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A comment on Spotting and Avoiding Heap Fragmentation in Rust Applications. Parent comment

Re:Spotting and Avoiding Heap Fragmentation in Rust Applicat... by yakubin on Thursday April 06, 2023 @02:45PM (#35472613)
Filesystem may also run out of inodes, even though there is still plenty of space.
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Re:Spotting and Avoiding Heap Fragmentation in Rust Applicat... by wongarsu on Thursday April 06, 2023 @03:41PM (#35473359)
I don't think either FAT32 or NTFS suffer this problem, they allow metadata to become fragmented instead. Certainly a different design philosophy to the unixy file systems.
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Re:Spotting and Avoiding Heap Fragmentation in Rust Applicat... by magicalhippo on Thursday April 06, 2023 @06:03PM (#35475154)
NTFS most definitely suffers from this[1]. We ran into it with a customer who had a particularly fragmented database file.

IIRC it's due to a combination of relying on fixed-sized "pages" to hold fragment pointers and a limited number of page indirections. That is the root page can point to a sub-pages, which again can point to sub-pages, but those sub-sub-pages have to point to the actual fragments. Or something along those lines.

[1]: https://support.microsoft.com/en-au/topic/a-heavily-fragment...

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Re:Spotting and Avoiding Heap Fragmentation in Rust Applicat... by cryptonector on Thursday April 06, 2023 @05:24PM (#35474702)
Or you should use ZFS and not worry about that.
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