Eflops,Zflops芯片挑战.ppt

* The major resources we are concerned in computer and distributed systems are: * The major resources we are concerned in computer and distributed systems are: * 2.5 As we know, disk I/O performance is critical to data-intensive applications. This is because these applications demand efficient I/O support. For example, database systems can manage millions of records on a storage device and access them in either small or large pieces, which requires low access time or high transfer rate of storage devices. For multimedia applications, they often access large blocks of data in a predictable sequence and demand a guaranteed minimal transfer rate. For scientific applications, I/O can be a big challenge because a huge amount of data can be requested in very-large-scale parallel systems within a short time. At Los Alamos national lab, ASCI mission-oriented programs conducts large-scale simulation-based analysis, which requires several gigabytes per second I/O bandwidth to support physical simulation and visualization. Their access granularity can be coarse or fine, and the access patterns can be predictable or random. For other relatively small-scale desktop applications such as CVS and grep, they also exhibit various access granularity and access patterns. These applications run on various computer configurations, from workstations, distributed systems, to large-scale parallel systems. At both extremes the ubiquitous hard disk remains the most cost-effective on-line storage device. A disk can be used individually, or multiple disks form into a disk array. For large systems, disks can be interconnected into NAS (Network Attached Storage) or SAN (Storage Area Network). * However, all proposed schemes were evaluated by simulation, there are several limitations in simulation-based study: First, the simulation time is extremely long, for example, it would take several weeks or months to complete a single SPEC CPU2006 application. As the number of cores continues to