A data storage system includes multiple head nodes and data storage sleds. Volume data is replicated between a primary and one or more secondary head nodes for a volume partition and is further flushed to a set of mass storage devices of the data storage sleds. Volume metadata is maintained in a primary and one or more secondary head nodes for a volume partition and is updated in response to volume data being flushed to the data storage sleds. Also, the primary and secondary head nodes store check-points of volume metadata to the data storage sleds, wherein in response to a failure of a primary or secondary head node for a volume partition, a replacement secondary head node for the volume partition recreates a secondary replica for the volume partition based, at least in part, on a stored volume metadata checkpoint.

Methods, systems, and apparatuses, including computer programs encoded on computer-readable media, for receiving from responders conversation selection criteria and mode of communication information. A request for a conversation is received, from an initiator using a first communication mode that identifies a topic, but does not identify any responders. A conversation identifier is created. Possible responders are determined based on the topic and the conversation selection criteria. The topic of the conversation is sent to the possible responders, without identifying the initiator. A first response from a first responder is received using a second communication mode that is different than the first communication mode. The first response is mapped to the conversation based in part on the conversation identifier. The response is sent to the initiator using the first communication mode.

A semiconductor device is provided with normal memory cells constituted so as to store user data, reference memory cells constituted so as to generate a reference signal for reading out the normal memory cells, and a control circuit that carries out a defect detecting operation for detecting whether or not the reference memory cell and data stored in the reference memory cell are coincident with expected values on the stored data read out from the reference memory cells. Moreover, it is also provided with a control circuit for executing a defect correcting operation for correcting data to be stored in the reference memory cells that are detected as defective. Furthermore, it is also provided with a control circuit that is configured so as to cut off the reference memory cell detected as defective from the sense amplifier.

The disclosed computer-implemented method for performing node failovers may include: (1) initiating, during a failover of a first node to a second node, a grace period for the first node and the second node; (2) writing a new lock, indicating an internet protocol (IP) address, to a memory device of the second node, while maintaining: (A) an old lock of the IP address in a memory device of the first node, and (B) locks of nodes other than the first and second nodes; (3) transferring the old lock from the first node to the new lock of the second node, where requests to change the locks of nodes other than the first and second nodes are denied during transferring; and (4) stopping the grace period. Various other methods, systems, and computer-readable media are also disclosed.

Techniques involve managing a storage system. In accordance with the techniques, a plurality of copies of metadata of the storage system are read from a plurality of storage devices in a resource pool of the storage system. The resource pool includes a first number of storage devices, and the metadata describes configuration information of the storage system. A second number of copies are selected from the plurality of copies based on version information in the plurality of copies, where the second number of copies comprises the metadata in the same version. It is determined whether a relation between the first number and the second number satisfies a predetermined condition. The second number of copies are identified as trusted metadata based on determining the relation satisfies the predetermined condition. With the foregoing example implementation, the metadata in the storage system may be managed with higher reliability.

A method is performed at an electronic device that includes magnetic random access memory (MRAM). The method includes loading the MRAM with data including main data, first error correcting data, and second error correcting data. The MRAM comprises a plurality of MRAM cells characterized by a first magnetic anisotropy corresponding to a first error rate at a predefined temperature that exceeds a threshold for correcting errors using only the first error correcting data. The method further includes, after loading the MRAM with the data, heating the MRAM to the predefined temperature and correcting errors in the main data using both the first error correcting data and the second error correcting data. The method further includes after correcting the errors in the main data, erasing, from the MRAM, the second error correcting data and maintaining, on the MRAM, the first error correcting data.

A computing device includes an interface configured to interface and communicate with a dispersed storage network (DSN), a memory that stores operational instructions, and a processing module operably coupled to the interface and memory such that the processing module, when operable within the computing device based on the operational instructions, is configured to perform various operations. Based on a detected storage error, the computing device is configured to determine availability status of encoded data slices (EDSs) within a set of EDSs. When at least a threshold number of EDSs are available, the computing device is configured to initiate a rebuilding function to abate the detected storage error. When less than the threshold number of EDSs are available, the computing device is configured to initiate a slice repair function to at least one storage unit (SU) to abate the detected storage error.

An access request processing method is performed by a computer device that includes a processor, a dynamic random-access memory (DRAM), and a non-volatile memory (NVM). When receiving a write request, the processor may identify an object cache page according to the write request. The processor obtains the to-be-written data from a buffer according to a buffer pointer in the write request, the to-be-written data including a new data chunk to be written into the object cache page. The processor then inserts a new data node into a log chain of the object cache page, where the NVM stores data representing the log chain of the object cache page. The new data node includes information regarding the new data chunk of the object cache page. The computer device provided in this application can reduce system overheads while protecting data consistency.

Exemplary methods, apparatuses, and systems include determining that data in a group of memory cells of a first memory device is to be moved to a spare group of memory cells. The group of memory cells spans a first dimension and a second dimension that is orthogonal to the first dimension and the spare group of memory cells also spans the first dimension and the second dimension. The data is read from the group of memory cells along the first dimension of the group of memory cells. The data is written to the spare group of memory cells along the second dimension of the spare group of memory cells.

A computer system includes a BMC and a host of the BMC. The BMC redirect, through a BMC communication channel, a local media including a disk management tool to a host of the BMC as a particular drive. The host is a storage device connected to one or more storage drives. The disk management tool is configured to prepare a storage area of the one or more storage drives for installation of storage service on the host. The storage service managing a RDMA controller at the host. The BMC configures the host to boot from the particular drive. The BMC sends a first instruction to the host instructing the BMC to reboot. The BMC receives from the host a command for reading the disk management tool. The BMC sends the disk management tool to the host.