Stratus Technologies Ireland Ltd.

Stratus Technologies Bermuda Ltd.

Stratus Technologies, Inc

Lei Cao

Steven Michael Haid

Charles J Horvath

Stephen J Wark

Angel L Pagan

Nathaniel Horwitch Dailey

John Rogers MacLeod

Aaron Tyrone Smith

Michael Egan

Wendy J McNaughton

Beverly Brown

John Macleod

Charles Horvath

In part, in one aspect, the disclosure relates to a first computer system including a first processor and first memory, a first IO storage subsystem including a first switch configured for one or more first storage devices, a first IO non-storage subsystem including a first which configured for one or more first non-storage devices, a second compute system including a second processor and second memory, a second storage IO subsystem including a second switch configured for one or more second storage devices, a second IO non-storage subsystem including a second switch configured for one or more second non-storage devices and a midplane including a power connector, a processor side and an IO side, wherein the processing side includes connectors in electrical communication with the computer systems, the IO side includes connectors in electrical communication with the storage and non-storage subsystems.

Cost reduced high reliability fault tolerant computer architecture

In part, disclosure relates to a method of regulating checkpointing in an active active fault tolerant system. The method includes receiving a request from a client through a network at a primary computer; copying, by the primary computer, the request from the client to a secondary computer; processing the request from the client, using the primary computer, to generate a primary computer result; processing the copy of the request from the client, using the secondary computer, to generate a secondary computer result; comparing the primary computer result and the secondary computer result to obtain a comparison metric; determining whether a minimum checkpoint interval has been met or exceeded; and if the minimum checkpoint interval has not been met or exceeded, delay initiating a checkpoint process from primary computer to secondary computer.

Fault tolerant systems and methods incorporating a minimum checkpoint interval

A method and apparatus of performing fault tolerance in a fault tolerant computer system comprising: a primary node having a primary node processor; a secondary node having a secondary node processor, each node further comprising a respective memory; a respective checkpoint shim; each of the primary and secondary node further comprising: a respective non-virtual operating system (OS), the non-virtual OS comprising a respective; network driver; storage driver; and checkpoint engine; the method comprising the steps of: acting upon a request from a client by the respective OS of the primary and the secondary node, comparing the result obtained by the OS of the primary node and the secondary node by the network driver of the primary node for similarity, and if the comparison of indicates similarity less than a predetermined amount, the primary node network driver informs the primary node checkpoint engine to begin a checkpoint process.

Operating system-based systems and method of achieving fault tolerance

In part, the disclosure relates to a real-time fault tolerant system. The system may include a first computing device, a second computing, and a hardware interconnect. The first computing device may include one or more memory devices, one or more processors, a first network interface operable to receive device data and transmit output data over a time-slot-based bus, wherein the output data is generated from processing device data, and a first real-time checkpoint engine. The second computing device may include similar components or the same components as the first computing device. The hardware interconnect is operable to permit data exchange between the first computing device and the second computing device. Checkpoints may be generated by checkpoint engines during lower-priority communication time slots allocated on the time slot-based bus to avoid interfering with any real-time communications to or from the first and second computing devices.

Real-time fault-tolerant checkpointing

A checkpointing method in a network device fault tolerant system using virtual machines. In one embodiment, the network device has an input port, an output port, an active virtual machine and a standby virtual machine, a network application on the active virtual machine which manipulates data present on the input port and transmits the manipulated data from the output port; a checkpoint engine on the active virtual machine; and an interface agent, on the active virtual machine, having callable functions to move data from the input port to the output port. The method includes the steps of determining, by the checkpoint engine, that a checkpoint is required; requesting by the checkpoint engine that the interface agent quiescent itself; returning, by the interface agent to the network application, an indicator that no packets are available regardless of whether or not packets are arriving at the input port.

Method and apparatus for performing checkpointing on a network device

A HA computer system is configured to support the operation of an active and a standby virtual machine, and the active virtual machine supports one or more first computer processes and the standby virtual machines supports duplicates of the one or more first computer processes. Each active virtual machine monitors and stores a state of the first computer processes and periodically pauses to only synchronize some of the state of the first computer processes running on the active VM with state associated with the duplicate processes running on the standby VM stored in a first region of virtual memory.

Growing community of inventors

Westford, MA, United States of America

Lei Cao