Memory committed bytes commit charge when a process

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Memory committed bytes (commit charge) When a process runs, the operating system assigns memory to the process. The amount of committed memory identifies how much memory has been assigned to running processes. Be aware of the following conditions indicated by this statistic: If the value exceeds the amount of physical RAM, then the page file is being used instead of physical RAM. At some point, this will start to cause a bottleneck. To temporarily make more memory available, quit running programs or increase the page file size. However, the only permanent solution is to add more physical memory. Page file usage The page file usage identifies the amount or percentage of the page file that is being used. A common recommendation is for the page file to be 1.5 to 2 times larger than the physical memory. In most cases, you will let the system manage the page file size. It is normal for the page file to show some use, even when the system has sufficient physical memory. When the page file use percentage is near 100%, you can increase the page file size as a temporary measure. Adding more memory is the best permanent solution. Memory pages per second The operating system allocates memory to processes in 4,096 KB blocks called pages . Instead of assigning physical memory addresses, the operating system assigns virtual memory addresses
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to shield the process from the details of the physical memory storage system. The paging supervisor is a process that maintains a table that correlates virtual memory addresses with the actual physical memory locations. When physical memory is low, data in RAM that is currently not being used by the CPU can be moved to the hard disk in order to free up memory for other processes. The area on the hard disk used for storing the contents of RAM is called the page file . When the CPU needs to access data in RAM, a page fault (also called a hard fault ) occurs when that data does not exist in RAM but is instead in the page file. Paging is the process of moving data from RAM to disk and back. Before the CPU can work with data required by a process, that data must be placed into RAM. The memory pages per second statistic identifies the number of hard faults that occur each second. A high number for this statistic accompanied by high disk activity (% Disk Time or the disk activity light constantly flashing) could indicate a condition known as thrashing . With thrashing, the demand for memory and the low amount of physical RAM means that the system must be constantly moving data from RAM, to disk, and back. The negative effects associated with paging increases as the amount of memory increases past the amount of physical RAM. While some paging is normal, as the demands on memory increase, the amount of paging will at some point reach a point where thrashing occurs and the effect on performance is noticeable--even to the point of making the system unusable.
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