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What is VirtualAlloc usage?

What is VirtualAlloc usage?

The VirtualAlloc function can be used to reserve an Address Windowing Extensions (AWE) region of memory within the virtual address space of a specified process. This region of memory can then be used to map physical pages into and out of virtual memory as required by the application.

Does HeapAlloc call VirtualAlloc?

Allocates whatever size of memory you ask for, not in big chunks than VirtualAlloc . HeapAlloc knows when it needs to call VirtualAlloc and does so for you automatically. Like malloc , but is Windows-only, and provides a couple more options.

How do I check virtual memory utilization in Windows?

To start Performance Monitor, click Start, click Control Panel, click Administrative Tools, and then double-click Performance Monitor. Here is a summary of some important counters and what they tell you: Memory, Committed Bytes: This counter is a measure of the demand for virtual memory.

Does Kmalloc zero memory?

void *kzalloc(size_t size, gfp_t flags); works like kmalloc, but also zero the memory. kmalloc() will return a memory chunk with size of power of 2 that matches or exceeds len and will return NULL upon failure. The maximum size allocatable by kmalloc() is 1024 pages, or 4MB on x86.

What is Kmalloc and Vmalloc?

The kmalloc() function guarantees that the pages are physically contiguous (and virtually contiguous). The vmalloc() function works in a similar fashion to kmalloc() , except it allocates memory that is only virtually contiguous and not necessarily physically contiguous.

What is QueueUserAPC?

The Win32 API provides the QueueUserAPC function, which allows an application to queue an APC object to a thread. The queuing of an APC is a request for the thread to call the APC function. When a user-mode APC is queued, the thread is not directed to call the APC function unless it is in an alertable state.

How do I find current process handle?

how to get current Process HANDLE?

  1. C# Copy Code. The return value is a pseudo handle to the current process.
  2. ASM. Copy Code. DWORD pid = GetCurrentProcessId(); HANDLE hProcess2 = OpenProcess(0, FALSE, pid);
  3. Copy Code. HANDLE hProcess2 = OpenProcess(PROCESS_ALL_ACCESS, FALSE, pid);

How do I use HeapAlloc?

To allocate memory from the process’s default heap, use HeapAlloc with the handle returned by the GetProcessHeap function. To free a block of memory allocated by HeapAlloc, use the HeapFree function. Memory allocated by HeapAlloc is not movable.

How do I check my virtual memory on Windows 7?

2.1. 2 Checking the Currently Configured Virtual Memory on Windows Systems

  1. From the Control panel, select System.
  2. In the System Properties window, select the Advanced tab.
  3. Under Performance, click Performance Options, or Settings.
  4. In the Performance Options window, click the Advanced tab.

What is a good virtual memory size for Windows 7?

Note: Microsoft recommends that virtual memory be set at no less than 1.5 times and no more than 3 times the amount of RAM on the computer. For power PC owners (most UE/UC users), there is likely at least 2 GB of RAM, so the virtual memory can be set up to 6,144 MB (6 GB).

When should I use Kmalloc?

Kmalloc() is use to allocate memory requested from the kernel. The memory allocated is returned by the API and it is physically as well virtually contiguous.