Vmware, Inc.

Carnegie Mellon University

Other

Xigmix, Inc.

Xin Liang Li

Pascal Renauld

Eric Shannon Knauft

Enning Xiang

Lawrence Thomas Pileggi

Wenguang Wang

Jin Zhang

Haoran Zheng

Peng Li

Bryan Fink

Yang Xu

Michael Wei

Robert W Beauchamp

Yue Li

Jian-Gang Zhu

Sandeep Rangaswamy

Yiqi Xu

Maithem Munshed

Jiayong Le

Chenggong Charles Fan

Wenbin Zhu

Mustafa Celik

Anny Martinez Manzanilla

Yi Luo

Larry Pileggi

Srinivas Aji

Venkata Ramanan

Lawrence Piileggi

The disclosure herein describes tracking changes to a stale component using a synchronization bitmap. A first component of a plurality of mirrored components of the distributed data object becomes available from an unavailable state, and a stale log sequence number (LSN) and a last committed LSN are identified. A synchronization bitmap of the first component associated with a range of LSNs (e.g., from the stale LSN to the last committed LSN) is created and configured to track changes to data blocks of the first component. A second component is identified based on the second component including a tracking bitmap associated with an LSN that matches the stale LSN of the first component. The first component is synchronized with data from the second component based on, wherein the synchronizing includes updating the synchronization bitmap to track changes made to data blocks of the first component.

Synchronizing changes to stale components of a distributed object using synchronization bitmaps

Garbage collection processing in a distributed shared log system includes a client identifying obsoleted log entries for a shared data object. The client sends information associated with the identified obsoleted log entries to a shared log server. The shared log server receives information associated with obsoleted log entries from all clients in the distributed shared log system and uses the information to delete the obsoleted log entries. The shared log server can update a snapshot mark to indicate the earliest time that a snapshot of the shared log can be taken. The snapshot mark can be updated based on the information associated with obsoleted log entries.

In-place garbage collection for state machine replication

Disclosed herein is an apparatus and method for a distributed memory object system. In one embodiment, a method includes forming a system cluster comprising a plurality of nodes, wherein each node includes a memory, a processor and a network interface to send and receive messages and data, electing a cluster manager to mediates cluster membership, node identification assignment, and a name service group, creating a node manager to initiate services for each of the plurality of nodes, wherein the node manager is configured to notify the cluster manager of its existence and node health, and creating a plurality of sharable memory spaces, wherein each space is a distributed memory object having an object owner node, and partitioning address space within each sharable memory space into chunks, wherein data may be placed in one or more memory regions mapped to the distributed memory object by either of a store call or a write call, and data stored in one or more memory regions mapped to the direct memory object may be accessed by a load call or a read call.

Distributed memory object method and system enabling memory-speed data access in a distributed environment

Example methods and systems are provided for storage reclamation from a distributed storage system in a virtualized computing environment. The method may comprise: detecting a request to reclaim a target address range associated with the distributed storage system; and mapping the target address range to multiple data chunks. The method may also comprise: in response to identifying a fully-reclaimable stripe spanning across the multiple storage resources, reclaiming particular data chunks associated with the fully-reclaimable stripe, and parity chunk(s) associated with the fully-reclaimable stripe.

Storage reclamation for distributed storage systems

A tenant's clear text data in a multi-tenant storage system can be encrypted using the tenant's cryptographic key to produce encrypted yet compressible data ('cryptographic data'). The cryptographic data can be encrypted using a system cryptographic key that is managed by the multi-tenant storage system and then stored. Use of the system cryptographic key allows for subsequent maintenance activities such as deduplication and compression to be performed on data stored in the multi-tenant storage system without having to access any of the tenants' cryptographic keys.

Multi-tenant encryption on distributed storage having deduplication and compression capability

A multi-tenant storage system can store clear text data and associated clear text checksum received from a storage tenant using their associated cryptographic key ('cryptokey'). When the clear text data is compressible, cryptographic data ('cryptodata') is generated from a concatenation of the clear text checksum and compressed clear text data using the cryptokey. A cryptographic checksum (&#x201c;cryptochecksum&#x201d;) is generated from the cryptodata. When the clear text data is uncompressible, cryptographic data (&#x201c;cryptodata&#x201d;) is generated by encrypting the clear text data using the cryptokey with an extra verification step to make sure the clear text checksum can be rebuilt during the read request. A cryptographic checksum (&#x201c;cryptochecksum&#x201d;) is generated from the cryptodata. The cryptodata and associated cryptochecksum are stored in the multi-tenant storage system, so that repairs to damaged cryptodata can be made using the associated cryptochecksum.

