Nokia Energy Profiler 1.2 is a stand-alone test and measurement application for S60 3rd Edition, Feature Pack 1 and later devices. The application enables developers to test and monitor their applications’ energy usage in real time on target devices.
The application is available as a SIS package for S60 3rd Edition and later devices. The Nokia Energy Profiler’s measurement features work only on S60 3rd Edition, Feature Pack 1 and later devices. The application can be used as a profile-file viewer on devices based on S60 3rd Edition.
Installation
You can transfer the installation package (SIS) to a device in one of several ways, such as by use of a USB or Bluetooth connection, by MMC, or by a direct download from the internet. In the example given below, the application is transferred and installed using a USB cable and Nokia PC Suite. If you have an earlier Nokia Energy Profiler version installed, you don’t have to uninstall it before installing the new version.
1. Use a USB cable to connect the device to a PC.
2. Select PC Suite and OK on the device when prompted to select a USB mode (Figure 1).
4. Select Yes in the installation-confirmation message on the PC.
Nokia PC Suite then transfers the SIS package automatically to the device and starts the installation procedure.
5. Select Yes in the installation-confirmation messages on the device (Figure 2).
6. Select Continue on the device’s Details screen (Figure 3).
7. Wait until the progress bar on the device’s screen shows that the application is fully installed.
Figure 1: After making the USB connection, select PC Suite.
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Figure 2: Select Yes to confirm and begin installation. |
Figure 3: View installation details. |
After the application has been installed, the device returns to its preinstallation state. When you see an ’Installation complete’ message on your PC, you can detach the USB cable. You’re now ready to run your first measurements with the Nokia Energy Profiler.
Usage
The Nokia Energy Profiler application is placed in the installed-applications folder of your device. This folder’s name is
Applications or Installations.
1. Start the application by navigating to its icon and pressing the Select key. A banner is displayed once the application starts (Figure 4).
2. Use either Options > Start (Figure 5) or the [2] key to start tracing and recording the device’s power consumption.
Figure 4: Start banner with version information is displayed. |
Figure 5: Start measurements from the Options menu. |
Figure 6: A trace session running in the Nokia Energy Profiler is shown. |
A blinking red dot and a power-consumption graph are drawn on the screen (Figure 6). Press the Up and Down keys to change the vertical scale.
Leave the Nokia Energy Profiler running and perform your testing. Note that pressing the End key
sends the Nokia Energy Profiler to the background. Holding the Applications key 
and choosing Energy Pro. switches the profiler to the foreground.
Once testing is completed, go back to the Nokia Energy Profiler application and select Options > Stop to stop the measurements. Save the results by selecting Options > File > Save.
Now you can simply study the results on the screen or select Options > File > Export to export them in various formats for later analysis (Figure 7 and Figure 8). Exporting as CSV preserves all the measurement data and enables you to process it in Microsoft Excel or other ways. The native JCE files are binary data, and its format description has yet not been released.
Figure 7: Select an export option in the Nokia Energy Profiler. |
Figure 8: Exported CSV text files can be opened in Excel. |
Keyboard controls
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[2] |
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Start and stop measurements |
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[5] (hold) |
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Insert marker |
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[7] (hold) |
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Toggle between portrait and landscape orientations |
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[8] |
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Toggle between instant and average bars |
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[8] (hold) |
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Paint graph area (time-selection mode) |
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[0] |
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Switch between views |
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[0] (hold) |
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Enter/exit dual view |
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[*]/[#] |
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Zoom in/zoom out on the graph’s time axis |
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Up, Down |
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Zoom in/zoom out on the graph’s value axis |
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Left, Right |
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Scroll |
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Joystick centre (hold) |
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Show a screen shot (when available) |
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Camera |
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Take a screen shot (default key) |
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Power |
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Take a screen shot on a touchscreen device |
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End |
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Send the application to the background |
 Figure 9: A part of the measurement can be examined with the time-selection mode. |
Figure 10: A screen shot captured during measurement shows what was displayed on the UI at the red marker. |
Touch
The joystick’s Up, Down, Left, Right, and Select keys are mapped directly to the screen (Figure 11) on phones with a touch UI. Keyboard shortcuts are represented as toolbar icons (Figure 12). Scrolling the results graph can be achieved by holding and dragging the graph. A long-tap access shows screenshot, extended zoom levels (in scale extremes), and continuous scrolling. Time-selection mode is through double-tap and hold, and then painting an area.
Figure 11: Joystick keys are directly mapped to the screen.
