EV7 vs EV68?

[watermelonyu]

GS1280 是用 EV7? EV7 & EV68 的 CPU performance 哪個比較好?

[watermelonyu]

Hello Eric:



跟據HP網站資料如下:

http://h50007.www5.hp.com/enterprise/product/server/gs1280/default.asp

AlphaServer GS1280 作為其終極運算平台，此套系統現已推出16顆EV7 Alpha處理器版本.

主要特色



‧2至16顆1.15 GHz Alpha 處理器。

‧4 GB / ECC 記憶體；2003年中推出8 GB / 處理器版本；2004年將推出16 GB / 處理器版本

‧51.2 GB/s I/O 頻寬(最大值)

‧每顆CPU內建1.75 MB ECC 第二階快取記憶體。

‧10 至80/160 PCI/PCI-X 插槽、1 至16 組AGP 插槽。

‧支援4或8組系統分區。

‧支援Tru64 UNIX與OpenVMS。



And when you want to know each model of

AlphaServer, except CPU model, you must pay

attention to CPU clock rate, too.



Meanwhile, if you want to evaluate system

performance, memory bandwidth, I/O bandwidth,

I/O throughput, CPU numbers, memory size and

so on must be taken into consideration.



Please read the spec on HP web site for

more information that you can refer to.



Best Regards

Danny

[watermelonyu]

Hi Danny,



網路上有一篇文章

http://h18002.www1.hp.com/alphaserver/download/Compaq_EV7_Wp.pdf





"Next generation AlphaServer systems are based on the same EV68 core used in current

AlphaServer systems. Indeed, this core runs slower in the new AlphaServer ES47 and ES80

systems (at 1.0 GHz) than in the current AlphaServer ES45 systems (1.25 GHz). The seven-way

set associative cache behaves like a 12-16 MB L2 cache, but the current AlphaServer ES45

has a 16 MB L2 cache. Similarly, the new AlphaServer systems are running slightly slower

(at 1.15 GHz) than the current AlphaServer GS320 system (at 1.224 GHz) which has a

16 MB L2 cache.

As a result, applications that only stress the processor and cache and are running on the new

AlphaServer systems demonstrate little performance improvement over the same applications

running on current systems. Applications that stress the memory subsystem of a single processor

demonstrate some performance improvements over current systems. And applications that stress

the memory subsystems of many processors in SMP environments demonstrate substantial

improvements over current systems."



So the Ev7 specifically allows us to scale out to large SMP configs with high bandwith needs for lots of IO and memory. For raw CPU power the ES45 may beat it for certein applications. 'it depends'.



========

純就 CPU 來分析, EV7 的 performance 是否比 EV68 好呢? Pls kindly share your opinion.

[watermelonyu]

Hello Eric:



就如同您提供的資料來看: EV7chip是EV68的加強版-(例如:L2 Data, L2 Tag, Mem Controller...), 所以理論上EV7應優於EV68,但是CPU clock也應列入考量. (Ref P5,

Fig-1 and P8 Fig-3)



這裡也有一份doc,提供參考:

http://h18002.www1.hp.com/alphaserver/download/next_gen_wp_0203.pdf

page 9有benchmark data,注意GS1280(1.15GHz)優於ES45(1.25GHz)這些都需要考量CPU clock rate, CPU

numbers, Memory Bandwitdh, Memory Interleaving,

even I/O bandwidth, 才能評斷哪一型機器最合乎您的需

求, CPU最快不一定最好, 可擴充性也很重要!



Best Regards

Danny