Problem - Apar IY12785
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AIXLINK/X.25 encounters severe performance problems with bos.mp 
(and bos.up) 4.3.3.16 and later. You may also encounter can't
download microcode problems with "cfgsx25: tw_get(PH_OK_ACK) failed"
or "cfgsx25: tw_get(DL_OK_ACK) failed" when trying to make a port.

Environment
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AIX 4.3.3 with bos.mp/up 4.3.3.16 or later, AIXLINK/X.25 1.1.5.+
with IBM ARTIC960Hx 4-Port Selectable PCI Adapter.

Cause
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The X.25 driver twd does not correctly handle sharing of interrupts 
implemented in bos.mp (and bos.up).4.3.3.16 and later. Drivers
'twd' and 'ddriciop' are competing with each other for the same 
interrupt which cause delays in processing the X.25 data stream.

Relief
-----
Install the workaround kernel in 22035.kernel.tar.Z which has 
interrupt sharing disabled. Make sure that the system is upgraded 
to bos.up.4.3.3.23 or bos.mp.4.3.3.23 (depending on the system)
before installing these kernels. There is an 'mp' kernel and a
'up' kernel README for each unix included. After uncompressing
and untarring 22035.kernel.tar.Z, FOLLOW THE INSTRUCTIONS IN
unix_mp.README or unix_up.README, depending on the system.

Limitations
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The workaround kernel will not work if the customer is running
4.3.3.24 or later. In such cases, another workaround kernel is
needed. Please contatct the X.25 support team in this case.