瀏覽單個文章
BanjoWind
Regular Member
 

加入日期: Mar 2015
文章: 66
引用:
作者commando001
剛剛查了一下推土機架構的圖

http://www.anandtech.com/show/2881

裡面的內文

Behind the FP scheduler are two 128-bit wide FMACs. AMD says that each thread dispatched to the core can take one of the 128-bit FMACs or, if one thread is purely integer, the other can use all of the FP execution resources to itself.http://images.anandtech.com/reviews...e/bulldozer.jpg

模組中都在做浮點運算時每個核心都會拿到1個128bit FMAC來做運算

所以推土機系列的浮點數運算器算是能拆的?
...

不能拆,您應該以AMD官方編號47414的Software Optimization Guide為準:

=========================================
"The FPU can receive up to four ops per cycle."
===> 每個時脈內,FPU可以接受最多4個微指令

"These ops can only be from one thread,"
===> 這些(最多4個)微指令,必須是來自同一個執行緒(該時脈內)

"but the thread may change every cycle."
===> 但是每個cycle,可以切換成不同的執行緒(來使用整個FPU)
=========================================

FPU是不能拆的,而是以cycle為單位,讓兩個執行緒輪流使用。
舊 2015-09-19, 05:29 PM #9
回應時引用此文章
BanjoWind離線中