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Hi Rainer, |
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On Friday, 27 November 2020 16:01:29 GMT Dr Rainer Woitok wrote: |
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> Since the USB sticks contain symbolic links and have to be accessible |
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> from both, Linux and Windows they are NTFS formatted, and according to |
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> "mkntfs(8)" the sector size can be at most 4096, while the cluster size |
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> is limited to 2097152, that is 2G. However, when NTFS formatting an USB |
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> stick from within TrueCrypt/VeraCrypt or directly in Windows the maximum |
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> cluster size is 64K, with the only difference that Windows calls it |
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> "allocation unit size". |
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Ohh! STOP RIGHT THERE! :-) |
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I mistakenly thought you were using FAT. NTFS on linux uses the ntfs-3g |
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driver, which relies on FUSE. This 'Filesystem in Userspace' is inevitably |
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slower than kernel filesystem drivers, because it has to jump through hoops |
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and libs, acting as a virtual filesystem. CPU usage will also be higher as a |
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result, than when using a native kernel filesystem driver. |
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A 4k block size is recommended for ntfs-3g which is the default sector created |
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by fdisk and friends on Linux these days. This will align your partition |
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optimally. In addition, mkfs.ntfs will use 4096 bytes as the default cluster |
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size, so you should be good in that respect. |
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Another setting you may want to try is mounting the USB with 'big_writes' - |
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check the man page. This should help particularly with large files, which |
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will use larger blocks up to 128KB when copying data to the NTFS. |
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Also, read the FAQs under the heading "Performance" for more useful |
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information: |
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https://www.tuxera.com/community/ntfs-3g-faq/ |
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Hope this helps. |
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