changing governors for C and P states
How do you change the governor from Ondemand to powersave(say) for P-states ? How do we do the same thing for C-states ? ...
power-management
Changing C-state governor
I learnt that we can change P-state governors with the command echo "ondemand" > /sys/devices/system/cpu/cpu0/cpufreq/current_governor How dooes one change the C state governor ? ...
Server socket programming in Android 1.5, most power efficient way?
Hello people, I am doing a project where I have too develop an application that listens for incoming events by a service. The device that has to listen too events is an Android phone with Android SDK 1.5 on it. Currently the services that call events only implement communication trough UDP or TCP sockets. I can solve my problem by setti...
Accelerometer stops delivering samples when the screen is off on Droid/Nexus One even with a WakeLock
I have some code that extends a service and records onSensorChanged(SensorEvent event) accelerometer sensor readings on Android. I would like to be able to record these sensor readings even when the device is off (I'm careful with battery life and it's made obvious when it's running). While the screen is on the logging works fine on a 2....
Hyper-V, VMware ESX and custom power management
In a research project involving virtualization and power management I am testing various resource allocation scenarios and custom power management algorithms. I am interested in isolating a virtual machine to use only a certain CPU core. I was thinking about using Windows 2008R2 and Hyper-V, but Hyper-V does not allow setting CPU affin...
WM_POWERBROADCAST handler for CMainDlg in ATL app not invoked
I have an ATL app where I want to handle WM_POWERBROADCAST. I have a CMainDlg (CAxDialogImpl) in whose MSG_MAP I defined the handler. BEGIN_MSG_MAP(CMainDlg) ... MESSAGE_HANDLER(WM_POWERBROADCAST, OnPowerChange) ... END_MSG_MAP() However, the handler isn't invoked when I do things that should invoke it, for instance change...
Windows - CPU power management APIs
What APIs are provided by Windows for CPU power management (I'm interested in CPU frequency scaling, setting min and max CPU frequency - similar to what you can do in Control Panel in power plans, but in a programmatic way). I'm also interested in .Net APIs. (It is not something I intend to use in a production environment, but rather as ...
Windows - put HDD stand-by and sleep mode
How can I put a hard disk drive in stand-by or sleep mode in Windows, in a programmatic manner. Does the Windows API or any .Net libraries provide any functions to achieve this? (I am aware that I should probably not interfere with Windows's power management mechanism, but this is not something I intend to use in a production environme...
Adding a new power scheme to Windows Server 2008 R2
I am trying to add a new power scheme to Windows Server 2008 R2. However, the new power scheme has the same settings as the current one. What am I doing something wrong? PGLOBAL_POWER_POLICY globalPolicy = new GLOBAL_POWER_POLICY(); PPOWER_POLICY powerPolicy = new POWER_POLICY(); printf("Idle sensitivity: %d\n", powerPolicy->user.Id...
Stop the screen saver and hibernation temporarily in VB.Net
I have a very long running syncronization task that cannot be interrupted by the screen saver or aggressive power saving modes. I want to make a single api call to stop power save mode and then restore it once the task is done. The following code is peaced together from various other posts but it has no effect on XP's power management s...
GPS Power on HTC Snap/Ozone Dash 3G
I'm using an HTC Snap running WinMo 6.5 Standard and I have a seemingly simple requirement - when the device goes into "BacklightOff" power mode the application needs to continue to collect GPS location data. By default the device shuts down the GPS receiver. I've tried a boatlod of things to achieve this over the last 2 days. I've re...
Getting QT to respond to power-events (sleep/hibernate)
I'm trying to develop software that is intelligent wrt sleep events (cleanly closing network connections, making sure data restart locations are set properly, etc). Are there mechanisms in QT (4.6) currently that facilitate me responding to system power events? ...
When should I care about PowerManagement and wake locks for Android service?
I have an android service that connects to remote server by TCP/IP and waits for notifications from it. Should I care about PowerManagement? Can sleep mode affect me some how? If no, than what are the "use cases" to care about wake locks? ...
How to do power save on a arm based Embedded Linux system?
Hi I plan to develop a nice little application that will run on a arm based embedded linux platform, however since that platform will be battery powered I'm searching for relevant information on how to handle powersave. It is kind of important to get decent battery time. I think the linux kernel implemented some support for this, ...
Calling ReadProcessorPwrScheme() does not return correct values
I would like to ask a question regarding P/Invoke method. I am coding in C# and would like to access the Power Management API (powrprof.dll) method "ReadProcessorPwrScheme". Unfortunately, I am not getting the correct values and I suspect that I may be a problem in marshaling. Any help is much appreciated. Some of the codes that I have: ...
How to enable suspend mode on a Windows Server 2008 R2 box?
I want to use Wake-On-LAN for my two office machines, both of which run Windows 2008 Server R2 (for Hyper-V), but it seems the Server SKU doesn't offer a suspend option anyway. I'm sure it's just a registry key or something. How can I enable my servers to sleep? ...
Finding the WiFi adapter handle for power management
I'm trying to locate the name of the 802.11 adapter to pass to SetDevicePower() and GetDevicePower(). I was going to use FindFirstDevice() with the PMCLASS_NDIS_MINIPORT guid to do this: DEVMGR_DEVICE_INFORMATION di = { 0 }; di.dwSize = sizeof( DEVMGR_DEVICE_INFORMATION ); GUID IID_NdisMiniport = { 0x98C5250D, 0xC29A, 0x4985, { 0xae, 0...
Wakelock is not turning on the screen? Help?
Hey all, I have a signal that puts my app to sleep for a given number of minutes (using AlarmManager) and then wakes it back up. Everything is working except the screen doesn't ever come on. I'm using a wakelock like so from a BroadcastReceiver class: KeyguardManager key = (KeyguardManager) context.getSystemService(Context.KEYGU...
Determine time since last user activity in Android
How do you discover when, in the future, the device is expected to sleep? Or, at least, when the last user activity was? ...
How to keep android device from sleeping while plugged in
I'd like to keep the screen on whenever one of my Activities are running and the phone is plugged in to a power source. I know that Wakelocks are tricky, so I'm looking for an example or some documentation on how to accomplish this specific goal. ...