Linus Torvalds wrote:
It's not magic, and it's not all that recent. Linux FS ops have always
been pretty good, and the dentry cache was introduced in 2.0.x, I think,
so you'd be hard-pressed to find a Linux system that doesn't have it.
2.1.14, I seem to remember -- it was definitely 2.1.1x-ish. I mostly
recall because autofs didn't just break horribly, it took adding several
dcache hooks to make it work again :)
-hpa