Attendees present:
Ron Brightwell (Sandia)
Joel Clark (Intel)
Robert George (MSU)
Shane Hebert (MSU)
Arkady Kanevsky (MITRE)
Koichi Konishi (NEC)
Llyod Lewins (Hughes)
Arindam Saha (MSU)
Lance Shuler (Sandia)
Steven Taylor (CalTech)
- Insufficient participation in Vienna, no minutes
- MPI/RT will not determine but provide tools to implement the following
paradigms:
* priority based
* time driven
* event driven
* ad hoc
- MPI/RT will not replace the native runtime system or scheduler, but will
provide a portable API to these systems
- Embedded MPI will not have the full functionality of MPI/RT
* core will provide basic sends/receives, collective, and datatypes
* remaining functionality to be added on layers
- Abstraction of Layers
APPLICATION
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SYSTEMS PROCESSES |
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MPI/RT / / / /
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KERNEL
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- "info" is a mechanism for application to communicate with the kernel
* signals in addition to KILL are required like SLEEP, RESUME, etc.
* we may communicate start time, priority, deadline to the kernel
- "notify" may be a mechanism to transmit information from kernel to the
application
- TIMEOUTS will be provided both on the sender and the receiver sides
* can be added unobtrusively with MPI_WAIT
- MPI/RT will provide access to a globally synchronized clock
* essential for time driven
* use one if available
* software synchronize if not available
- predicatabilty and QoS guarantees are important
* virtual channels may be one way to do it
- message scheduling will be by passing the opaque INFO argument at the time
of creation of the communicator
- develop a reprsentative suite of real world applications for
proof-of-concept
- preemption needed (especially to minimize priority inversion)
- fault tolerance is a desirable feature
* PERHAPS IT'S TIME TO HAVE A SERIOUS PROPOSAL ON FAULT TOLERANCE
If you have any comments please contact me.
Thanks.
-Arindam Saha
Mississippi State University
saha@erc.msstate.edu
601 325 2168