Introduction
Intel® System Studio is Intel’s suite of software tools for embedded processors and contains features that allow you to profile your entire system and not just the individual cores. This article will describe a new method of profiling your system on an embedded target.
Background
There are several techniques you can use to profile your system. This article uses the command line version of VTune™ Amplifier for Systems known as amplxe-cl. The amplxe-cl program now contains the option to specify a remote target. To profile your system you need to specify the proper analysis type, this article will analyze the memory bandwidh on a system.
We will be using the Intel processor, code named Sandy Bridge. The command for profiling your system is as follows:
amplxe-cl –target ssh:root@ip_addr –collect snb-bandwith -d 5 --search-dir bin:p=<local directory containing modules>
- -target ssh:root@ip_addr
- This specifies that this will be a remote collection over ssh to the system running at internet address ip_addr.
- -collect snb-bandwidth
- This specifies that we will be collecting memory bandwidth on an Intel target, code named Sandy Bridge.
- -d 5
- This specified the collection will run for 5 seconds.
- --search-dir bin:p=<local directory containing modules>
- For system-wide collection, a lot of modules running in the system during the colelction are copied from the target to the host, which may take a while. However, this only happens once since amplxe-cl caches the target system modules on the host for faster access during the next collection. If you do not want the command to take the modules from the device you can specify a local directory on the host to be searched first as above. See the VTune Amplifier for Systems help for more information.
VTune Amplifier 2014 for Systems will create a result directory containing the data you collected. To view the data you would use the command:
amplxe-gui r001bw
(where r001bw is the actual directory containing your results)
Using the Bandwidth View inside of VTune Amplifier for Systems you can see the Read and Write bandwidth expressed in Gbytes per second.
You can also view the PMU (core) and Uncore based events by using the Hardware Events Count view but you will need to view the PMU counters separately from the Uncore counters:
PMU View:
Uncore View:
Summary
VTune Amplifier for Systems contains some powerful new features for profiling your system. Using these remote capabilties, together with the predefined analysis types you can easily collect and view your profiling data and solve the most difficult performance bottlenecks.