How is the Perfetch folder used by Windows? Prefetch what folder can I delete
It is difficult, without being a specialist, to follow the development of the Windows operating system. But there are elementary concepts that every user should understand. Knowing which folders and what they are responsible for in Windows will make it easier to navigate the system. An example of files unknown to us is the contents of C:/Windows/Prefetch.
Purpose of the folder
Let's answer the question: why do we need the Prefetch folder? At startup, Windows analyzes programs that we often use (open on our own or using startup). The system then creates information about these programs, which it stores in special temporary files in the Prefetch folder. The next time you turn on Windows, these files speed up the loading of the OS.
The OS component is responsible for doing this work. If they are removed, no changes will occur. At the next start, Windows will again collect up-to-date data about programs and place it in the Prefetch folder. In this case, loading the OS may take a little longer than usual.
Prefetch was first used on Windows XP. With the advent of Windows Vista, the folder was supplemented with SuperFetch technologies (responsible for analyzing frequently launched applications) and ReadyBoost (responsible for increasing performance). You can find it along this path: C: / Windows / Prefetch.
Managing the Prefetcher Service
You can manage the operation of the Prefetcher service in the registry editor:
This parameter operates with values from 0 to 3, which mean:
- 0x00000000 - disable component;
- 0x00000001 - acceleration of application loading;
- 0x00000002 - speed up Windows startup;
- 0x00000003 - acceleration of OS and application loading.
The default value is 3. In order to disable the service, enter the value 0 and restart the PC.
Important! The developers made sure that the Prefetch folder does not accumulate files (and gigabytes of disk space), creating a limit of 128 trace files.
Answers on questions
Is it possible to delete the Prefetch folder and the data that it stores?
No. This doesn't make sense, for three reasons: 
Some users who like to rummage through the system directories often come across the Prefetch directory. What kind of folder is in front of the user in this case, not everyone knows. Let's try to fill in the gaps in knowledge about what this directory is for and what data it contains.
Prefetch: what is the folder
Consideration of the issue will begin with the presentation of theoretical material. At startup, the operating system monitors the boot process, saving all data about it to speed up the subsequent launch in the Prefetch directory. What is the folder in front of us?
In fact, on the computer's hard drive, containing up-to-date data, parameters and components of the full cycle of system boot and launch of the most commonly used programs.
In order not to load all the components from scratch next time, Windows uses the data stored on the hard drive. Some users, however, claim that for each subsequent start of the system, the information stored in the Prefetch directory becomes outdated. Therefore, from their point of view, from time to time it is necessary to clean up the Prefetch directory. What is the Prefetch folder, a little clear. But not all cleaning enthusiasts know that the data in it is overwritten automatically after each start or launch of the application.
Let's look at the practical side of the issue of deleting its contents. A little later, it will be said how to disable the use of the download acceleration function, if this bothers someone too much.
Prefetch folder in Windows 7 and above: should it be cleared
Deleting data from this directory will not cause any critical changes in the operation of the system or installed programs.
But all those who claim that after deleting information from this directory, system boot and application launch will become faster are absolutely wrong. Quite the contrary, because the system or program will have to re-run its own modules, placing them in the operating system or computer device, and this takes time. Using data from the Prefetch directory reduces the time spent on these processes significantly. Therefore, by and large, it is undesirable to deal with cleaning, all the more so - deleting the folder itself.
It is important to understand here that during subsequent downloads, process data will still be saved. So the cleansing and removal will turn out to be what is commonly called "Sisyphean labor."
Managing Prefetch Catalog Content
If someone does not need this service, you can get rid of it. To do this, enter the system registry editor (the regedit command in the Run menu, called by the Win + R combination).
Here you need to select the HKLM branch, and then through the system catalog (SYSTEM) and the settings for the current control parameters (CurrentControlSet) go down to the memory inspection section, where the desired PrefetchParameters directory is located. It contains keys of the format 0x0000000z, where "z" can take four possible values:
- 0 - complete shutdown;
- 1 - acceleration of only the launch of programs;
- 2 - optimization of Windows boot only;
- 3 - activation of the function in full (both for the system and for applications).
The same settings can be made in the Group Policy Editor or in the Computer Administration Toolkit.
It remains to add that the directory is located in the system partition along the Windows/Prefetch path. What kind of folder and what it is for, I think, is already clear. As a last word of advice, it's best not to clean up the contents of a directory or change the default service settings on your system.
Now about another useful feature, its name is Prefetch.
This feature is designed to optimize the download of applications that you download. So that the next time they load, they load faster.
If I remember it right.
It would seem, why should we touch it?
The fact is that over time, a lot of files accumulate in the Prefetch folder from those applications that you started. And if, in addition, something was installed and deleted, then the files in Prefetch from the remote programs remain. And it starts to slow down the system.
Since when the system boots, windows tries to find all the files that appear in Prefetch.
There is no unequivocal opinion on what to do with it, someone advises deleting it, clearing this folder at each boot, someone cleaning it once a week, most users advise turning it off altogether.
But, this function is certainly useful.
The only thing is that you can clean it, if you have the ability to install and remove different programs, and you can do it once every two weeks.
If you just use already installed programs, you can sometimes clean it up when you remember. :)
The same files, or rather, their common denominator - the \Windows\Prefetch\layout.ini file - is then used by the defragmenter to optimize the location of files on disk, which further reduces the boot time.
If you are not confused yet, then Prefetch is a built-in optimization function.
What she does?
This feature is designed to reduce the loading time of applications, those that are loaded at system startup and those that you often use.
So, Prefetch contains files from the most frequently downloaded programs, sometimes not from frequently downloaded ones. By what principle windows selects them I do not know. Maybe as God puts on the soul.