Figure 12: Use toolbar icons or Options to access other features.Figure 12 shows toolbar icons in portrait and landscape orientations. The basic toolbar consists of three icons: change view, toggle between instant and average bars, and access more icons. More icons are (row by row from top-left in the portrait screen shot of Figure 12): add grey marker, toggle landscape/portrait, dual-view mode, zoom in time scale, change corner indicator, and zoom out time scale.
Screen icons
The screen shots in Figure 13, Figure 14, and Figure 15 come from a recording on a Nokia N81 device. The data was recorded while the device’s camera application was open and a photograph was taken.
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~3.97V |
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Average voltage during the measurement (Figure 13) |
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3.94V |
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1x |
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Time-axis zoom level |
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8:17 |
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Estimated time, in hours and minutes, that a full battery would last with the measured average power consumption |
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White box/red dot |
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View mode/record mode |
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Vertical grey line |
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Start or end of a measurement region |
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Vertical red line |
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Indication that a screen shot was taken |
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Green line (top of screen) |
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Available storage memory of phone or memory card; full screen width corresponds to 64 MB |
Figure 13: Average power consumption was 0.54W during the measurement. Note that the measurement and average span cover not
only the graph visible on the screen. The red vertical bar shows that a screen shot was taken. |
Figure 14: Instant power consumption was over 1.03W when this screen shot was taken. Peaks in the power graph are generally
not a problem, but it is high baseline consumption that causes high energy consumption. |
Figure 15: Switching to current-consumption view shows 0.26A. From version 1.2 onwards the values are displayed as mA. |
Measurement views
The Nokia Energy Profiler supports the following views:
- Power.
- Current.
- Processor.
- RAM Memory.
- Network Speed.
- WLAN.
- Signal Levels.
- Energy.
- Voltage.
- 3G Timers.
To switch between views, press the [0] key. To toggle between portrait and landscape orientations, hold the [7] key.
Power view
Figure 16: Power view displays watts (W).
Power view (Figure 16) shows power consumption over a measurement period. The basic unit is a watt (W). You can switch between average and instant power.
The average bar displays the mean power value for the active measurement region that is delimited by vertical grey markers. You can add markers, but you cannot delete them afterwards. Time-selection mode enables you to examine a section of the graph. The corner indicator shows either battery time or total energy consumed in the region. Battery time is the estimated time that will elapse before the battery is fully discharged. This estimate is based on the average power measured over the entire region of the graph. Note that normal indicators refer to the entire active region. In time-selection mode, the indicators change according to the painted area.
Current view
Figure 17: Current view shows milliamperes (mA).
Current view (Figure 17) displays current consumption, which is the measured current draw from the battery. As the battery discharges, voltage drops and current increases so that power consumption stays roughly constant. Current consumption for the same use case varies according to battery-charge level. You can select the experimental Tools > Normalize current function to recalculate the current measurements for a standard 3.7V reference voltage. The corner indicator values in Current view are the same as in Power view.
Processor view
Figure 18:Processor view shows processor load as a percentage.
Processor view (Figure 18) shows the CPU load over a measurement period as a percentage of the total available CPU-processing capability. Values are between 0 per cent and 100 per cent, where 0 per cent is no processing and 100 per cent is maximum processing. Note that different mobile devices have different CPUs, such as ARM9 and ARM11. Cache sizes, memory bandwidth and latency, and chipset performance also vary. For details, see Nokia device specifications.
RAM Memory view
Figure 19: RAM Memory view displays memory usage in megabytes.
RAM Memory view (Figure 19) displays the RAM memory usage over the period. The unit is megabytes. The bright-blue line represents the allocated memory, and the light-blue line is the total RAM available to S60 software. The RAM available to software differs from the total amount of physical DRAM in a device, because memory may be reserved for exclusive use. The delta symbol indicates the difference between maximum and minimum memory usage over the region. This difference in the amount of memory used is the overall operating system usage, not just that of your application. The delta symbol value illustrates the memory dynamics of the application during the measurement. The memory may have been allocated not only by your application but also by the operating system components it depends on. For this reason, a difference in initial and final memory-usage values does not necessarily mean a memory leak. It is wise to check applications running in the background if memory consumption slowly rises over days, which eventually causes a memory-full error.
Network view
Figure 20: Network view displays downlink and uplink data-connection speeds in kilobytes per second.
Network view presents the downlink (download) and uplink (upload) speeds through the IP stack. The unit is kilobytes per second. Downlink and uplink speeds are shown simultaneously on the screen in green and orange, respectively. Note that you can combine this view with other views, through the dual-view feature, by holding the [0] key. The average and instant bars are for either downlink or uplink data, depending on the selected input. You can toggle the data input with the [6] key. The same key also toggles the corner indicator that has the total amount of data transferred for the downlink (arrow down) or uplink (arrow up).
