Filesystems and case-insensitivity

Posted Nov 28, 2018 20:54 UTC (Wed) by saffroy (guest, #43999)
Parent article: Filesystems and case-insensitivity

The question of negative cache entries is interesting, and I confirm it is very important for performance.

I didn't look at the dentry cache in a very long time, though I suppose that looking up a dcache entry by name is essentially: compute a hash of the (name, directory ino) tuple, then look it up in a hash table, by comparing the requested tuple with the cached tuples in the bucket.

Then, I suppose it is sufficient to have a per-filesystem hash function, which can compute a hash over the normalized name. And a per-filesystem comparison function can then compare the requested tuple with the cached tuples.

Probably that would work, right?