The invention relates to a method for providing a fault-tolerant global time via a time server in a distributed real-time computer system, wherein the time server comprises four components which are connected to one another via a bi-directional communication channel. At a priori defined periodic, internal synchronization times, each of the four components transmits an internal synchronization message, which is simultaneously transmitted to the other three components, from which each internal computer of a component determines a correction term for the tick counter contained in its component and corrects the reading of the local tick counter by this correction term.

Examples include a method of live migrating a virtual device by creating a virtual device in a virtual machine, creating first and second interfaces for the virtual device, transferring data over the first interface, detecting a disconnection of the virtual device from the virtual machine, switching data transfers for the virtual device from the first interface to the second interface, detecting a reconnection of the virtual device to the virtual machine, and switching data transfers for the virtual device from the second interface to the first interface.

Systems, methods, apparatuses, and software for data storage systems are provided herein. In one example, a data storage system is provided that includes storage drives each comprising a PCIe interface, and configured to store data and retrieve the data stored on associated storage media responsive to data transactions received over a switched PCIe fabric. The data storage system includes processors configured to each manage only an associated subset of the storage drives over the switched PCIe fabric. A first processor is configured to identify first data packets received over a network interface associated with the first processor within a network buffer of the first processor as comprising a storage operation associated with at least one of the plurality of storage drives managed by a second processor, and responsively transfer the first data packets into a network buffer of the second processor.

Methods and systems for managing sets of transactions for replication are provided. A system includes a number of origination nodes forming a source array. A sequence number generator generates sequence numbers based, at least in part, on a time interval during which a transaction is received. A subset manager groups transactions into subsets based, at least in part, on the sequence number.

Methods and systems for collision handling during an asynchronous replication are provided. A system includes a cache memory system comprising a number of cache memory pages. A collision detector detects when a host is attempting to overwrite a cache memory page that has not been completely replicated. A revision page tagger copies the cache memory page to a free page and tags the copied page as protected.

A method for performing initial registration is provided. The method includes receiving a server timeout message, the server timeout message including at least a field set to a value equal to a value received during a first registration. The method further includes initiating restoration procedures by performing an initial registration.

The present disclosure relates to a method of operating a database system. The database system comprises: a database; a first compute node comprising a first database proxy; and a second compute node comprising a second database proxy. The method comprises receiving and processing, at the first database proxy, a first plurality of access requests to access the database; receiving and processing, at the second database proxy, a second plurality of database access requests to access the database; monitoring for a failure event associated with the first database proxy; and, in response to the monitoring indicating a failure event, initiating a failover procedure between the first database proxy and the second database proxy. The failover procedure comprises: redirecting the first plurality of access requests to the second database proxy; and processing, at the second database proxy, the first plurality of access requests.

A cluster system including a plurality of nodes, a plurality of clusters included in each node and a management module managing the cluster system and an arithmetic module, which are included in each of the clusters, wherein, among all the management modules included in the cluster system, one management module is set representative management module, in the individual clusters, one is set as a master management module, and another is set as a standby management module. Each of the management modules includes a failure monitoring unit and a failover control unit. When a failure in the representative management module is detected by any of the failure monitoring units, any of the management modules included in the non-representative management modules, is set as a new representative management module. A recovery unit restores the failure monitoring unit and the failover control unit in the management module in which a failure is detected.

A host computing device includes a host processor, host memory in electronic communication with the host processor, and an auxiliary service controller. The host computing device also includes a communication interface and a messaging interface between the host processor and the auxiliary service controller. A message handler is stored in the host memory. The message handler is executable by the host processor in response to detecting a messaging interface signal on the messaging interface. Execution of the message handler by the host processor causes a firmware update patch to be read from a shared memory region in the auxiliary service controller via the communication interface.

Provided are a computer program product, system, and method for using a track format code in a cache control block for a track in a cache to process read and write requests to the track in the cache. A track format table associates track format codes with track format metadata. A determination is made as to whether the track format table has track format metadata matching track format metadata of a track staged into the cache. A determination is made as to whether a track format code from the track format table for the track format metadata in the track format table matches the track format metadata of the track staged. A cache control block for the track being added to the cache is generated including the determined track format code when the track format table has the matching track format metadata.