CCleaner Cripples Application Load Times

[Abraxas]

Pretty sure this han't been posted here yet.
http://www.populartechnology.net/

Recently CCleaner has added an internet urban legend as a cleaning option, "Old Prefetch Data". Cleaning the Prefetch folder is an internet Myth that simply will not die due to the gross ignorance of many people in regards to how Windows XP Prefetching works. These same people generally recommend other bogus advice such as disabling Windows Prefetching completely and adding /Prefetch:1 to desktop shortcuts.
"Bottom line: You will NOT improve Windows performance by cleaning out the Prefetch folder. You will, in fact, degrade Windows performance by cleaning out the Prefetch folder."
CCleaner for the most part is a good application, it quickly and easily removes temporary and unused files from Windows. It has a nice interface that clearly shows what has been "cleaned". On neglected systems this can free hundreds of Megabytes of harddisk space. Apparently in the authors quest to clean everything and anything, he blindly ignored how Prefetching works.

SOURCE
I don't know that I agree that cleaning Prefetch Folder once a month is wrong  In fact on this very Forum I've read that It's not a bad thing. I do it ! What's your opinions Evangelist's ?

[szc]

Hello Abraxas,

Started by UncleRob:

http://techrepublic.com.com/5208-11183-0.html?forumID=5&threadID=178204&messageID=1813903


Continued... Very nice article Ed Bott:

http://techrepublic.com.com/5208-11183-0.html?forumID=5&threadID=178204&start=0

As Ed Bott has frequently written:
Do not clean out your Prefetch folder!

http://www.edbott.com/weblog/archives/000743.html

Here is an excerpt from Ryan Myers, a developer on Microsoft's Windows Client Performance Team:


XP systems have a Prefetch directory underneath the windows root directory, full of .pf files -- these are lists of pages to load. The file names are generated from hashing the EXE to load -- whenever you load the EXE, we hash, see if there's a matching (exename)-(hash).pf file in the prefetch directory, and if so we load those pages. (If it doesn't exist, we track what pages it loads, create that file, and pick a handful of them to save to it.) So, first off, it is a bad idea to periodically clean out that folder as some tech sites suggest. For one thing, XP will just re-create that data anyways; secondly, it trims the files anyways if there's ever more than 128 of them so that it doesn't needlessly consume space. So not only is deleting the directory totally unnecessary, but you're also putting a temporary dent in your PC's performance.

http://blogs.msdn.com/ryanmy/archive/2005/05/25/421882.aspx

Date: 07/20/05

It looks after all that cleaning of prefetch folder doesn't do any good and/or significant increase in system performance... better to listen to developers of our OS.

Cheers !

[Eddy]

better to listen to developers of our OS.

I can't sop laughing. Reminds me of a msg I sometimes get "Put the cd in the floppy drive"
Yes that is what the devellopers try to make me do!
I reported this to MS while I was still using 98 first edition, in ALL windows versions released after that, MS still haven't corrected it. So should we listen to the devellopers or should they listen to people who really have knowledge about system......

I also was able to do things that MS said was impossible with Windows......
Makes you really think heh......

1) get a stopwatch
2) boot your system and messure teh time it takes
3) move the prefetch files to another folder
4) repeat steps 1 & 2
5) does it make a difference?
Answer: no it doesn't

1) get a stopwatch
2) open applications that have a prefetch file and messure the time
3) move the prefetch files to another folder
4) reboot (to release the memory, needed for a reliable comparison)
5) repeat steps 1 & 2
6) does it make a difference?
Answer: no it doesn't

Conclusion:
Prefetch files only take up space on the drive and do not contribute anything to better system performance.

[szc]

Haha, now you make me laugh my ass off... have you read this:

So, first off, it is a bad idea to periodically clean out that folder as some tech sites suggest. For one thing, XP will just re-create that data anyways; secondly, it trims the files anyways if there's ever more than 128 of them so that it doesn't needlessly consume space. So not only is deleting the directory totally unnecessary, but you're also putting a temporary dent in your PC's performance.

[darth.mikey]

Haha Eddy read what Sasha wrote!

[Lisandro]

I don't know that I agree that cleaning Prefetch Folder once a month is wrong  In fact on this very Forum I've read that It's not a bad thing. I do it ! What's your opinions Evangelist's ?

As far I could know, Prefetch really has a very little impact over performance.
The problem is that 'every single' exe file is prefetched and the folder has a lot of files that won't be even checked anymore.
Cleaning it from time to time could get back the sanity in your HDD. Don't do it that often, it will be useless like Sasha said.
By the way, there are tweaks to fully disable prefetching... Is anybody interested?

[TedNelly]

 

Mark Russinovich Wrote
Prefetching is a good thing, leave it alone. In addition well written disk defrag utilities such as Raxco’s Perfect Disk use the layout.ini information for its optimizations.

Windows defrag also uses this file

[szc]

Unbelievable wonderful !

Mark Russinovich... SysInternals... I believe he knows his business, and he knows it very well  Who to trust if not him ?   

[darth.mikey]

Just read the links about prefetching Sasha gave you these are from guys that know what they're talking about!

http://www.edbott.com/weblog/archives/000743.html

http://blogs.msdn.com/ryanmy/archive/2005/05/25/421882.aspx

[darth.mikey]

Unbelievable wonderful !

Mark Russinovich... SysInternals... I believe he knows his business, and he knows it very well  Who to trust if not him ?   

I certainly believe him more than Eddy who has just proven he hasn't got a clue about what his talking about 

[Negeltu]

It is NOT necessary nor is it a good idea to clear the prefetch files.  Just pointless thing to do without any real gain.

[szc]

I am sure after all this, guy who is developing ccleaner may have second thoughts... maybe he will remove Clean old prefetch data from next update... or not ?

[bob3160]

Unbelievable wonderful !

Mark Russinovich... SysInternals... I believe he knows his business, and he knows it very well  Who to trust if not him ?   

If I didn't trust Mark Russinovich, then why would I have so many of his utilities.
Sorry Eddy this time I have to go with the majority opinion. I still thing that your HiLoA program is topps.

[FreewheelinFrank]

CCleaner is only a tool: you don't have to tick all the boxes. Much of the information we have the option to delete may in fact be useful to the OS or application that saves it. The internet cache speeds up browsing, and its size is limited anyway. names of last files opened in Word may be useful to record.

Some of the information is only a privacy risk. Most programs limit the size of caches. I think the real junk problem is Windows which can be over-cautious about temp files and allow them to build up.

Some viruses can also live in some of these locations so it's useful to have a tool like CCleaner to clean them out: internet cache, Java cache and temp folders. I think there was a thread where somebody mentioned a virus hiding in the Prefetch folder. In a case like that CCleaner could be used to clean out the folder.

I've had the prefetch box ticked for a while in CCleaner and haven't noticed any slowdown. Reading the above I have unticked it. I don't think CCleaner can be criticized for having the option to clean prefetch files, but it doesn't seem to make any sense to routinely remove them.

[Lisandro]

Just pointless thing to do without any real gain.

I won't say so...
Every single executable generates a prefetch file: the temporary ones, the setup files, the windows updates, etc. etc.
It's useless to keep old prefetch files, old versions never run again.
You don't have to clean them frequently but I will not say never.
The same with VRDB: you should generate them to have a database for virus recovery but not that often or you will only store infected stuffs.

The virtue is in the middle: no fanatisms and no paranoids