3.2 Capture & Analysis Options dialog box settings
The Capture & Analysis Options dialog box enables you to change the capture session settings, including the IP address of the target, duration, sample rate, and buffer size.
Figure 3-2 Capture & Analysis Options dialog box
The Connection section contains the following settings:
- The IP address of the target. You can alternatively enter
the network name of your target. The value given in this field overwrites
the value in the Address field of
the Streamline Data view, if one has
been given. The reverse is also true. If you enter a new address in the
Address field of the Streamline Data
view, it replaces the value entered here.
By default, Streamline uses port 8080 to connect to a
target. To use a different port, specify one here by
entering a colon and a port number after the IP address. For
Your_IP_address:1010 to use port
1010 to connect to the target.
If you use the port forwarding of Android
ADB with USB, enter localhost in the Address field.
- Browse for a
- Use the Browse for
a target button on the right side of the
Address field to
open the Connection
Browser. Streamline searches your network and produces a list
of possible targets. Selecting one populates the Address field.
- ADB Path
- The location of the ADB executable. You need to specify
this in order for the Connection
Browser and the Setup
Target... dialogs to list targets connected using ADB.
The Capture section contains
the following options:
- Sample Rate
- The target generates periodic measurement interrupts
according to the following settings: Normal=1kHz, Low=100Hz, and None. The
Normal setting works well in most
cases. Low is recommended if you have
a slow target, or if the target is heavily loaded, because it means less
intrusion by Streamline. The Low setting requires a longer capture to collect
representative data. Set Sample Rate to None to ensure that Streamline
has the lowest level of intrusion on your code, but this also means that
resulting reports show only zeroes in any report columns that rely on
- Buffer Mode
The default setting is Streaming, which enables unbounded streaming of target
data directly to your host using a 1MB buffer. You can also use one of
the following store-and-forward buffers:
If you select one of these sizes, the capture ends when
the buffer is full. This prevents the intrusion caused by streaming data
from the target to the host.
NoteYou must set the Buffer Mode to Streaming to enable Live view. If you select one of the
buffer sizes, Live view does not
display real-time data during the capture session.
- Call stack
- Select this checkbox to ensure that Streamline
records call stacks. This greatly improves the visibility of the behavior of
the target, but increases the amount of raw data Streamline
sends from the target to the host. Make sure you compile your EABI images
and libraries with frame pointers enabled using the
-fno-omit-frame-pointer compilation option. If GCC is compiled
--with-mode=thumb option, you
must also use the
Streamline supports call stack unwinding for ARM
binaries created using GCC or ARM Compiler 6
(armclang), provided you compile them
with frame pointers enabled. Streamline does not support call stack unwinding
for code generated by ARM Compiler 5 and earlier (armcc).
User space gator does not support call stack unwinding.
- Discard Data
If this option is enabled, Streamline discards all data when you terminate the capture. Use this option if
you only want to see the data that streams during a capture session and
do not want to generate a capture.
If you select this option, the Stop capture and
analyze button in the Live view is disabled.
- The length of the capture session, in minutes and seconds.
For example, enter 1:05 for 1 minute and 5 seconds. If you do not provide a
value here, the capture session continues until you stop it manually, or the
buffer is full.
To use the following Command settings, you must use the
-a option when starting
- The absolute path of the directory on the target in which
to run the command specified in the Command field.
- User Name
- The user account to run the command as.
- A command to run on the target. The command is run a few seconds after the
capture begins. The capture is not automatically terminated when the command
The following settings define your energy capture device:
- Energy Capture
- This menu has three options. Select No Energy Data Collection to turn energy
capture off. When you enable this option, all other energy capture options
are disabled. Select ARM Energy Probe
or National Instruments DAQ to match
your energy capture hardware.
- Use this field to give Streamline
the name of your target energy capture device. Streamline
attempts to auto-detect your device if this field is left blank.
NoteWhen using ARM Energy Probe on Linux, enter /dev/ttyACM0 in the Device field, if required. When using
NI-DAQ, the device name is usually Dev1.
- The port Streamline
uses to communicate with your chosen energy capture device. The default port
- Tool Path
- Use this field to define the path to the caiman executable, which is required to use
either the ARM® Energy Probe or a NI-DAQ device to gather power
output statistics. The button to the right of this field enables you to
search your file system.
In addition to the settings that define your capture device, the
Energy Probe section has configuration options that apply to each channel:
- When enabled, Streamline
collects power data on this channel.
- When enabled, Streamline
collects voltage data on this channel.
- When enabled, Streamline
collects current information for this channel.
- Use this field to define the value, in milliohms, of the
shunt resistor that connects to each of the available channels. The default
setting is 20 milliohms.
The Analysis section contains the following controls:
- Process Debug Information (when
- If you enable this option, Streamline
processes DWARF debug information and line numbers. This provides a higher
level of detail in your captures, but results in higher memory usage. This
option does not affect the data collected during the capture session. It
only affects the report data automatically generated after the termination
of the capture session. This option can be changed when you re-analyze the
You must have built the image using the
-g compiler option in
order to enable this feature.
If you disable this feature, the source
section of the Code
view does not display the source code or source code
statistics. The disassembly is still available with this
option disabled, but the source section shows only a No source available
- High Resolution
If you select this checkbox, Streamline processes more data, enabling you to zoom in further in the Timeline view. By default, the highest
resolution in the Timeline view is
milliseconds, but with this option enabled, you can zoom in to
microsecond bin sizes.
This option does not affect the data collected during
the capture session. It only affects the report data automatically
generated after the termination of the capture session. This option can
be changed when you re-analyze the stored capture data.
Use this area to explore your file system and define all of the
images and libraries that you want to profile.
The images defined here do not affect the data collected during the
capture session. They only affect the report data automatically generated after the
termination of the capture session. These images can be changed when you re-analyze
the stored capture.
When compiling images on your host, make sure you set
-g compilation option to enable
Disabling inlining with the
-fno-inline compiler setting substantially improves the
call path quality.
As an alternative to manually selecting images and libraries on the host
in the Program Images section,
Streamline supports automatic image transfer. To use this feature,
specify a regex in the Live
view. Streamline automatically transfers images whose name matches the
regex, and optionally any libraries used by them, from the target to the
If you manually select an image in the Program Images section and also specify
a regex that matches an image with the same name, the image specified
manually is used.
The following buttons are included in the Program
Add ELF Image...
Opens a file system dialog box that you can use to choose
images to add. Select the image, executable, or Android Package File (APK)
and click Open to add the file to
Toggle Symbol Loading
Activates or deactivates symbol loading for the selected image,
executable, or APK. An eye appears next to any entry in the list with symbol
loading turned on.
Figure 3-3 Symbols loaded icon
Using this option instead of removing an entry from the list makes it
easy to toggle an entry on and off over multiple runs, as it does not remove
it from the Program Images list.
Removes the selected entries.
- Use the resulting file system dialog box to find an
existing session.xml file and import
its settings to the Capture & Analysis
Options dialog box.
- Saves the current settings as an xml file.
- Saves the settings and exits.
- Discards all changes and exits.