ICACHE.MISSES Parameter on Xeon-E5

[Ayam]

Hello,

I am using intel xeon E5-24xx machine. When I try to read the parameter ICACHE.MISSES, most of the applications are reporting its values as 0. If I am not mistaken it is the Instruction cache misses of L1. 

Please give me any idea how to check why this parameter is giving 0 value.

Regards

[Peter_W_Intel · Accepted solution]

You may change default SAV to small value to capture more samples, I give you example:

# amplxe-cl -collect-with runsa -knob event-config=ICACHE.MISSES:sa=5000 -knob enable-stack-collection=true -- ./matrix2amplxe: Collection started. To stop the collection, either press CTRL-C or enter from another console window: amplxe-cl -r /home/peter/problem_report/r016runsa -command stop.
Elapsed time = 0.590000 seconds
amplxe: Collection stopped.
amplxe: Using result path `/home/peter/problem_report/r016runsa'
amplxe: Executing actions 16 % Resolving information for `ld-2.12.so'          
amplxe: Warning: Cannot locate debugging symbols for file `/lib64/ld-2.12.so'.
amplxe: Executing actions 16 % Resolving information for `libc-2.12.so'        
amplxe: Warning: Cannot locate file `vtsspp.ko'.
amplxe: Executing actions 16 % Resolving information for `vtsspp'              
amplxe: Warning: Cannot locate debugging symbols for file `/lib64/libc-2.12.so'.
amplxe: Executing actions 17 % Resolving information for `libpthread-2.12.so'  
amplxe: Warning: Cannot locate debugging symbols for file `/lib64/libpthread-2.12.so'.
amplxe: Executing actions 50 % Generating a report                             

Collection and Platform Info
----------------------------
Parameter                 r016runsa                                                                  
------------------------  ---------------------------------------------------------------------------
Application Command Line  ./matrix2                                                                  
Operating System          2.6.32-71.el6.x86_64 Red Hat Enterprise Linux Server release 6.0 (Santiago)
Computer Name             snb01.sh.intel.com                                                         
Result Size               1726725                                                                    
Collection start time     23:05:56 08/04/2014 UTC                                                    
Collection stop time      23:05:56 08/04/2014 UTC                                                    

CPU
---
Parameter          r016runsa                              
-----------------  ---------------------------------------
Name               Intel(R) Core(TM) Processor 2xxx Series
Frequency          3392078523                             
Logical CPU Count  4                                      

Summary
-------
Elapsed Time:  0.761
CPU Time:      0.584

Event summary
-------------
Hardware Event Type               Hardware Event Count:Self  Hardware Event Sample Count:Self  Events Per Sample
--------------------------------  -------------------------  --------------------------------  -----------------
CPU_CLK_UNHALTED.REF_TSC                         1982463296                              1011  2000003          
ICACHE.MISSES                                        105801                                21  5000             
Synchronization Context Switches                          0                                 0  0                
Preemption Context Switches                              63                                63  0                
Wait Time                                                 0                                 0  0                
Inactive Time                                        867741                                63  0                
Energy Core                                        12049264                               593  0                
Energy GFX                                           162176                               593  0                
Energy Pack                                        14334528                               593  0                
amplxe: Executing actions 100 % done  

[Ayam]

@Peter Wang thanks you so much. It has solved the issue.

However, can you please explain what is -knob enable-stack-collection=true. It is giving the readings of Energy Core and Energy DRAM. Can I say that these parameters are telling the energy reading for core and dram of a particular application.

[Peter_W_Intel]

I'm glad that the problem has been solved.

> It is giving the readings of Energy Core and Energy DRAM. Can I say that these parameters are telling the energy reading for core and dram of a particular application.

Energy counters are supported by some processors, they tell us about time wasted on core or on dram, you can see some inactive time in my result.