Oracle International Corporation

Navaneeth P Jamadagni

Ivan E Sutherland

Josephus Ebergen

Mark Semmelmeyer

Anatoly Yakovlev

Guanghua Shu

Ji Eun Jang

Vincent Lee

Craig Schelp

Arun Raghavan

Paria Rashidinejad

Charles Gordon

An apparatus includes a first device having a clock signal and configured to communicate, via a data bus, with a second device configured to assert a data strobe signal and a plurality of data bit signals on the data bus. The first device may include a control circuit configured, during a training phase, to determine relative timing between the clock signal, the plurality of data bit signals, and the data strobe signal. The first device may determine, using a first set of sampling operations, a first timing relationship of the plurality of data bit signals relative to the data strobe signal, and determine, using a second set of sampling operations, a second timing relationship of the plurality of data bit signals and the data strobe signal relative to the clock signal. During an operational phase, the control circuit may be configured to use delays based on the first and second timing relationships to sample data from the second device on the data bus.

Method for training multichannel data receiver timing

Techniques are described herein for accurately measuring the reliability of storage systems. Rather than relying on a series of approximations, which may produce highly optimistic estimates, the techniques described herein use a failure distribution derived from a disk failure data set to derive reliability metrics such as mean time to data loss (MTTDL) and annual durability. A new framework for modeling storage system dynamics is described herein. The framework facilitates theoretical analysis of the reliability. The model described herein captures the complex structure of storage systems considering their configuration, dynamics, and operation. Given this model, a simulation-free analytical solution to the commonly used reliability metrics is derived. The model may also be used to analyze the long-term reliability behavior of storage systems.

Techniques for accurately estimating the reliability of storage systems

The disclosed embodiments disclose techniques for performing quotient selection in an iterative carry-save division operation that divides a dividend, R, by a divisor, D, to produce an approximation of a quotient, Q=R/D. During a divide operation, a divider approximates Q by iteratively selecting an operation to perform for each iteration of the carry-save division operation and then performing the selected operation. The operation for each iteration is selected based on the current partial sum bits of a partial remainder in carry-save form (rs) and the current partial carry bits of a partial remainder in carry-save form (rc). More specifically, the operation is selected from a set of operations that includes: (1) a 2X* operation; (2) an S1 & 2X* operation; (3) an S2 & 2X* operation; (4) an A1 & 2X* operation; and (5) an A2 & 2X* operation.

Performing quotient selection for a carry-save division operation

The disclosed embodiments disclose techniques for using a split division circuit that includes a first divider that is optimized for a first range of divisor values and a second divider that is optimized for a second range of divisor values; the first range is distinct from the second range. During operation, the circuit receives a divisor for the division operation. The circuit: determines whether the divisor is in the first range or the second range to determine whether the first divider or the second divider should perform the division operation; performs the division operation in the selected host divider; and then outputs the result that was generated by the selected host divider.

Performing a division operation using a split division circuit

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San Francisco, CA, United States of America

Navaneeth P Jamadagni