Large disk with small allocation unit size cause corrupt exFAT file system

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I want to create a 25000MB RAMdisk with exFAT filesystem. Since I have an extremely large amount of small data, I set the Allocation Unit Size to 2K. If I now let the chkdsk tool run over it I get "corruption was found when examining files in this directory". When I copy my data to the RAMdisk, I get a lot of error messages from my application, because the filesystem is corrupt. If I format the RAMdisk with exFAT and 2K blocks, the filesystem is not corrupt and I do not get any error messages. Since SoftPerfect RAM Disk is used on a BuildServer to speed up the build process, it is not possible to format the RAM Disk manually after each reboot.

P.S. The same error occurs on exFAT with 4K clusters.
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Re: Large disk with small allocation unit size cause corrupt exFAT file system   16 September 2020, 10:18

Thank you for reporting this. The exFAT formatting issue has been fixed, for both 2K and 4K clusters. You can download the update here.

The problem was due to incorrect FAT bitmap creation for larger FAT tables -- exactly what happen in the case of a large drive with a small cluster size.
Thank you very much for the quick fix of the error. I have tested it and the error does not occur anymore.

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