Abstract:
A block-based storage system may implement dynamic durability adjustment for page cache write logging. A rate of incoming write requests for data volumes maintained at a storage node may be monitored. Based, at least in part, on the rate of incoming write requests, a dynamic modification to a durability property for a data volume may be made, such as enabling page cache write logging the data volume or disabling write logging for the data volume. When incoming write requests are received, a determination may be made as to whether page cache write logging for a particular data volume is enabled. For write requests with disabled page cache write logging, the page cache may be updated and the write request may be acknowledged without storing a log record describing the update in a page cache write log.
Abstract:
Embodiments of the present invention provide an adaptive cache system and an adaptive cache system for a hybrid storage system. Specifically, in a typical embodiment, an input/out (I/O) traffic analysis component is provided for monitoring data traffic and providing a traffic analysis based thereon. An adaptive cache algorithm component is coupled to the I/O traffic analysis component for applying a set of algorithms to determine a storage schema for handling the data traffic. Further, an adaptive cache policy component is coupled to the adaptive cache algorithm component. The adaptive cache policy component applies a set of caching policies and makes storage determinations based on the traffic analysis and the storage schema. Based on the storage determinations, data traffic can be stored (e.g., cached) among a set of storage devices coupled to the adaptive cache policy component. Such storage components can include: a low-mid-high cache solution, a low speed storage component (e.g., a high density drive (HDD), flash memory unit, etc.), a middle speed storage component (PRAM, FRAM, MRAM SSD, etc.), and a high speed storage component (e.g., a DRAM SSD). The high speed storage component itself can comprise a cache area, a high speed storage area, and a storage manager.
Abstract:
A method and system to provide an analysis model to determine the specific problem(s) of a multi-threaded application. In one embodiment of the invention, the multi-thread application uses a plurality of threads for execution and each thread is assigned to a respective one of a plurality of states based on a current state of each thread. By doing so, the specific problem(s) of the multi-threaded application is determined based on the number of transitions among the plurality of states for each thread. In one embodiment of the invention, the analysis model uses worker threads transition counters or events to determine for each parallel region or algorithm of the multi-threaded application which problem has happened and how much it has affected the scalability of the parallel region or algorithm.
Abstract:
An efficient, cycle-accurate processor execution simulator models a target processor by executing a program execution image comprising instructions having run-time dependencies resolved by execution on an existing processor compatible with the target processor. The instructions may have been executed upon a processor in an I/O environment too complex to model. In one embodiment, the simulator executes instructions that were directly executed on a processor. In another embodiment, a markup engine alters a compiled program image, with reference to instructions executed on a processor, to remove run-time dependencies. The marked up program image is then executed by the simulator. The processor execution simulator includes an update engine operative to cycle-accurately simulate instruction execution, and a communication engine operative to model each communication bus of the target processor.
Abstract:
A system comprises a processor and an alert module coupled to the processor. The processor the processor monitors performance data; determines a subset of the performance data, the subset correlated with a measure of underperformance; determines a trend of the subset, the trend correlated with the measure; and identifies an occurrence of the trend. The alert module outputs an alert based on the identification.