On Fri, 2012-06-29 at 16:54 +0200, Andreas Gruenbacher wrote:

The MSG_NEW_PACKET flag indicates to sendmsg / sendpage that the message or
page should be put into a new packet even when there is still room left in the
previous packet.

In the tcp protocol, messages which are not sent immediately are queued.  When
more data is sent, it will be added to the last segment in that queue until
that segment is "full" whenever possible; only then is a new segment added.
Right now, there is no way to indicate when tcp should start a new segment.
The new flag allows to control that.

Signed-off-by: Andreas Gruenbacher <redacted>
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I don't understand how maintaining any message boundaries at sender can
prevent any middlebox or the receiver to coalesce frames to any
boundaries it prefers ?