Why does disk cleanup compress old files

The absolute exception is very small files, but files that are compressed anyway, in ZIP or MP3 format. You may not notice any acceleration, mainly because you considerThis option only affects DLLs and system files that have not been viewed recently so it is very likely that you will not need it in the future.

Is it worth it? As always, it depends on the circumstances. I just enabled and cleared the Compress Old Files routine for the hard drive, I upgraded from 1. Compressing such a disk will not change anything. DivX, MP3, etc.

All this leads to the shutdown of your PC. In the search box on the taskbar, select Disk Cleanup and select Disk Cleanup from the list of results. Select our drive that you want to properly clean up and then click OK.

In the Files section, to make sure you delete them, select the file types that will make it easier to delete. For a good description of the file type, continue.

Create a free Team What is Teams? Learn more. Asked 12 years ago. Active 3 years, 7 months ago. Viewed 47k times. Improve this question. Peter Mortensen Mehper C. Palavuzlar Mehper C. Palavuzlar Add a comment. Active Oldest Votes. The more precise description from the The Elder Geek here is: Unlike the other categories, Compress Old Files doesn't delete any files from the drive. Improve this answer. BinaryMisfit BinaryMisfit Pro - you save space.

Con - when you access those files they need to be decompressed, so access is slower. Neal Neal 8, 1 1 gold badge 27 27 silver badges 33 33 bronze badges. They need to be decompressed, but with the difference in speed between CPU and disk being ever greater, the time to read additional blocks of the file from disk will be in most cases except very small files actually greater than the time to decompress the file.

Especially so if the disk is fragmented, and it needs several seeks to read the file. So I don't really see any cons to turning off the compression.

Except, if you want to fine-tune it, very small files and files that are compressed anyway, such as ZIP, MP3 etc. Luis Luis 11 1 1 bronze badge. Same for me as well. We run the command quite often here on our server systems and my team has a lot of them. We often saw that a server running since years get arround 20 GB free space from a 50 GB disk when the comand is run.

Sure it might take CPU to de-compress the file, but if it keeps us from enlarging the diskspace in the next years who care about that less CPU. Server Fault is a question and answer site for system and network administrators. It only takes a minute to sign up. Connect and share knowledge within a single location that is structured and easy to search. What are the pros and cons on compressing old files on a disk?

I've read that compressing old files will degrade the performance when accessing the compressed files. I've got gigabytes of old files in my laptop; is it worth the trade-off? Compressed files makes a big difference when you have a bunch of small text files like source code, batch scripts, etc. So your mileage may vary. Instead of letting Disk Clean-up compress your old files, instead use Windows Find Files and look for files over a certain age by type. Then compress or delete those. If you need to free up space though I recommend using WinDirStat.

It will show you where you are using the most space. Especially with a "playground machine" like you have, you may be surprised that you still have an old install of Oracle kicking around that you forgot about, or a database instance leftover from the time you experimented with storing really large image files in a DB.

Since it helps you to target your cleanup efforts where there is the most space being taken up, you get more results quicker. It can also show you if you have a directory filled with a lot of small files, which might be a good candidate for compressing. Disk time is expensive, processor time is cheap. Compressed files can be read faster than uncompressed ones they are smaller , and on modern machines there should always be enough processor time available to decompress them on the fly.