Abstract: Techniques for achieving application high availability via application-transparent battery-backed replication of persistent data are provided. In one set of embodiments, a computer system can detect a failure that causes an application of the computer system to stop running. In response to detecting the failure, the computer system can copy persistent data written by the application and maintained locally at the computer system to one or more remote destinations, where the copying is performed in a manner that is transparent to the application and while the computer system runs on battery power. The application can then be restarted on another computer system using the copied data.

Abstract: The disclosure provides an approach for creating a pool of memory out of local memories of host machines, and providing that pool for the hosts to use. The pool is managed by a controller that keeps track of memory usage and allocated memory among hosts. The controller allocates or reclaims memory between hosts, as needed by the hosts. Memory allocated from a second host to a first host may then be divided into smaller portions by the first host, and further allocated to virtual machines executing within the first host.

Abstract: Techniques for achieving application high availability via application-transparent battery-backed replication of persistent data are provided. In one set of embodiments, a computer system can detect a failure that causes an application of the computer system to stop running. In response to detecting the failure, the computer system can copy persistent data written by the application and maintained locally at the computer system to one or more remote destinations, where the copying is performed in a manner that is transparent to the application and while the computer system runs on battery power. The application can then be restarted on another computer system using the copied data.

Abstract: Techniques for achieving application high availability via crash-consistent asynchronous replication of persistent data are provided. In one set of embodiments, an application running on a computer system can, during runtime of the application: write persistent data to a local nonvolatile data store of the computer system, write one or more log entries comprising the persistent data to a local log region of the computer system, and asynchronously copy the one or more log entries to one or more remote destinations. Then, upon detecting a failure that prevents the application from continuing execution, the computer system can copy the local log region or a remaining portion thereof to the one or more remote destinations, where the copying is performed while the computer system runs on battery power and where the application is restarted on another computer system using a persistent state derived from the copied log entries.

Abstract: Techniques for achieving application high availability via application-transparent battery-backed replication of persistent data are provided. In one set of embodiments, a computer system can detect a failure that causes an application of the computer system to stop running. In response to detecting the failure, the computer system can copy persistent data written by the application and maintained locally at the computer system to one or more remote destinations, where the copying is performed in a manner that is transparent to the application and while the computer system runs on battery power. The application can then be restarted on another computer system using the copied data.

Abstract: The disclosure provides an approach for creating a pool of memory out of local memories of host machines, and providing that pool for the hosts to use. The pool is managed by a controller that keeps track of memory usage and allocated memory among hosts. The controller allocates or reclaims memory between hosts, as needed by the hosts. Memory allocated from a second host to a first host may then be divided into smaller portions by the first host, and further allocated to virtual machines executing within the first host.

Abstract: Exemplary methods, apparatuses, and systems include a distributed memory agent within a first node intercepting an operating system request to open a file from an application running on the first node. The request includes a file identifier, which the distributed memory agent transmits to a remote memory manager. The distributed memory agent receives, from the remote memory manager, a memory location within a second node for the file identifier and information to establish a remote direct memory access channel between the first node and the second node. In response to the request to open the file, the distributed memory agent establishes the remote direct memory access channel between the first node and the second node. The remote direct memory access channel allows the first node to read directly from or write directly to the memory location within the second node while bypassing an operating system of the second node.

Abstract: Exemplary methods, apparatuses, and systems include a distributed memory agent within a first node intercepting an operating system request to open a file from an application running on the first node. The request includes a file identifier, which the distributed memory agent transmits to a remote memory manager. The distributed memory agent receives, from the remote memory manager, a memory location within a second node for the file identifier and information to establish a remote direct memory access channel between the first node and the second node. In response to the request to open the file, the distributed memory agent establishes the remote direct memory access channel between the first node and the second node. The remote direct memory access channel allows the first node to read directly from or write directly to the memory location within the second node while bypassing an operating system of the second node.

Abstract: Techniques for achieving application high availability via application-transparent battery-backed replication of persistent data are provided. In one set of embodiments, a computer system can detect a failure that causes an application of the computer system to stop running. In response to detecting the failure, the computer system can copy persistent data written by the application and maintained locally at the computer system to one or more remote destinations, where the copying is performed in a manner that is transparent to the application and while the computer system runs on battery power. The application can then be restarted on another computer system using the copied data.

Abstract: Techniques for achieving application high availability via crash-consistent asynchronous replication of persistent data are provided. In one set of embodiments, an application running on a computer system can, during runtime of the application: write persistent data to a local nonvolatile data store of the computer system, write one or more log entries comprising the persistent data to a local log region of the computer system, and asynchronously copy the one or more log entries to one or more remote destinations. Then, upon detecting a failure that prevents the application from continuing execution, the computer system can copy the local log region or a remaining portion thereof to the one or more remote destinations, where the copying is performed while the computer system runs on battery power and where the application is restarted on another computer system using a persistent state derived from the copied log entries.

Abstract: According to one embodiment, a method comprises evaluating messages between nodes of a distributed computing environment. Based on timing relationships of the messages, probability of causal links between pairs of messages determined. Based on the determined probability, at least one causal path comprising a plurality of causal links is inferred. Further, an overall probability that the inferred causal path is accurate is determined. In certain embodiments, the overall probability is output for the corresponding causal path to provide an indication of the confidence of the accuracy of such inferred causal path.

Abstract: According to at least one embodiment, a method comprises identifying at least one causal path that includes a node of a distributed computing environment that is of interest. The method further comprises analyzing the identified at least one causal path to determine at least one time interval when the node is active in such causal path, and correlating consumption of a resource by the node to the node's activity in the at least one causal path.

Abstract: A method, and associated apparatus, comprises calculating a first part of a message authentication function by a first processor, calculating a second part of the message authentication function by a second processor, and combining the first and second parts into the message authentication function by the first or second processor. The message authentication function can be used to authenticate data transmitted between the first processor and a third processor.

Abstract: Method and apparatus for determining causal relations between a plurality of intercommunicating nodes. In various embodiments, trace data is input that describe inter-node communication. The trace data may include for each message sent between nodes a timestamp that indicates a time at which the message was sent, a source identifier that identifies a node from which the message was sent, and a destination identifier that identifies a node to which the message was sent. For each of one or more nodes, a determination may be made as to whether one or more causal relations exist between a first set of messages destined to the node and a second set of messages sourced from the node and destined to at least one other node. A causal relation may exist as a function of a probability distribution of delay values that are differences between timestamps of messages in the second set and timestamps of messages in the first set. From the nodes and causal relations a processor-readable representation is generated.