On 01/21/2012 10:54 PM, wangdi wrote:

Single directory performance is a critical in some use cases. For 
example the multiple application threads might create hundreds of 
thousands of files in a single directory simultaneously within a short 
window of time.

read NFSD here ;-)

Currently, both filename lookup and file system modifying operations 
(such as create and unlink) are protected with a single lock for the 
entire directory. It might be useful to remove this lock, so multiple 
application threads can access the directory simultaneously.

I agree about create, unlink, and so on. But don't we have some lockless
look up in place since a few Kernels ago?

But yes the topic is very interesting, though I'd suspect its hard to
implement.

Thanks
WangDi

Thanks
Boaz