And then windows waits until you leave your computer and go to smoke, drink tea, etc. I don’t remember exactly after what time, in my opinion after 20-30 minutes of inactivity of the machine.
Windows, according to the data in the Prefetch folder, begins to shuffle programs that are often used to load them faster to the beginning of the disk.
Just like I mentioned, it optimizes the loading of programs, in addition to moving them.
But often when optimizing their system, users unwittingly disable this feature.
The fact is that for the normal operation of this service, three things are needed that are often turned off. Or rather, two of them are disabled.
1. Built-in defragmenter
2. task scheduler
3. Doctor Watson (although I don't remember exactly).
It is advisable to remember this.
So what else can we do.
1. Delete either all files from this folder or files from those programs that are already missing on the machine.
2. find HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\PrefetchParameters\
There is a key EnablePrefetcher(REG_DWORD)
Values apply to it (0, 1, 2, 3)
0 - disabled (Recommended for low-power computers)
1 - recommended for computers with RAM up to 256MB (Programs only)
2 - For those who have 512MB or more on board (programs and system libraries)
3 - This is already calculated for super-duper powerful processors + at least 512MB of RAM, although with LargeSystemCache=1 it works fine on 256MB of RAM.
I recommend EnablePrefetcher=3
"Enable"="Y"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Dfrg\BootOptimizeFunction
"OptimizeComplete"="Yes"
There is one legend circulating the expanses of the network.
That in Windows Vista all applications will run and run 15% faster than in Windows XP. So you don't have to wait for the release of Windows Vista to experience all the delights of this cartoon, because. they are already included in WinXP SP2!!! It remains only to turn on this cartoon (Super Prefetch). This cartoon works ONLY under Windows XP SP2!
HKEY_LOCAL_MACHINE\SYSTEM\ CurrentControlSet\Control\Session Manager\ Memory Management\PrefetchParameters\
1. Create a type parameter
DWORD
Value Name: EnableSuperfetch
Value: 1
2. Someone says that you need to create a separate partition.
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\
Create a section Prefetcher
Create a type parameter
DWORD
Value Name: EnableSuperfetch
Value: 1
Opinions are divided, there are comments about the myth of this parameter, there are those who have noticed an increase in performance.
In any case, to check. You have nothing to lose and nothing to gain except an extra entry in the registry.
P.S. If someone has a beta version of Vista, Kindly export the branch HKEY_LOCAL_MACHINE\SYSTEM\ControlSet\Control\Session Manager\Memory Management
And send it to me if you don't mind.
Removing unnecessary files
You know, I never understood the purpose of the Temp folder in Windows. I mean, I don't know why it is needed and what it does. For example, if the installation of the program failed, then some files are copied to this folder that are not needed later, you can simply delete them without causing any harm to the system. If a failure occurs, be sure to check the Temp folder, you will probably find a lot of files in it that take up precious space on your disk.
The Temp folders are located in two locations: C:\Windows\Temp and C:\Documents and Settings\UserName\LocalSettings\Temp. By default, the Local Settings folder is hidden, so to see this folder, you will have to enable the corresponding option. Now go to these folders and delete all content.
If you have not opened these folders before, you will probably be shocked by what is going on in them.
What is Prefetch Folder
The Prefetch folder is located in the Windows system folder; it contains information about frequently opened programs for quick access to them. It is used to speed up the loading of the operating system and the launch of programs.
When you start your computer, Windows monitors the boot process. After that, the received information is saved to the hard drive in the Prefetch folder. The next time you start, this information is used to speed up the loading of the operating system. The same thing happens when you start any program.
Clearing the Prefetch Folder
The developers at Microsoft decided that the Temp folders take up too little of your disk space, so why not create another folder that does the same thing? Thanks a lot! No, really, thanks.
We probably have very few folders that just eat up free disk space. Now, in addition to the Temp folder, we have a wonderful Prefetch folder. This folder functions differently than the Temp folder, but like the Temp folder, it can hold junk for centuries if you don't manually delete it. Therefore, I advise you to periodically clear this folder (C:\Windows\Prefetch). And do not worry, the system will not suffer from this. Any deleted files that Windows needs will be automatically recreated.
Hello dear friend! Most recently, we considered the topic of deleting temporary folders. There I talked about various folders, including Temp, in which garbage accumulates over time. These junk files need to be cleaned. and published, but as it turned out, not all. I found an interesting folder that many saw, but were afraid to delete something in it. This folder is called "Prefetch" and is located inside the Windows folder. What kind of folder and why you need it, you will find out below.
What is prefetch?
Let's turn to the global repository of knowledge - Wikipedia. She says:
Prefetcher- a component of the Microsoft Windows operating system that speeds up the process of its initial loading, as well as reducing the time it takes to launch programs. Prefetcher first appeared in the Windows XP operating system. Since Windows Vista, it has been supplemented with SuperFetch and ReadyBoost technologies.
It turns out that this system monitors which programs you use most often and writes them to a special folder: C:\Windows\Prefetch
All sorts of different files are stored there with incomprehensible extensions like this.
Well, in general, the Windows loader, analyzing these records, drives the software into RAM in advance, in order to then speed up the response to your request.
By default, entries in the prefetch folder are made not only by system, but also by secondary applications, and this slows down the download. It is necessary to make sure that only information from system files is written to the folder.
With a hot combination of Win + R, we activate the command input window, and enter regedit.
In the registry editor, look for the following branch:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SessionManager\Memory Management\PrefetchParameters
In the right window we need to change the parameter EnablePrefetcher.
RMB select "Change ..".
The default is three. "3" says that both system processes and various kinds of applications are running. If we put 2, then we will start only system processes. If 1 - only applications, and 0 - generally disable.
Let's do a double!
We confirm the changes by pressing the OK button.
Summing up
With such simple manipulations, we have at least slightly optimized our Windows!
