Compressing the C: Drive

When you right click the C: Drive and select properties, there's a checkbox for "Compress this drive to save disk space." What will happen if I check it and apply? I'm asking this because I'm running short of space. Will the system remain stable and will I be able to access the files in the C: drive?

 

I'm guessing that my description of the compressing the hard disk will be a bit crude, but here I go.

I'd expect some serious slowdown, in everything. What comes to mind for me is that everything is pretty much a ZIP file, and we all know how slow ZIP files can be to open and extract.

I could be wrong, but that's my interpretation.

Greg

 

The option to compress your HDD should be a last resort kind of thing. Once you compress it, your whole system will boggle down because it then has to read the compress data and then uncompress it. It is also known cause data corruption as well. I wouldn't recommend it. Besides, you really don't save that much space.

HDD space is very inexpensive these days. You could always invest in an external HDD as well.

 

It will remain stable, although you may experience some slowdown. Also, compressing the entire disk can take hours is you have alot of data inside it.

 

It will result in more CPU usage because your comp will have to decompress every file once you access it.

 

Do not compress the C drive, it will slowing down your system. Because it takes time and resources to decompress all the system file that used by Windows...

 

Forget compressing! It will only cause more slowdown!

Just go out there and get you an externam hard disk.

Make sure you delete all the files in your c:\Documents And Settings\your user account\Temp

 

Contrary to what everyone has already said, it is possible that compressing can SPEED UP your system in some situations. However, compressing the ENTIRE C: drive is a bad idea.

The first thing you should do is find out what's eating all of your space. Use "WinDirStat" to do that. Also take a look at my guide "Where's my disk space going" (in my sig). Once you have done that, target the areas that windirstat says are taking the most space. Note that compressing video and music files will not gain you any space, because they are already compressed.

You can probably get away with compressing Program Files, which is where I would guess a lot of space is being used. Start with some of the bigger folders, then go down from there. If you have a lot of games, however, you will probably see a performance hit when playing them.

Now, back to the performance thing... the thing is, your CPU will have to compress/decompress files every time you use them. This can cause a performance loss, if your CPU is already running at 100%. If your CPU is idle, it will use some of those cycles, but you probably won't notice the slowdown. You may notice a drop in battery life though.

As for other performance, you also have to take into account that because the data will be compressed, there will be less of it going to and from the hard disk. In this case, it's possible you can get a performance increase because now the data can be effectively read from/written to the disk faster (because there is less of it). So if you are doing a lot of IO with compressable data (like text), and don't have a high CPU load, then it may be a benefit.

 

I totally disagree with you, but to each his own I guess.

 

I know you disagree, because you only go with your gut instead of analyzing how things actually work and making conclusions based on that information. I know, it's more work, so making assumptions and giving everyone advice based on them is the better way to go.

 

I won't reply to you coz if I do I would only be lowering my level to yours and having you beat me there! You think what you want. I know i'm the pro.

kthxbye

 

COMPRESSION = MORE CPU UTLIZATION = SLOW

bye

 

Only if your application is CPU-bound, and with today's dual core systems, it's very unlikely unless you are compressing video or something like that. We've had disk compression for at least a decade (stacker on DOS), and CPU speed has increased exponentially since then.

Most of the performance problems during zipping/unzipping files come from I/O, not the CPU processing the data.

 

Hmm. Don't know whether or not to do it yet... But just increased disk space to 60 GBs by cleaning restore points from 40 GBs, so that's not too bad.

 

Get CCleaner here and perform a cleanup...that should help too !!

 

OK, so I did some benchmarking to get an idea of what the performance differences are for compressed vs. non-compressed file systems. These tests were done using exactly the same hard disk. First I ran them on the uncompressed drive, then I enabled compression and ran the tests again.

First I used HD Tune, and here are the results:
Uncompressed drive:


Compressed drive:


So the compressed drive has a slightly higher burst rate, but also a slightly higher CPU usage, but otherwise they are virtually identical.


Then I tested with Sisoft Sandra using the "File system" test. The tests we are interested in are the results in red, the "Current drive".
The uncompressed drive:


and the compressed one:


The compressed drive had a higher throughput, as well as faster reads. However there was a performance hit when it came to writing to the disk. Also the access time went down with compression enabled.

So there you have it, in some cases compression can be faster, and in others it can be slower.

 

Good going orev! Thanks for the benchmarks. I actually expected that kind of behaviour. I also think that I am going to compress my e: disk which is strictly holding games since I have noticed that gcf files that are created by Steam are not compressed in any way. So I expect at least 30% more free space and games are read usually into memory, so no too much writing there. I will report my findings in another thread.

Cheers,

Ivan

 

Concrete data > opinions

Thanks for the benchmarks, orev.

 

Hey Orev, I don't want to be too much of a bother, but could you please do some gaming benchmarks to see if it will have an effect on gaming?

Thanks,
Leon

+Rep!

 

I don't do much/any gaming, but most of the gaming benchmarks I've seen mostly test the graphics card, CPU, and maybe memory. If you have an idea of one in mind that will test the disk, please let me know.

Otherwise I think we can extrapolate that there would be a small amount of CPU used (few percent based on the HD Tune tests), so if the game is CPU-bound, then it might have an effect. If you have a dual-core system, the game would have to be using both cores. But based from what I know, most games are GPU-bound, and I think are optimized to read data into memory, so you wouldn't have to be waiting for it except when a new level is loading.

 

I have Core 2 Duo and 2GB ram and so far no issues with games whatsoever. I will test it a bit more to see if I see any bad sides of compressing the volume that holds Steam gcf files.

Ivan

 

orev, great idea with the benchmarks. Yes, indeed there is no performance difference when compared to a non-compressed drive.
I used to have C compressed, but finally gave up on that idea, since I didn't gain much space and never really felt like wasting some time for everything to get compressed.
I wouldn't advise you to compress a folder or a drive with music, movies and other already compressed files (unless it's full of uncompressed files) as it wouldn't help at all (it will get you the same size).