GB of data onto it it blocks a looong time but eventually comes out fine. That was the main reason I recycled this card to use in the iPod. I will probably just get a higher quality SD card.

Thanks for your time.