Browse Prior Art Database

Port Synchronized Adapter Tracing

IP.com Disclosure Number: IPCOM000101464D
Original Publication Date: 1990-Aug-01
Included in the Prior Art Database: 2005-Mar-16
Document File: 2 page(s) / 64K

Publishing Venue

IBM

Related People

Adkins, JT: AUTHOR [+2]

Abstract

The port-specific trace information created by multiple ports on a single adapter can be viewed in two unique sequences: either by operation on any single port or by operation on the whole adapter.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Port Synchronized Adapter Tracing

       The port-specific trace information created by multiple
ports on a single adapter can be viewed in two unique sequences:
either by operation on any single port or by operation on the whole
adapter.

      On the Multiprotocol Quad Port (MPQP) adapter, a
general-purpose base card with its own processor, DMA controllers,
timers and memory is used in conjunction with a daughter card which
contains hardware support defining the electrical interfaces and
number of ports supported.  The software which controls the adapter
resources includes interrupt service routines and a multi-priority
offlevel work processing environment.  The software which controls
many adapter functions runs natively on the adapter and cannot be
viewed using available debug tools.  During problem investigation,
the tracing facility may be used to view activity on the adapter from
the host.  This allows adapter activity to be viewed without external
debugging tools, such as an in-circuit emulator.

      The multiport nature of the MPQP adapter presented a problem in
creating trace information which included information to synchronize
the activity of different ports. This was necessary, in many cases,
because diagnosis of a problem on one port is directly impacted by
activity on the others.  Yet in traditional debuggers, trace elements
from the unaffected port could fill the trace buffer and prevent
necessary data on the failing port to be included in the trace.

      With the invention, tracing is independently...