InodeEntry held its one path in a slice, so every inode the kernel references
cost a 16-byte backing array and a second heap object on top of the 32-byte
entry. The extra links of a hard-linked file now hang off a pointer instead,
which keeps the struct in the same 32-byte size class and leaves the ordinary
single-link file with nothing to allocate.
Populating the table with 1M children: 237.5 -> 221.5 B/inode at 85-character
paths, 301.3 -> 285.6 at 148.
Chris LuandGitHub
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