光纤通道SOPC系统性能优化设计技术研究

Study on Optimization Design Technique of Fibre Channel SOPC System Performance

针对光纤通道(Fibre Channel,FC)片上可编程系统(SOPC)中制约传输速度的关键环节,从4个层面进行了性能优化设计:使用离散集中式直接存储器访问(Scatter-Gather Direct Memory Access,SGDMA)代替传统的DMA进行高效的数据搬运;扩展Fibre Channel协议硬件模块数据缓冲区以实现多帧传输;在Power PC固件中设计新的内存管理队列以避免内存碎片;分配特定的非缓存内存区域以保证缓存的一致性及有效性。对比测试实验表明:系统优化后数据传输速度从39 MB/s提高到115 MB/s。

Aiming at the key items restricting data transmission rate in the System On Programmable Chip（SOPC） of Fiber Channel （FC） ,four methods for improving the performance of fiber channel system are proposed in this paper. First, Scatter-Gather Direct Memory Access（SGDMA） is adopted to replace the traditional DMA to increase data transmission rate.Second,buffers in the hardware interface of fiber channel protocol are developed to allow transmission for multiple frames. Third, an optimized memory management queue is designed to avoid memory fragmentations. Finally, the cache coherence problem is solved by allocating specific non-cache memory areas to utilize the high-speed caches effectively.The comparison test experiments show that the transmission rate increases from 39MB/s to 115MB/s after optimization.