End-to-end checksum in a multi-tenant encryption storage system

Systems and techniques are described for transferring data. A described technique includes receiving a request to transmit a data block from a first data storage device to a second data storage device. An attempt to read the data block from the first data storage device is made. A media error resulting from the attempt to read the data block from the first data storage device is detected. In response to detecting the media error, a new data block is generated and includes mismatched checksum data that causes a checksum mismatched error when the new data block is accessed. The new data block is transmitted for storage at the second data storage device in place of the data block.

Synchronizing replicas with media errors in distributed storage systems

The invention discloses a method for tuning nano-scale analog-circuit designs in order to reduce random-device mismatches and optimize said design, where nano-scale devices potentially have large-scale process variations. The method includes providing a tunable circuit topology, wherein each nano-scale device comprises a single component or comprises multiple parallel components. Each component is decomposed into multiple discrete sub-components, wherein each said sub-component either operates in parallel with other like components to effectively operate like one bigger component. The sub-components are subjected to a dynamic-programming process to adaptively select the sub-components to be kept operational, while configuring the nonselected sub-components to be nonoperational, based on the measurement of at least one operational parameter.

Tunable integrated circuit design for nano-scale technologies

The present invention is a method and apparatus for creating a reduced-order IC interconnect model, which incorporates variations in interconnect process parameters, and models both on-chip and off-chip interconnects. The method is based on mathematically representing an IC interconnect system, including mathematical interconnect process parameter terms, which are manipulated to facilitate simplification of an IC interconnect model. The IC interconnect model is then simplified by using a mathematical technique called state-space projection. Specifically, an IC interconnect system is represented with at least one modified nodal analysis equation (MNA) that is based on frequency, interconnect process parameters are added and substituted back into the MNA(s), terms with interconnect process parameters are explicitly matched. A state-space projection is created, which implicitly matches frequency terms. The state-space projection is used to create the reduced-order IC interconnect model.

Method for parameterized model order reduction of integrated circuit interconnects

A magnetic memory or MRAM memory system comprising an M&#xd7;N crossbar array of MRAM cells. Each memory cell stores binary data bits with switchable magnetoresistive tunnel junctions (MJT) where the electrical conductance changes as the magnetic moment of one electrode (the storage layer) in the MJT switches direction. The switching of the magnetic moment is assisted by a phase transition interlayer that transitions from antiferromagnetic to ferromagnetic at a well defined, above ambient temperature.

Crossbar diode-switched magnetoresistive random access memory system

A computer implemented method of performing projection based polynomial fitting. The method includes generating a plurality of sampling points as a function of variables. The method also includes forming a polynomial model template representative of the plurality of sampling points. According to embodiments of the present invention, the polynomial model template comprises at least one polynomial coefficient. The method further includes forming a low-rank matrix to approximate the polynomial coefficient.

Statistical optimization and design method for analog and digital circuits

Analog and radio frequency system-level simulation using frequency relaxation. Embodiments of the invention use a frequency relaxation approach for analog/RF system-level simulation that accommodates both large system size and complex signal space. The simulator can determine an output response for a system by partitioning the system into blocks and simulating the propagation of an input signal through the blocks. The input signal can take various forms, including a multi-tone sinusoidal signal, a continuous spectra signal, and/or a stochastic signal. Frequency relaxation is applied to produce individual responses. The output response can be computed based on obtaining convergence of the individual responses. The input to embodiments of the simulator can be a circuit netlist, or a block-level macromodel.

Analog and radio frequency (RF) system-level simulation using frequency relaxation

The large-scale process and environmental variations for today's nano-scale ICs are requiring statistical approaches for timing analysis and optimization (). Significant research has been recently focused on developing new statistical timing analysis algorithms (), but often without consideration for how one should interpret the statistical timing results for optimization. The invention provides a sensitivity-based metric () to assess the criticality of each path and/or arc in the statistical timing graph (). The statistical sensitivities for both paths and arcs are defined. It is shown that path sensitivity is equivalent to the probability that a path is critical, and arc sensitivity is equivalent to the probability that an arc sits on the critical path. An efficient algorithm with incremental analysis capability () is described for fast sensitivity computation that has a linear runtime complexity in circuit size. The efficacy of the proposed sensitivity analysis is demonstrated on both standard benchmark circuits and large industry examples.

Defining statistical sensitivity for timing optimization of logic circuits with large-scale process and environmental variations

An auxiliary frame for detachably mounting in front of a spectacle frame includes a mounting frame and a retention arrangement. The mounting frame supports two shelter lenses for detachably mounting on a spectacle bridge. The retention arrangement includes two guiding members and two urging members. The two guiding members are rearwardly extended from two inner sides of the shelter lenses respectively and defined a guiding distance between the two guiding members which is smaller than the lens distance of the spectacle frame. The two urging members define an urging distance which is larger than the lens distance of the spectacle frame, such that when the guiding members are extended at the two inner sides of the spectacle lens respectively, the two urging members are adapted for applying an urging force against the two inner sides of the spectacle lens respectively.

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Pomona, CA, United States of America

Xin Liang Li