国产飞腾1500A处理器的显存管理优化  

Video Memory Management Optimization of Domestic Phytium 1500A Processor

作　　者：孙立明[1] 吴庆波[1] 

机构地区：[1]国防科技大学计算机学院,湖南长沙410073

出　　处：《计算机技术与发展》2017年第5期6-9,共4页Computer Technology and Development

基　　金：国家"863"高技术发展计划项目(2013AA01A212)

摘　　要：基于飞腾1500A处理器的计算机系统中,现有操作系统图形子系统主存和显卡VRAM(显存)之间拷贝图形运算数据时会产生段错误,导致图形子系统只能使用主存作为显存而不能直接使用VRAM。由于显卡访问主存比访问VRAM的速度慢很多,因此在某些场景下限制了显卡的工作效率,从而限制了图形子系统的性能。为此,提出了一种基于飞腾1500A处理器的图形系统显存管理的优化方法,让图形子系统能够访问显卡VRAM,以达到提升性能的目的。该方法把图形子系统划分为固定组件和流动组件两类。对于固定组件,采用飞腾1500A访问I/O设备的指令替换内存拷贝指令,使固定组件能够直接访问VRAM,从而将图形数据拷贝到VRAM中,以提高显卡工作效率;对于流动组件,则继续使用主存作为显存。实验结果表明,采用该管理方法后,基于飞腾1500A处理器的计算机图形显示整体性能在某些显卡中大幅提升,其中3D显示性能有数倍的提升,并且不会产生段错误;即使对2D图形大概有10%的性能下降,亦能适于运行大量3D图形应用的场景。In phytium 1500A processor-based computer system,the existing operating system graphics subsystem could produce segment errors when copying data between main memory and graphics card VRAM （ video memory）, which causes that the graphics subsystem can only use main memory as video memory and cannot be used VRAM directly. Because main memory access is so slower than access- ing VRAM directly by graphics card that the problem in some scenes limits the efficiency of the graphics card, thereby limiting the per- formance of the graphics subsystem. Therefore, an optimization method of graphics system memory management with the Phytium 1500A processor has been presented,which permits the system equipped with graphics card VRAM,for the purpose of performance promotion. The graphics subsystem is composed of two types of components, fixed and mobile components. In the former of which the instructions of I/O devices can be used to replace memory copy instructions with Phytium 1500A processor by using VRAM which could copy the pat- tern data to the VRAM for efficiency promotion of the graphics card ; in the latter of which the main memory can be used as video memo- ry. Experimental results show that the Phytium 1500A processor-based computer graphics display performance has been significantly im- proved, wherein the 3D display performance has been promoted several times higher without mistake and that even if there is about 10% performance degradation for 2D graphics,the VRAM is also suitable for a large number of scenes with 3D graphics applications.

关 键 词：图形子系统 显示优化 显存 VRAM 

分 类 号：TP39[自动化与计算机技术—计算机应用技术]