read/write multiplexed support

Christopher R. Hertel crh at
Fri May 15 03:40:48 GMT 2009

Windows servers only support the readMPX/writeMPX SMB calls over
connectionless transport (direct IPX transport--which is not NWLINK).  The
whole purpose these commands was to make optimal use of multiple transport
level connections that were bound together.  Typically this would be
multiple modem links between a remote client and a server.  MPX commands
would have no real benefit over a single-path connection oriented transport.

Chris -)-----

Marcel Müller wrote:
> I just discovered that samba 3.2.x does no longer support the TRANS2
> commands readBmpx and writeBmpx. This causes OS/2 (and eConStation)
> clients to have extremely poor performance when connecting to a samba
> server. I am talking about 2.5MB/s over switched 100baseT in read and
> write direction. Reading from Samba 3.0.24 is about 8MB/s with the same
> setup.
> It would be nice to get the support for these transfer modes back.
> Otherwise OS/2 clients are in fact restricted to samba 3.0.2x.
> Marcel

"Implementing CIFS - the Common Internet FileSystem" ISBN: 013047116X
Samba Team --     -)-----   Christopher R. Hertel
jCIFS Team --   -)-----   ubiqx development, uninq.
ubiqx Team --     -)-----   crh at
OnLineBook --    -)-----   crh at

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