Intel® VTune™ Amplifier
Similar to the Summary window, available in GUI, the Summary report provides overall performance data of your target. The Summary report is displayed by default after running the collect or collect-with actions.
The summary report displays automatically when data collection completes. To disable this report, use the no-summary option in your command when performing a collect or collect-with action.
You can also generate the Summary report from a preexisting result. Use the report action with the summary report type.
Example 1: Advanced Hotspots Summary
Display the Summary report for the Advanced Hotspots analysis result r010ah. For hardware event-based sampling analysis results, the summary report includes Results and Platform information, summary per the basic metrics, Elapsed time and CPU Usage, and an event summary.
$ amplxe-cl -R summary -r r001ah
Result Info ----------- Parameter r010ah ------------------------ --------------------------------------------------------------------- Application Command Line /home/samples/find_hotspots CPU Name Intel® Xeon® E5 processor Computer Name My Computer Environment Variables Frequency 2700000000 Logical CPU Count 32 MPI Process Rank Operating System Ubuntu 11.04 Result Size 7879077 User Name My Name Summary ------- Elapsed Time: 1.908 CPU Usage: 0.719 Event summary ------------- Hardware Event Type Hardware Event Count:Self Hardware Event Sample Count:Self Events Per Sample ------------------------ ------------------------- -------------------------------- ----------------- CPU_CLK_UNHALTED.THREAD 4258000000 2129 2000000 CPU_CLK_UNHALTED.REF_TSC 3712000000 1856 2000000 INST_RETIRED.ANY 6638000000 3319 2000000
Use the Elapsed Time metric as your performance baseline to estimate your optimizations. The CPU Usage metric is the total CPU time divided by the Elapsed time, which demonstrates an average value of CPU utilization. For example, 'CPU Usage: 5.907' means near 6 cores was running - average, for your program overall. Probably you have 8 cores CPU, so there are potential to parallelize code
Example 2: Concurrency Summary
Generate a summary report for a concurrency analysis result r002cc. The summary portion of the report shows that elapsed time for the target is 4.385s and the average concurrency is 1.015, which means that a single thread was running during most of the elapsed time.
$ amplxe-cl -R summary -r r002cc
Summary ------- Average Concurrency: 1.015 Elapsed time: 4.385
Example 3: Locks and Waits Summary
Generate a summary report for the Locks and Waits analysis result r003lw. The summary portion of the report shows that the multithreaded target spent almost 11 seconds waiting, with an average concurrency of only 1.016. To identify the cause of the wait, view the result in the GUI performance pane, or generate a performance report.
$ amplxe-cl -R summary -r r003lw
Summary ------- Average Concurrency: 1.016 Elapsed time: 4.448 Wait time: 10.96
Example 4: Comparison Summary
Comparing two results is a quick way to check for regressions. In this example, a summary report is generated from two consecutive advanced-hotspot results.
$ amplxe-cl -R summary -r r010ah -r r009ah
Result Info
-----------
Parameter r010lh r009lh
------------------------ --------------------------------------------------------------------- --------------------------------------------------------------------
Application Command Line /home/samples/find_hotspots /home/samples/find_hotspots
CPU Name Intel® Xeon® E5 processor Intel® Xeon® E5 processor
Computer Name My Computer My Computer
Environment Variables
Frequency 2700000000 2700000000
Logical CPU Count 32 32
MPI Process Rank
Operating System Ubuntu 11.04 Ubuntu 11.04
Result Size 7879077 8983332
User Name
Summary
-------
Difference r010ah r009ah
------------- ---------- ------ ------
Elapsed Time: -0.806 1.908 2.714
CPU Usage: -0.083 0.719 0.802
Event summary
-------------
Hardware Event Type Difference:Hardware Event Count:Self Result 1:Hardware Event Count:Self Result 2:Hardware Event Count:Self Difference:Hardware Event Sample Count:Self Result 1:Hardware Event Sample Count:Self Result 2:Hardware Event Sample Count:Self Events Per Sample
------------------------ ------------------------------------ ---------------------------------- ---------------------------------- ------------------------------------------- ----------------------------------------- ----------------------------------------- -----------------
CPU_CLK_UNHALTED.REF_TSC -2138000000 3712000000 5850000000 -1069 1856 2925 2000000
CPU_CLK_UNHALTED.THREAD -2732000000 4258000000 6990000000 -1366 2129 3495 2000000
INST_RETIRED.ANY -3884000000 6638000000 10522000000 -1942 3319 5261 2000000Example 5: General Exploration Metrics in Summary
The General Exploration analysis metrics provide a high-level overview of hardware performance problems. The General Exploration Metrics section appears in a Summary report for hardware event-based sampling analysis results. The set of metrics displayed in the summary depends on the profiled CPU type and list of events.
Information is displayed by execution categories to make it easy to identify which part of the pipeline to focus on. In this example, the CPI Rate is well over 1, indicating there is a problem. In the Back-end Issues category, LLC Miss (Last-Level Cache Miss) indicates CPU cycles are being spent waiting for LLC load misses to be serviced. View the Hotspots
$ amplxe-cl -R summary -r r001ge
General Exploration Metrics --------------------------- Parameter r001ge ----------------------------------- ----------- Hardware Event Count CPU_CLK_UNHALTED.CORE 16219170376 INST_RETIRED.ANY 710657200 CPI Rate 22.823 Retiring uOps 0.024 MS Assists 0.006 FP Assists 0.0 SIMD Assists 0.0 Wasted Work 0.0 Branch Mispredict 0.030 SMC Machine Clear 0.0 Back-end Issues 0.0 Memory Latency 0.0 LLC Miss 0.124 LLC Hit 0.0 DTLB Overhead 0.0 Contested Accesses 0.0 Page Walk 0.022 Bus Lock 0.0 Memory Reissues 0.0 Split Loads 0.0 Split Stores 0.0 Loads Blocked by Store Forwarding 0.0 DIV Active 0.0 Front-end Issues 0.0 ICache Misses 0.0 ITLB Overhead 0.007