Oracle International Corporation

Daniel E O'Shaughnessy

Richard L Frank

Michael J Cusson

Joydip Kundu

Gopalan Arun

A method and system provides a requested memory to a requesting process. The memory is requested by a consumer process residing in application space. The consumer process requests the requested memory from a Very Large Memory (VLM) driver in the operating system. The size of the requested memory may be larger than the maximum size per process supported by the operating system. The VLM driver creates one or more donor processes residing in application space dependent on the size of the requested memory. Each donor process requests an allocation of a portion of memory less than the maximum size per process supported by the operating system. Having received the requested memory, the donor process transfers ownership of the portion of memory to the VLM driver. The VLM driver provides the requested memory provided by the donor processes to the consumer process.

System for extending an addressable range of memory

A quorumless network cluster provides a highly available system by addressing the partition-in-space and partition-in-time problems in network clusters. In a particular solution, a cluster manager (CM) can use disk based messaging to manage the operation of the cluster. Each node within the cluster must have access to a shared disk to operate within the cluster. A particular methodology can operate the cluster in a closed loop between nodesto N. If a node fails to receive a heartbeat message from its predecessor in the loop, it initiates a cluster reconfiguration by sending a reconfiguration message to each other node in the cluster. The quorumless cluster can also include a common storage for a cluster definition. Each node may provide a proposed change to the cluster definition, however only a single coordinator node may update the cluster definition and apply the suggested changes.

Providing figure of merit vote from application executing on a partitioned cluster

Using a cluster-wide shared repository to provide the latest consistent definition of the cluster (avoiding the partition-in time problem)

A quorumless network cluster provides a highly available system by addressing the partition-in-space and partition-in-time problems in network clusters. In a particular solution, a cluster manager (CM) can use disk based messaging to manage the operation of the cluster. Each node within the cluster must have access to a shared disk to operate within the cluster. A particular methodology can operate the cluster in a closed loop between nodes 1 to N. If a node fails to receive a heartbeat message from its predecessor in the loop, it initiates a cluster reconfiguration by sending a reconfiguration message to each other node in the cluster.

Quorumless cluster using disk-based messaging

Closed-loop node membership monitor for network clusters

A method for maintaining virtual memory consistency in a multi-processor environment comprises allocating a subset of virtual memory to a process, and mapping the subset of virtual memory to a first subset of physical memory. A translator lookaside buffer (TLB) is maintained in each processor, each TLB comprising a plurality of TLB entries. Each TLB entry represents a mapping between a virtual address in the subset of virtual memory and a physical address in the first subset of physical memory. When the subset of virtual memory is to be unmapped, a reference to the first subset of physical memory is placed into a free list, and marked as dirty. When the number of dirty references exceeds a predetermined threshold, the corresponding entries in each processor's TLB are invalidated. Alternatively, all TLB entries can be invalidated. The free list comprises a plurality of free list entries, where each entry comprises a reference to virtual memory which is either unmapped or whose mapping is dirty.

Growing community of inventors

Hollis, NH, United States of America

Daniel E O'Shaughnessy