From: Trond Myklebust <trond.myklebust@fys.uio.no>
Subject: Re: question on sk_sem within svc_sendto
Date: 30 Apr 2003 17:30:23 +0200
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To: "Wendy Cheng" <s_wendy_cheng@hotmail.com>
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>>>>> " " == Wendy Cheng <s_wendy_cheng@hotmail.com> writes:

     > We're in the middle of fine-tuning our linux-based file server
     > and currently examining the NFS zero-copy path with 2.5.x
     > kernel. There is a semaphore (sk_sem) within svc_sendto() that
     > serializes the outgoing data. Could someone shed some light and
     > give us an explanation why this semaphore is needed - just for
     > education purpose.Great thanks...

You need to send one datagram at a time down each socket otherwise the
client might receive data which is partially from one request,
partially from another.

Cheers,
  Trond


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