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Mick <michaelkintzios@×××××.com> wrote: |
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> I was wondering similar questions regarding a 32G flash card I have. |
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> Using fdisk to partition it the starting sector was automatically |
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> aligned with 2048 as it fdisk has been improved to deal with 4KB |
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> sector drives. |
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> |
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> However, formatting it with mkfs.vfat I was none the wise if I should |
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> use the '-s sectors-per-cluster' option or what to set it at. |
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For the SD Cards of my Android devices I use |
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mkfs.vfat -F32 -s64 |
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This always gave me good performance. |
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> Furthermore, how can I read the current cluster size off the flash |
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> card? Is this appropriate? |
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> |
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> blockdev --getbsz /dev/sdb |
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> 4096 |
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This gives you the physical blocksize of the device. |
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If you wanna know the cluster size, that means the blocksize of your |
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filesystem, you can use mtools. First configure /etc/mtools/mtools.conf |
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and set a drive letter for your SD Card, e.g. |
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drive c: file="/dev/sde1" |
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then use |
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minfo C: |
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to query a lot of information about the filesystem. Beside some other infos |
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you will get for example: |
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sector size: 512 bytes |
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cluster size: 8 sectors |
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This means cluster size is 4096 Bytes. |
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-- |
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Regards |
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wabe |
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