Why do hard disks work frequently when your computer is idle?

In the process of using Windows, many people may find the problem: when the computer is idle for a period of time, even if there is no big program running, the hard drive light is flashing frequently, it seems that the system is busy processing some data. Some people think their systems are poisoned, but that's not the case, probably because some of Windows ' backend services are causing it.

Many of the features in Windows require a large amount of data to be processed in advance, and if the user is using the computer, this will undoubtedly affect the normal use, so some processing work will be scheduled to occur automatically in the background when the system is idle. This situation mainly exists in the following two functions: The Disk Defragmenter that Windows brings up automatically runs at a certain time by default, so that you don't have to pay attention to the defragmentation of disk fragments, because the collation can be done automatically with the user inadvertently, to ensure better read and write performance.

In addition, Win7 's file search function also needs to be indexed in advance for the files being searched, and future searches can be done in the index database, so the search is faster and more accurate. However, depending on the content and number of files being indexed, indexing may take some time to complete. When you create an index, the performance of the system is greatly affected.

In fact, this problem has been taken into account in the design of Windows. Before the computer hardware performance is not strong enough. Typically, a user can run only one or two programs at a time, and now many people are accustomed to opening more than 10 or more programs at the same time, and other programs will run in the system background, in addition to the programs currently in use. With so many programs running at the same time, this can easily lead to a problem: contention for resources. There are several types of resources here, such as CPU resources, memory resources, disk I/O resources, and so on. Now the CPU speed is getting faster, the core is more and more, and the new computer memory is more and more, so multiple programs running at the same time for CPU and memory resources contention is not serious, on the contrary, the contention for disk I/O resources is more serious.

For example, almost everyone in the system needs to install anti-virus software, and turn on real-time monitoring, this feature will real-time scan the user to access each file. So if anti-virus software is scanning files, and users are doing more disk read and write activities, such as compressing or encrypting files, and handling large amounts of fragmented data, this can lead to serious conflicts.

And many people imagine that, even if you run multiple programs at the same time, there can only be one program to read and write to the hard disk. If more than one program needs to read or write, other reads and writes are scheduled into the queue, and the requests in the queue are processed sequentially. In older versions of Windows, disk reads and writes are not prioritized, that is, if the anti-virus software is to scan files on the table and the user is to process a file in the foreground, both programs will be treated equally. In fact, this approach is not good, because anti-virus software running in the background, even if slow is not easy to detect, and the program used in the foreground if slower, it is easy to detect, but also reduce operational efficiency.

A new set of I/O priority features is added to the win7 system download. In short, all programs running in the foreground will have higher priority disk read/write I/O, and the programs running on the latter have lower I/O priority. This way, if both the foreground and background programs need to read and write to the hard disk, the system will prioritize requests for the foreground program. Therefore, in theory, even if there are many programs need to read and write the hard disk, the impact of the foreground program will be minimized.

Return the topic to the two features mentioned above. In fact, these two functions on the performance of the system is far less serious than many people think. First, these two features are implemented through the system daemon, so their own I/O priority is very low and has little impact on other foreground programs. Also, by default, these features are only available when the system is idle (for example, at noon or lunchtime), and once the computer is reused, these processes automatically retire to the background and continue to run at lower priority levels. If you need to run some of the larger programs, these background processes will automatically suspend processing if necessary until the system starts to idle again.

Therefore, a more effective suggestion is that if you do not use the computer for two hours, you may want to idle the computer, rather than shutdown or sleep, so that the system can use this time to process the background process. Using a two-hour process for a more fluid experience is a good deal.