Optimization of the image cache throughput for a large-scale PACS archive

With the increasing number of PACS image display workstations deployed in clinical operations, a PACS image server needs to be tuned more effectively to achieve optimal system throughput. There are many factors that affect the performance of image transfer, including the application software program, the storage subsystem, and the network system. This paper primarily addresses the issues involving the image storage subsystem. Related research has been done to address the issues in network system and application software. One primary factor that affects the overall performance of a PACS image server is the throughput and reliability characteristics of the magnetic storage devices for image caching. A redundant array of inexpensive disks (RAID) is a mean to provide reliable and high performance storage. The UCLA PACS image server relies on a software-based RAID system to fulfill the bandwidth requirement and reliability demand. An extensive evaluation on various hardware and software parameters in the I/O subsystem has been conducted to derive an optimal configuration, which specifically attempts to address the following questions: How many disks should be in a stripe group? What is the optimal stripe chunk size? How big should the maxcontig be? What should be the IO request size? And how many concurrent I/O accesses should be allowed?© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.