Arm Community
Site
Search
User
Site
Search
User
Groups
Arm Research
DesignStart
Education Hub
Graphics and Gaming
High Performance Computing
Innovation
Multimedia
Open Source Software and Platforms
Physical
Processors
Security
System
Software Tools
TrustZone for Armv8-M
中文社区
Blog
Announcements
Artificial Intelligence
Automotive
Healthcare
HPC
Infrastructure
Innovation
Internet of Things
Machine Learning
Mobile
Smart Homes
Wearables
Forums
All developer forums
IP Product forums
Tool & Software forums
Pelion IoT Platform
Support
Open a support case
Documentation
Downloads
Training
Arm Approved program
Arm Design Reviews
Community Help
More
Cancel
Developer Community
Tools and Software
Software Tools
Jump...
Cancel
Software Tools
Arm Development Studio forum
Questions about code benchmark difference between A8 and A15
Tools, Software and IDEs blog
Forums
Videos & Files
Help
Jump...
Cancel
New
Replies
4 replies
Subscribers
127 subscribers
Views
2141 views
Users
0 members are here
Related
Questions about code benchmark difference between A8 and A15
Offline
Adam Yao
over 7 years ago
Note: This was originally posted on 1st May 2013 at http://forums.arm.com
[size="3"]Hi all,
I tested some protocol stack code's benchmark in Cortex A8 and A15. The code is same and I enabled L1/L2 cache and branch prediction in both CPUs (I placed all the codes and data in DDR and configurated DDR's MMU attribute to WB&WA for both L1 and L2 cache). Basicly A15's result is bettern than A8, but there is something I can not explain. The resut is as below:
A8 A15
Overall cycles 71821 30057
L1I cache miss 469 431
L1D cache miss 1015 139
L2 cache read miss 78 584
L2 cache write miss 247 26
mis-predicted/no predicted branch 469 217
predicted branch 1015 11385
What confused me are:
[/size](1) Why A15's L1D cache miss number is much lower than A8, both CPU's L1D cache is 32K? So what cause A15's L1D performance improvement?
(2) Why A15's L2 cache read miss number is much higher than A8?
(3) For branch prediction, why the sum of predicted and not predicted branch number is not equal in A8 and A15 and why A15's number is about 10 times A8's number?
Wait for a reasonable explanation.
Thank you.
Parents
Offline
Gilead Kutnick
over 7 years ago
Note: This was originally posted on 6th May 2013 at
http://forums.arm.com
You can find the performance counter numbers in the Cortex-A8 TRM in 3.2.49 (
System Control Coprocessor
>
System control coprocessor registers
> c9, Event Selection Register):
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0344k/index.html
I agree they don't seem to be the same as Cortex-A15's.
Cancel
Up
0
Down
Reply
Cancel
Reply
Offline
Gilead Kutnick
over 7 years ago
Note: This was originally posted on 6th May 2013 at
http://forums.arm.com
You can find the performance counter numbers in the Cortex-A8 TRM in 3.2.49 (
System Control Coprocessor
>
System control coprocessor registers
> c9, Event Selection Register):
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0344k/index.html
I agree they don't seem to be the same as Cortex-A15's.
Cancel
Up
0
Down
Reply
Cancel
Children
No data
More questions in this forum
By title
By date
By reply count
By view count
By most asked
By votes
By quality
Descending
Ascending
All recent questions
Unread questions
Questions you've participated in
Questions you've asked
Unanswered questions
Answered questions
Questions with suggested answers
Questions with no replies
Not Answered
Forum FAQs
0
ARM Community
904
views
0
replies
Started
5 days ago
by
Annie Cracknell
Suggested Answer
How to view SFRs in DS during debugging?
0
308
views
1
reply
Latest
1 day ago
by
Ronan Synnott
Answered
Dual-core debugging in DS
0
3172
views
2
replies
Latest
14 days ago
by
Ivan Savvateev
Answered
Failure to get an evaluation license with error Unable to execute API call /api/v1/connect
0
4107
views
3
replies
Latest
19 days ago
by
Tim Holt
Suggested Answer
DS52020.0 connection to Musca-A/B boards not working
0
Arm Development Studio
Musca-A
5145
views
4
replies
Latest
21 days ago
by
Daniel Oliveira
>
View all questions in Arm Development Studio forum