Re: [PATCH] zerocopy NFS updated

[Trond Myklebust]

>>>>> " " == Hirokazu Takahashi <[e-mail]> writes:

     > Hi, I've been thinking about your comment, and I realized it
     > was a good suggestion.  There are no problem with the zerocopy
     > NFS, but If you want to use UDP sendfile for streaming or
     > something like that, you wouldn't get good performance.

Surely one can work around this in userland without inventing a load
of ad-hoc schemes in the kernel socket layer?

If one doesn't want to create a pool of sockets in order to service
the different threads, one can use generic methods such as
sys_readahead() in order to ensure that the relevant data gets paged
in prior to hogging the socket.

There is no difference between UDP and TCP sendfile() in this respect.

Cheers,
  Trond