There are provided an information processing system that operates virtual machines and storage controllers on a processor, and an information processing method executed by the information processing system. A storage controller group capable of taking over processing between the storage controllers arranged in different nodes is provided. The virtual machine is movable between the different nodes by deploy. The virtual machine and the storage controller that processes data input and output by the virtual machine are arranged in the same node. A combination of the virtual machines that cannot be arranged in the same node is defined by a restriction. A management unit arranges one of the virtual machines that cannot be arranged in the same node in the node in which the storage controller included in the storage controller group to which the storage controller used by the other virtual machine belongs is not arranged.

This application discloses an arbitration method and a related apparatus. The method includes: detecting, by the first ABS apparatus, first status information of a service module in the first DC; when determining that a communication link between the first DC and the second DC is faulty, obtaining, by the first ABS apparatus, second status information, wherein the second status information is status information that is of a service module in the second DC and that is detected by the second ABS apparatus; and arbitrating, by the first ABS apparatus, a subsequent service providing capability of the first DC based on the first status information and the second status information.

Disclosed are various embodiments for distributing data items within a plurality of nodes. A data item that is subject to a data item update request is updated from a master node to a plurality of slave notes. The update of the data item is determined to be locality-based durable based at least in part on acknowledgements received from the slave nodes. Upon detection that the master node has failed, a new master candidate is determined via an election among the plurality of slave nodes.

A computing system that enables data stored in a persistent memory region to be preserved when a processor fails can include volatile memory comprising the persistent memory region, non-volatile memory, and a system on a chip (SoC). The SoC can include a main processor that is communicatively coupled to both the volatile memory and the non-volatile memory. The SoC can also include an auxiliary processor that is communicatively coupled to both the volatile memory and the non-volatile memory. The SoC can also include instructions that are executable by the auxiliary processor to cause the data in the persistent memory region of the volatile memory to be transferred to the non-volatile memory in response to a failure of the main processor.

A fault tolerant computer system and method are disclosed. The system may include a plurality of CPU nodes, each including: a processor and a memory; at least two IO domains, wherein at least one of the IO domains is designated an active IO domain performing communication functions for the active CPU nodes; and a switching fabric connecting each CPU node to each IO domain. One CPU node is designated a standby CPU node and the remainder are designated as active CPU nodes. If a failure, a beginning of a failure, or a predicted failure occurs in an active node, the state and memory of the active CPU node are transferred to the standby CPU node which becomes the new active CPU node. If a failure occurs in an active IO domain, the communication functions performed by the failing active IO domain are transferred to the other IO domain.

A distributed system for creating a checkpoint for a plurality of processes running on the distributed system. The distributed system includes a plurality of compute nodes with an operating system executing on each compute node. A checkpoint library resides at the user level on each of the compute nodes, and the checkpoint library is transparent to the operating system residing on the same compute node and to the other compute nodes. Each checkpoint library uses a windowed messaging logging protocol for checkpointing of the distributed system. Processes participating in a distributed computation on the distributed system may be migrated from one compute node to another compute node in the distributed system by re-mapping of hardware addresses using the checkpoint library.

An illustrative report server interoperates with one or more enhanced storage managers to evaluate whether backup operations and restore operations meet their recovery point objectives (RPO) and recovery time objectives (RTO), respectively. RTO is evaluated using a tiered approach based on past performance of restore and/or backup operations. The illustrative storage manager executes pre-defined queries that extract relevant information from an associated database that houses information about storage operations. The report server recommends alternative kinds of backup operations for data that fails to meet its RTO using traditional backups. The report server is configured to analyze and report RPO and RTO readiness for several levels of data entities, including multiple systems, single system, groups of clients, single clients, and subclients.

A dynamic feedback technique improves data replication performance by balancing rates of data retrieval and data transmission of a fragmented virtual disk replicated between nodes of clusters on a local site and a remote site of a disaster recovery environment. Each node is embodied as a physical computer with hardware resources, such as processor, memory, network and storage resources, which are virtualized to provide support for one or more user virtual machines executing on the node. The storage resources include storage devices of an extent store, whereas the network includes a wide area network connecting the local and remote sites. The dynamic feedback technique employs a virtual memory buffer configured to balance the data storage retrieval and network transmission rates at a source of replication based on bandwidth demands of the extent store and network throughput as manifested by an available free space (i.e., emptiness) of the virtual buffer.

In a storage system architecture having two storage virtualization controllers (SVCs) that operate in an active-active mode, the corresponding relationships between storage addresses in the two buffers of the two SVCs are pre-determined. When a non-owner SVC that does not have an ownership over a logical disk (LD), receives an I/O request from a host, the non-owner SVC will inquire of the other SVC having the ownership, about associated address information, and then the non-owner SVC that does not have the ownership over the LD will perform, according to the associated address information, the I/O request from the host. Therefore, data synchronization operation for mutually backing up data between the two SVCs can be fast achieved. Also, it allows the host to issue a data access request to any one of the SVCs, thus improving performance of the storage system.

Each redundancy group is constituted by one active program (storage control software of the active program) and N standby programs (N is an integer of two or more). Each of the N standby programs is associated with a priority to be determined as a failover (FO) destination. In the same redundancy group, FO is performed from the active program to the standby program based on the priority. For the plurality of pieces of storage control software including the active programs and the standby programs that change to be active by FO in the plurality of redundancy groups arranged in the same node, standby storage control software that can set each of the programs as a FO destination are arranged in different nodes.