How to allocate memory, what is the use of allocating a piece of memory?

If you have an integrated graphics card, you can have a certain "allocation" right in the BIOS, set a value, and if the memory is large enough, then set it to the highest value. Once in the system, the memory is allocated by the operating system itself, and you don't have the right to allocate it.

Good boys. Sweat. How do you allocate hard drives?

I won't divide the memory, and I don't think anyone will.

Modify it, do you really mean virtual memory?

.Sweat. I'm a rookie. Brother professional upstairs.

Categories: Computer Networking >> Programming >> Other Programming Languages.

Analysis: There are many uses for allocating a piece of memory: a stool.

1. If you want the system to run slower or even crash due to insufficient memory, you can repeatedly allocate memory without releasing it.

2. If you need to put some data in the memory, then you must first allocate some space to it to store, and these spaces are the memory you allocate.

3. The program is running in memory when it is running, so there needs to be a place to store the runtime program and data, which is a piece of memory allocated by the system or you.

Not all programs require you to allocate your own memory, and many programming languages have their own internal mechanisms that allocate memory without requiring you to allocate it.

Of course, there are many other uses, but the most basic use is to put some things, of course, these are just data, not watermelons, apples and other things.

Implementation of malloc: In order to allocate memory each time without making a system call (which is time-consuming), the runtime will allocate a large block of memory at once through a system call, and then retail it to the program.

Two system calls that can be used to allocate heap memory:

The area between the data segment and the shared library can be used to allocate heap space. After linux, the loading address of the shared library is placed at the 0xbf000000, which can occupy about about the space, but it is still limited by the memory size + virtual memory space size.

Heap Allocation Algorithm:

The free area is linked together by a linked list, which is allocated by first finding a free block that can accommodate the requested size, and then dividing the block into two parts, one for the area requested by the pre-boring program, and one for the remaining space, and then putting the remaining space back into the linked list. If the remaining space is 0, it is removed from the linked list.

The memory block allocated to the program usually increases by 4 bytes of storage, and the size of the memory block is missing, making it easy to release.

When the user applies for memory, an integer number of blocks are allocated to the user, one block of the allocated area is the head, and the rest is called the body. The state of a block is head body free, which can be represented by two states.

The corresponding bitmap is:

The disadvantage is that the allocation must be an integer multiple of the block size, which is prone to waste.

The heap allocation algorithm tends to be composite, with object pooling for bytes less than 64 bytes, optimal adaptation algorithm for bytes larger than 512 bytes, and optimal compromise strategy for bytes 64 to 512.

1. Open the desktop of the computer, right-click "This Computer", and then select "Properties".

2. Then click "Advanced System Settings".

3. Click "Settings".

4. Click "Advanced" and then "Change".

5. Select "Custom size", enter the minimum and maximum values of virtual memory as needed, and click OK.

Here's how to allocate the memory of drive C to other disks:Tools Ingredients: Thinkbook16P, Windows11.

2. Click Compress Volume. Select Drive C in Disk Management, right-click on the ruler delabel, and click Compress Volume.

3. Set the space ascension point compression. On the Compress page, set the compression space, and then click Compress.

4. Click Extend Volume. Select the D drive, right-click the mouse, and click on the extended volume.

<>6. Click Next. On the Configure Space page, click Next.

Memory is one of the most important components of a computer, and it is the bridge that communicates with the CPU. The running of all programs in the computer takes place in memory, so the performance of the memory has a very large impact on the computer.

Video memory, also known as frame buffer, is used to store render data that has been processed or will be extracted by the graphics card chip. Like a computer's memory, video memory is the part that is used to store the graphic information to be processed.

Go to the BIOS, find the graphics card settings option, and find that the default setting in the "Onboard VGA Share Memory" column is Auto, which means: the memory settings of the graphics card share are automatic.

After pressing "Enter", there are auto, 8MB, 16MB, 32MB, 64MB 128MB 256MB, etc. in the pop-up selection bar, so that the memory occupied by the integrated graphics card is adjustable. , set it to 256MB or higher, and press F10 to save to exit.

After the system is successfully started, right-click "My Computer", and in the pop-up properties dialog box, you find that the memory capacity has changed, which is successful.

Regarding the memory settings.

512 memory, the video memory of the integrated graphics card is adjusted to 64MB

It is 1G of memory, and the video memory of the integrated graphics card can be adjusted to 128MB....