i have an App running in windows，and i create an shared_memory (with boost/interprocess) to act as a cache to supply some infos to the app. when i use the shared_memory, i had to insure the shard_memory is alive， indetail that i have to ensure i can get right date from shard_data in below.
shmObjWin = new windows_shared_memory(create_only, trueFileName, read_write, max_memory);
shmRegion = new mapped_region(*(context->shmObjWin), read_write);
shared_data = new(context->shmRegion->get_address()) shared_data_t;
My question is "how to ensure windows shared memory is alive?"
Thanks a lot.
Related
I am simulating a network with 2 wireless hosts and 1 Access point. During runtime a node sets the Access Point's transmit power to zero (to turn it off) by accessing the module and using setDoubleValue(0). But the new values never takes effect. AP's msgs continue to reach the nodes. What am I doing wrong here? I want to turn access point off while the simulation is running. Please help.
cSimulation *currentSimulation = getSimulation();
cModule *tx = nullptr;
tx=currentSimulation->getModuleByPath("agranet.ap.wlan[0].radio.transmitter");
tx->par("power").setDoubleValue(0);
//cPar& po = tx->par("power");
//po.setDoubleValue(0);
I want to turn the access point off while simulation is running.
You cannot change the power parameter after initialization because it is a non-volatile parameter, so its value is read at initialization and cached afterwards. You can manipulate only volatile NED parameters where the C++ code is already prepared for this.
On the other hand, what you are trying to achieve is to disable a node at a certain time, which is what ScenaioManager is for:
https://inet.omnetpp.org/docs/users-guide/ch-scenario-scripting.html
Every time I upload a dicom file, the memory grow up. How can I clean the memory of the old ones
You can see various examples of how to free the memory on the examples code, example on the loader:
let loader = new LoadersVolume();
loader.free(); // Free memory
loader = null;
Another one:
let stackHelper = new HelpersStack();
stackHelper.dispose(); // Free memory
stackHelper = null;
I suggest to read the following document to know how garbage collection works on most browsers.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Memory_Management
The garbage collector deletes from the memory everything that is not referenced somewhere.
Having a high use of memory even if you don't you the object anymore means there still a reference to it somewhere. Look for a variable that can still access to your old data, including the 3D scene, the AMI stackHelper, the AMI loader...
I have a driver that runs in the kernel of a Windows Embedded Compact 2013. The driver is loaded with the "Drivers\BuiltIn" registry key. It accesses a set of HW-registers that are mapped with MmMapIoSpace.
The access to the hardware has some problems. That's why I would like to develop the hardware access in a user mode program and debug the problems. I created a program with VS2013 for that purpose. That's the way we used to go with Windows CE 5.0.
The driver maps the physical address with MmMapIoSpace to the process address space. My program should do the same or something similar. Unfortunately this doesn't work in my program. MmMapIoSpace returns NULL, LastError=87 (invalid parameters). Even CreateStaticMapping returns NULL.
How can I access memory mapped register in WEC2013 without building a new platform for each iteration?
MmMapIoSpace doesn't work in applications anymore since WinCE6.
You maybe could create a driver which maps your hw-register to your user process. Your user process would then obtain this pointer by an ioctl call to this driver.
We mapped some external memory to an application with this method.
VirtualAllocCopyEx() can create a mapping to a specified process.
Hope, this helps. Greetings.
Corresponding to timmfs answer I implemented this code in the driver's XXX_IOControl function:
PHYSICAL_ADDRESS PhysAddress = { 0 };
PhysAddress.LowPart = phys_address;
PVOID pRegister = MmMapIoSpace(PhysAddress, phys_size, FALSE);
HANDLE hCallerProcess = (HANDLE)GetCallerVMProcessId();
HANDLE hCurrentProcess = (HANDLE)GetCurrentProcessId();
PVOID UserSpaceAddress = VirtualAllocCopyEx(hCurrentProcess, hCallerProcess, pRegister, shys_size, PAGE_NOCACHE);
This excerpt shows some solutions for pitfalls I met. So I show how I get all the parameters.
Dear programmers, i wrote a program wich target a Windows Mobile platform (NetCF 3.5).
My programm has a method of answers check and this method show dynamically created pictureboxes, textboxes and images in new form. Here is a method logic:
private void ShowAnswer()
{
PictureBox = new PictureBox();
PictureBox.BackColor = Color.Red;
PictureBox.Location = new Point(x,y);
PictureBox.Name = "Name";
PictureBox.Size = Size(w,h);
PictureBox.Image = new Bitmap(\\Image01.jpg);
}
My problem is in memory leaks or something. If the user work with a programm aproximately 30 minutes and run the ShowAnswer() method several times, Out of memry exception appears. I know that the reason may be in memory allocation of bitmaps, but i even handle the ShowAnswers form closing event and manually trying to release all controls resources and force a garbage collector:
foreach(Control cntrl in this.Controls)
{
cntrl.Dispose();
GC.Collect();
}
It seems like everything collects and disposes well, every time i check the taskmanager on my windows mobile device during the programm tests and see that memory were released and child form was closed properly, but in every ShowAnswer() method call and close i see a different memory amount in device taskmanager (somtimes it usues 7.5 Mb, sometimes 11.5, sometimes 9.5) any time its different, but it seems like sometimes when the method start to run as usual memory is not allocated and Out of memory exception appears.. Please advice me how to solve my problem.. Maybe i should use another Dispose methods, or i should set bitmap another way.. thank you in advance!!!
Depending on how you're handling the form generation, you might need to dispose of the old Image before loading a new one.
private void ShowAnswer()
{
PictureBox = new PictureBox();
PictureBox.BackColor = Color.Red;
PictureBox.Location = new Point(x,y);
PictureBox.Name = "Name";
PictureBox.Size = Size(w,h);
if(PictureBox.Image != null) //depending on how you construct the form
PictureBox.Image.Dispose();
PictureBox.Image = new Bitmap(\\Image01.jpg);
}
However, you should also check before you load the image that it's not so obscenely large that it munches up all of your device's memory.
Edit: I don't just mean the size of the compressed image in memory - I also mean the physical size of the image (height & width). The Bitmap will create an uncompressed image that will take up much, much more memory than is resident on storage memory (height*width*4). For a more in-depth explanation, check out the following SO question:
OutOfMemoryException loading big image to Bitmap object with the Compact Framework
I'm hosting IronPython in a c#-based WebService to be able to provide custom extension scripts. However, I'm finding that memory usage sharply increases when I do simple load testing by executing the webservice repeatedly in a loop.
IronPython-1.1 implemented IDisposable on its objects so that you can dispose of them when they are done. The new IronPython-2 engine based on the DLR has no such concept.
From what I understood, everytime you execute a script in the ScriptEngine a new assembly is injected in the appdomain and can't be unloaded.
Is there any way around this?
You could try creating a new AppDomain every time you run one of your IronPython scripts. Although assebmlies cannot be unloaded from memory you can unload an AppDomain and this will allow you to get the injected assembly out of memory.
You need to disable the optimized code generation:
var runtime = Python.CreateRuntime();
var engine = runtime.GetEngine("py");
PythonCompilerOptions pco = (PythonCompilerOptions)engine.GetCompilerOptions();
pco.Module &= ~ModuleOptions.Optimized;
// this shouldn't leak now
while(true) {
var code = engine.CreateScriptSourceFromString("1.0+2.0").Compile(pco);
code.Execute();
}
Turns out, after aspnet_wp goes to about 500mb, the garbage collector kicks in and cleans out the mess. The memory usage then drops to about 20mb and steadily starts increasing again during load testing.
So there's no memory 'leak' as such.