Good idea! At the cost though, I would think, of a CPU overhead for on-the-fly decompression when those files are required. I take it this is why you advise to only do it on seldom-accessed files?

Last edited by Triple-E Wannabe (2007-10-31 6:05:12 am)

Triple-E Wannabe wrote:

Good idea! At the cost though, I would think, of a CPU overhead for on-the-fly decompression when those files are required. I take it this is why you advise to only do it on seldom-accessed files?

File compression slows down file access for that compressed file in particular. The is a lag time between file access and file execution/reading because the CPU has to decompress the file before being able to access it. That is why files that are commonly used (.exe and .dll) should probably not be compressed. There are however lots of files in Windows that you may want to keep. For example, the files in c:\windows\system32\dllcache are almost never accessed, but are still quite essential in case you computer crashes while you're away from home and don't have access to your Win CD. I have therefore compressed these files.
Other exemple of files that you may want to compress are .hlp files. I never read help but once or twice a year, I need to read them so I can compress these files without everyday performance slowing.
If you compress completely Windows's folder, then you'll run into serious performance issues.

Compression can even encrease performance (less data to read), so I use it and it works like a charm.

Molly wrote:

care to elaborate on how drive compression will affect the amount of data to be read?

I think that I can see both of your points?  Of course, in the end the amount of data must be exactly the same with lossless compression( necessary in this case), but the amount of data transiting the medium interface will be less by the amount of compression. That is why it is used in some serial data link protocols.  However, for any possible speedup to occur the decompression time would have to be shorter than the time for uncompressed data to cross the data link.  Perhaps it would speed up a USB connected FLASH read, but I would expect that the SSD read would be fast enough to probably make the decompression phase the actual bottleneck?

--Dave

Well assuming we don't want to compress the entire drive, it would be a good idea to make a list of the folders that are rarely accessed to be compressed.  For example.

C:\windows\inf
C:\windows\ie7
C:\windows\ieupdates

Hi to all,

in my Italian Xp pro, i dont find such choice. WHere i do mistake?




thanks

You need WinXP with service pack2 and all the latest updates.

Fluffywings wrote:

C:\windows\ie7
C:\windows\ieupdates

You can essentially delete these two folders if you do not plan to rollback to ie6.

After you have deleted these two folders, use ccleaner to clean out the uninstaller registry related to ie7 uninstallation.

I compressed the whole drive including system32 folder.  Some files did not compress, I suspect because they were in use at the time or windows prevented it. 

I have encountered the occasional problem where dll calls have failed.  I found that I needed to uncompress the following ddl's:  wiashext.dll, asycfilt.dll and shgina.dll.  There may be more that I have not come aross before.

Has anyone encontered any similar problem?

I have not particularly noticed any severe performance penalty.

Welcome to the forums, rodneyh.

I have also compressed the whole C: drive and haven't encountered any problems.
No noticeable slow-downs either (2GB ram).

treare wrote:

Hi,

Compressed whole c: on my eee. Overal it indeed doesn't slow down but sometimes opening things has a small delay though.

Hello treare,

I personally think a fraction of a second delay in opening certain files is not a bad trade-off considering the gain in space.

in the end, it's all about personal preferences, but file compression does cause an increased CPU usage (up to 3%) which has an impact on the battery life time and overall system performance. file compression also will increase the number of write requests on the SSD by 25%.

implications that have been acknowledged and addresseded by Microsoft recently in their 'Guidelines for Designing Flash-Based Ultra Low Cost PCs for Windows XP".

http://download.microsoft.com/download/ … SFT%20.pdf

Last edited by Molly (2008-05-15 11:10:56 am)