Communication performance between two processes in their own domains on the same physical machine gets improved but it does not reach our expectation. This paper presents the design and implementation of high-performance inter-domain communication mechanism, called XWAY, that maintains binary compatibility for applications written in standard socket interface. As a result of our survey, we found that three overheads mainly contribute to the poor performance; those are TCP/IP processing cost in each domain, page flipping overhead, and long communication path between both sides of a socket. XWAY achieves high performance by bypassing TCP/IP stacks, avoiding page flipping overhead, and providing a direct, accelerated communication path between domains in the same machine. Moreover, we introduce the XWAY socket architecture to support full binary compatibility with as little effort as possible.

The EXT3NS is a scalable file system designed to handle video streaming workload in large-scale on-demand streaming services. It is based on a special H/W device, called Network-Storage card (NS card), which aims at accelerating streaming operation by shortening the data path from storage device to network interface. The design objective of EXT3NS is to minimize the delay and the delay variance of I/O request in the sequential workload on NS card. Metadata structure, file organization, metadata structure, unit of storage, etc. are elaborately tailored to achieve this objective. Further, EXT3NS provides the standard API's to read and write files in storage unit of NS card. The streaming server utilizes it to gain high disk I/O bandwidth, to avoid unnecessary memory copies on the data path from disk to network, and to alleviates CPU's burden by offloading parts of network protocol processing, The EXT3NS is a full functional file system based on the popular EXT3. The performance measurements on our prototype video server show obvious performance improvements. Specifically, we obtain better results from file system benchmark program, and obtain performance improvements in disk read and network transmission, which leads to overall streaming performance increase. Especially, the streaming server shows much less server's CPU utilization and less fluctuation of client bit rate, hence more reliable streaming service is possible.

Abstract The Virtual Interface Architecture (VIA) is an industry standard user‐level communication architecture for system area networks. The VIA provides a protected, directly‐accessible interface to a network hardware, removing the operating system from the critical communication path. In this paper, we design and implement a user‐level Sockets layer over VIA, named SOVIA (Sockets Over VIA). Our objective is to use the SOVIA layer to accelerate the existing Sockets‐based applications with a reasonable effort and to provide a portable and high‐performance communication library based on VIA to application developers. SOVIA realizes comparable performance to native VIA, showing a minimum one‐way latency of 10.5 $\mu$ s and a peak bandwidth of 814 Mbps on Giganet's cLAN. We have shown the functional compatibility with the existing Sockets API by porting File Transfer Protocol (FTP) and Remote Procedure Call (RPC) applications over the SOVIA layer. Compared to the Giganet's LAN Emulation (LANE) driver which emulates TCP/IP inside the kernel, SOVIA easily doubles the file transfer bandwidth in FTP and reduces the latency of calling an empty remote procedure by 77% in RPC applications. Copyright © 2003 John Wiley & Sons, Ltd.

The Virtual Interface Architecture (VIA) is an industry standard user-level communication architecture for system area networks. The VIA provides a protected, directly-accessible interface to a network hardware, removing the operating system from the critical communication path. In this paper, we design and implement a user-level Sockets layer over VIA, named SOVIA (Sockets Over VIA). Our ob-jective is to use the SOVIA layer to accelerate the existing Sockets-based applications with a reasonable effort and to provide a portable and high performance communication library based on VIA to the application developers. SOVIA realizes comparable performance to native VIA, showing the minimum latency of 10.5sec and the peak bandwidth of 814Mbps on Giganet’s cLAN. We have ver-ified the functional compatibility with the existing Sockets API by porting FTP (File Transfer Protocol) and RPC (Re-mote Procedure Call) applications over the SOVIA layer. Compared to the Giganet’s LANE driver which emulates TCP/IP inside the kernel, SOVIA easily doubles the file transfer bandwidth in FTP and reduces the latency of call-ing an empty remote procedure by 77 % in RPC applica-tions. 1.

The Virtual Interface Architecture (VIA) is an industry standard user-level communication architecture for cluster or system area networks. The VIA provides a protected, directly-accessible interface to a network hardware, removing the operating system from the critical communication path. Although the VIA enables low-latency high-bandwidth communication, the application programming interface defined in the VIA specification lacks many high-level features.