WLAN view
Figure 21: WLAN view enables you to study application behaviour in various signal-strength conditions.
WLAN view (Figure 21) shows received-signal strength when the device is connected to a WLAN base station. In the active standby screen, the WLAN icon is visible in the top-right corner. The received-signal strength is measured in decibels referred to 1 milliwatt (dBm), and values typically are in the range of -40 to -90 dBm. Values closer to -40 indicate very good signal conditions.
Signal Levels view
Figure 22: Signal Levels view shows receive and transmit values
dBm).
Signal Levels view shows the cellular signal levels as RX and TX levels. The RX level corresponds to the power of the received cellular signal. The TX level refers to the transmission power from the cellular radio. Both measures are in dBm. TX levels show up only during active transmission periods (voice or data). RX levels are available whenever the device is connected to a cellular network. This means there is no RX level in the Offline phone profile. Average/instant-bar values are for the selected signal shown in the corner indicator. You can toggle the chosen signal with the [6] key. Unlike in all the other views, the zero y-axis is at the bottom of the screen. RX levels are typically between -30 and -120 dBm (a lower value means a poorer signal), whereas TX levels are positive dBm (a higher value means more power). The tool does not yet measure 2G (GSM/EDGE) data TX values.
Energy view
Figure 23: Energy view is shown.
Energy view (Figure 23) shows the cumulative energy consumed over the measurement period. The unit used is milli-Ampere-hour (mAh). Although this is not the unit for energy, it is commonly used to rate the capacity of rechargeable batteries. Energy view is not available during recording because it is computed in real time. The view is Off by default. Select Options > Settings and the Views tab to activate it.
Voltage
Figure 24: Battery voltage can be examined in Voltage view.
Voltage view (Figure 24) shows the battery-voltage levels. As the battery discharges, its voltage level decreases from roughly 4.2V to 3V until the phone switches itself off. Shutdown actually happens before the battery is totally exhausted, and thus the Battery Time estimate and true operating time are slightly different. The view is Off by default. Select Options > Settings and the Views tab to activate it.
3G Timers view
Figure 25: 3G Timers usage with dual-view mode is shown. The power-consumption graph closely follows a 3G network’s state.
3G Timers view (Figure 25) shows the 3G-network-data inactivity timers, also known as T1 and T2. Possible 3G data-channel states are DCH, FACH, PCH_URA/PCH_CELL, IDLE, and Out-of-Zone. These are simply mapped to integers 8, 4, 3, 1, and 0, respectively. Transitions between these states are dictated by an operator’s network configuration. The view is somewhat experimental and generally requires advanced use of dual-view mode, together with either Network view or Power view. The display backlight should be kept on during tests to prevent the mobile device from going to sleep. Timers can be in the 2- to 120-second range. Nokia experiments indicate that the best networks for always-on applications have 2 seconds for both T1 and T2.
Hints and tips
Keep the following information in mind when using the Nokia Energy Profiler:
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 Figure 26: When the charger is connected, the x-axis is bright red. |
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Figure 27: This emergency-save illustration shows both current and voltage in dual-view mode.
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Figure 28: Having the Nokia Energy Profiler in the list of active standby applications makes using it easier. Press the End
key to move the Energy Profiler screen to the background.
The Nokia Energy Profiler External APIs are available on the Nokia Developer website. These APIs enable developers to control data capture and create customized measurement.
Place the Nokia Energy Profiler first in your list of active standby applications. That way, you can quickly switch to it from the active standby screen. (See Figure 28.)
Do at least power-consumption and CPU-load tests during your S60 or Java™ application development. It is a very tedious task to change software architecture and application behaviour once it is ready for end users.
Key terminology
Display states are: Active, Dimmed, Standby, and Off. Active and Standby are the important ones. See Table 1 for definitions. Use exactly these words, because otherwise others will misunderstand explanations of your test cases and measurements.
| Name | ACTIVE | DIMMED | STANDBY | OFF |
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| UI | Normal | Normal | Partial | Off |
| Backlight | On | Off | Off | Off |
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Table 1: Display-state names for use in explaining the status of the UI and backlight are shown.
Figure 29: Backlight is on three times during this measurement.
One measurement run produces a measurement region. This area is delimited with grey marker lines.
A captured screen shot is shown as a red marker on the screen.
The application shows instant/average value, which is indicated with a line called instant/average bar.
Please use the Instructions feature (by selecting Options > Instructions), because it contains very useful information. Also see Options > About for the Nokia Energy Profiler support and feedback e-mail address.
