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Transparently checkpointing MPI for fault tolerance and load balancing is a long-standing problem in HPC. The problem has been complicated by the need to provide checkpoint-restart services for all combinations of an MPI implementation over all network interconnects. This work presents MANA (MPI-Agnostic Network-Agnostic transparent checkpointing), a single code base which supports all MPI implementation and interconnect combinations. The agnostic properties imply that one can checkpoint an MPI application under one MPI implementation and perhaps over TCP, and then restart under a second MPI implementation over InfiniBand on a cluster with a different number of CPU cores per node. This technique is based on a novel "split-process" approach, which enables two separate programs to co-exist within a single process with a single address space. This work overcomes the limitations of the two most widely adopted transparent checkpointing solutions, BLCR and DMTCP/InfiniBand, which require separate modifications to each MPI implementation and/or underlying network API. The runtime overhead is found to be insignificant both for checkpoint-restart within a single host, and when comparing a local MPI computation that was migrated to a remote cluster against an ordinary MPI computation running natively on that same remote cluster.
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Transparent Checkpointing for OpenGL Applications on GPUs
This work presents transparent checkpointing of OpenGL applications, refining the split-process technique[1] for application in GPU-based 3D graphics. The split-process technique was earlier applied to checkpointing MPI and CUDA programs, enabling reinitialization of driver libraries. The presented design targets practical, checkpoint-package agnostic checkpointing of OpenGL applications. An early prototype is demonstrated on Autodesk Maya. Maya is a complex proprietary media-creation software suite used with large-scale rendering hardware for CGI (Computer-Generated Animation). Transparent checkpointing of Maya provides critically-needed fault tolerance, since Maya is prone to crash when artists use some of its bleeding-edge components. Artists then lose hours of work in re-creating their complex environment.
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- Award ID(s):
- 1740218
- PAR ID:
- 10319920
- Date Published:
- Journal Name:
- First International Symposium on Checkpointing for Supercomputing (SuperCheck21)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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