How to calculate global memory band width,such as mali-T864 and mali-G52 Mp4?
1、In my past opinion mali-T864 ddr bus width is 64,all core shareing this bus width,ddr frequency is 800MHz, dual channel,so its memory band width is 0.8GHz*64bit/8*2=12.8G/s.It is independent of the core number.But when I read the blog"The Mali GPU: An Abstract Machine, Part 3 - The Midgard Shader Core",it said "The GPU will typically have 32-bits of DDR access (read and write) per core per clock [configurable]",I am very confused,according to this blog,band width is related to the number of cores,each core can read and write per clock.
2、How to calculate mali-G52 mp4 memory band width?
There are two separate things here:* The GPU ability to request data.* The DDR ability to process requests.The Mali-G52 MP4 GPU itself will usually have two 128-bit ports on to the internal bus (one for reads, and one for writes). These run at GPU frequency. With a sufficiently high GPU frequency it will be possible for the GPU to read or write data faster than the DDR can process those requests; in these cases the GPU memory interface will start to stall and wait for the DDR to catch up.You can measure the amount of bandwidth actually used by the GPU for a specific bit of content by using tools such as Arm Streamline, which can be downloaded as part of Arm Mobile Studio here (for Android devices):* https://developer.arm.com/tools-and-software/graphics-and-gaming/arm-mobile-studioHTH, Pete
Thanks for your reply! I will have a try.