PUFFS performance on netbsd-6

[Emmanuel Dreyfus <manu%netbsd.org@localhost>]

Hi

I am runnning my usual perfuse test case on netbsd-6: building the 
netbsd tree. Performances are much lower than on netbsd-5.

A quick dump of FUSE operations shows that the thing spends most 
of its time on lookups. It will exhibit behavior like this:
LOOKUP a
LOOKUP a/b
LOOKUP a/b/c
LOOKUP a/b/c/d
GETATTR a/b/c/d
LOOKUP a
LOOKUP a/b
LOOKUP a/b/c
LOOKUP a/b/c/e
GETATTR a/b/c/e

It seems that while the kernel still knows about a/b/c (it was not
reclaimed), it still have to lookup from the root. Is that on purpose?
If it is, then what is the rationale?

I have not yet tested on -current.

-- 
Emmanuel Dreyfus
manu%netbsd.org@localhost