Comment 22 for bug 247819
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| Rocko (rockorequin) wrote Re: SDHC Card reader I/O errors on Hardy | #22 |
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1b1ed1a
(Get the code!)
I've noticed that the write errors occur more frequently when the system is under load, eg while copying large amounts of data between USB drives, and when free memory is low.
The last time it happened, I was only running firefox and nautilus, so the available memory (almost 3.5 GB was taken) must have been mostly taken up by I/O buffering. I had to try ten times to write an 800 MB file to the SD card, and it was only successful once the USB drives had finished transferring data.
So does the kernel have timing, interrupt, or memory access problems that affect the mmcblock driver when USB usage is high and/or memory is running low?
Another observation that surprises me is that when I transfer large files between USB drives or to the SD card, the internal hard drive (ie the /dev/sda drive) is accessed a lot. With so much available RAM I wouldn't have though the file I/O system would need to resort to using /dev/sda.