2,305 research outputs found
CHECKPOINTING AND RECOVERY IN DISTRIBUTED AND DATABASE SYSTEMS
A transaction-consistent global checkpoint of a database records a state of the database which reflects the effect of only completed transactions and not the re- sults of any partially executed transactions. This thesis establishes the necessary and sufficient conditions for a checkpoint of a data item (or the checkpoints of a set of data items) to be part of a transaction-consistent global checkpoint of the database. This result would be useful for constructing transaction-consistent global checkpoints incrementally from the checkpoints of each individual data item of a database. By applying this condition, we can start from any useful checkpoint of any data item and then incrementally add checkpoints of other data items until we get a transaction- consistent global checkpoint of the database. This result can also help in designing non-intrusive checkpointing protocols for database systems. Based on the intuition gained from the development of the necessary and sufficient conditions, we also de- veloped a non-intrusive low-overhead checkpointing protocol for distributed database systems.
Checkpointing and rollback recovery are also established techniques for achiev- ing fault-tolerance in distributed systems. Communication-induced checkpointing algorithms allow processes involved in a distributed computation take checkpoints independently while at the same time force processes to take additional checkpoints to make each checkpoint to be part of a consistent global checkpoint. This thesis develops a low-overhead communication-induced checkpointing protocol and presents a performance evaluation of the protocol
Checkpointing as a Service in Heterogeneous Cloud Environments
A non-invasive, cloud-agnostic approach is demonstrated for extending
existing cloud platforms to include checkpoint-restart capability. Most cloud
platforms currently rely on each application to provide its own fault
tolerance. A uniform mechanism within the cloud itself serves two purposes: (a)
direct support for long-running jobs, which would otherwise require a custom
fault-tolerant mechanism for each application; and (b) the administrative
capability to manage an over-subscribed cloud by temporarily swapping out jobs
when higher priority jobs arrive. An advantage of this uniform approach is that
it also supports parallel and distributed computations, over both TCP and
InfiniBand, thus allowing traditional HPC applications to take advantage of an
existing cloud infrastructure. Additionally, an integrated health-monitoring
mechanism detects when long-running jobs either fail or incur exceptionally low
performance, perhaps due to resource starvation, and proactively suspends the
job. The cloud-agnostic feature is demonstrated by applying the implementation
to two very different cloud platforms: Snooze and OpenStack. The use of a
cloud-agnostic architecture also enables, for the first time, migration of
applications from one cloud platform to another.Comment: 20 pages, 11 figures, appears in CCGrid, 201
A Survey of Fault-Tolerance and Fault-Recovery Techniques in Parallel Systems
Supercomputing systems today often come in the form of large numbers of
commodity systems linked together into a computing cluster. These systems, like
any distributed system, can have large numbers of independent hardware
components cooperating or collaborating on a computation. Unfortunately, any of
this vast number of components can fail at any time, resulting in potentially
erroneous output. In order to improve the robustness of supercomputing
applications in the presence of failures, many techniques have been developed
to provide resilience to these kinds of system faults. This survey provides an
overview of these various fault-tolerance techniques.Comment: 11 page
Sensornet checkpointing: enabling repeatability in testbeds and realism in simulations
When developing sensor network applications, the shift from
simulation to testbed causes application failures, resulting in additional
time-consuming iterations between simulation and testbed. We propose
transferring sensor network checkpoints between simulation and testbed
to reduce the gap between simulation and testbed. Sensornet checkpointing
combines the best of both simulation and testbeds: the nonintrusiveness
and repeatability of simulation, and the realism of testbeds
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