When do Delete Old Prefetch files, auto-rebuild, and layout.ini...?

[scottls]

Usually a couple of days after my Windows manual Update there are 31... old prefetch files to delete, and in-between varies...

 

1. Following deletion, when does Win7 start auto-rebuilding them..., and how long does that usually take?

I read that's at Win idle, And I should probably temp disable my KIS AV's idle scan?

 

2. Is it also a good idea to manually delete layout.ini once-in-a Great while, and when?

[dvdbane]

if im not mistaken, if you delete prefetch, it will rebuild the next startup

no need to delete prefetch because it will auto delete and auto rebuild

[mta]

as you start a program, Windows adds it to Prefetch (if it's not already there, is of a higher version and meets the caching requirements).

so deleting the entries in Prefetch will actually make some things run ever so slightly slower until they get re-prefetched.

 

it doesn't hurt to erase Prefetch as some programs may be in there that are no longer used or installed - but they will eventually work their way out of the list.

(from memory, only about 130 files are kept, give or take) (ps: that was for XP, I just checked my Win8 and there are 240 but there's a lot of same entries with different versions)

 

apologies @dvdbane for re-posting your suggestion, I thought it needed further explaining as I wasn't sure of the OP's knowledge of the background to it all.

 

 

EDIT: (forgot question 2)

as to layout.ini - personally I've deleted it and the whole Prefetch folder sometimes, back in the XP days, with no ill-effects.

but I stopped doing that action years ago. wasn't much point. all the files get rebuilt eventually, the space saving was marginal at best and there was no reason speed-wise to do it.

the main reason was for when a virus was found and it got Prefetched - then I would blow away the whole folder.

 

but to answer that question, since the layout.ini file contains entries to system locations/files, unless you know the consequences, leave it alone in my opinion.

it's a harmless .ini file, taking little space (mine is currently 1.5mb) and will get rebuilt anyway.

 

you would need to have a good reason that out ways the greater potential for things going pear-shaped.

[scottls]

as you start a program, Windows adds it to Prefetch (if it's not already there, is of a higher version and meets the caching requirements).

so deleting the entries in Prefetch will actually make some things run ever so slightly slower until they get re-prefetched.

 

it doesn't hurt to erase Prefetch as some programs may be in there that are no longer used or installed - but they will eventually work their way out of the list.

(from memory, only about 130 files are kept, give or take) (ps: that was for XP, I just checked my Win8 and there are 240 but there's a lot of same entries with different versions)

 

apologies @dvdbane for re-posting your suggestion, I thought it needed further explaining as I wasn't sure of the OP's knowledge of the background to it all.

 

 

EDIT: (forgot question 2)

as to layout.ini - personally I've deleted it and the whole Prefetch folder sometimes, back in the XP days, with no ill-effects.

but I stopped doing that action years ago. wasn't much point. all the files get rebuilt eventually, the space saving was marginal at best and there was no reason speed-wise to do it.

the main reason was for when a virus was found and it got Prefetched - then I would blow away the whole folder.

 

but to answer that question, since the layout.ini file contains entries to system locations/files, unless you know the consequences, leave it alone in my opinion.

it's a harmless .ini file, taking little space (mine is currently 1.5mb) and will get rebuilt anyway.

 

you would need to have a good reason that out ways the greater potential for things going pear-shaped.

 

Thank you for the reply, and I'm going to stop deleting old prefetch files because of issues... (I got into this habit in the old XP days)!-

 

2 days after this weeks Win Update- CCleaner deleted 26 old prefetch files (many System prefetch, along with 128mb of deleted files...).

I closely watched the Prefetch folder for rebuild dates/times?

Many didn't auto-rebuild until Late After the next days cold startup/2 restarts.

Performance became slow, and there is still No increase the 2nd day (today).

 

I also figured that there was No reason to defrag , until All the prefetch files were auto-rebuilt (compact/contiguous...).

 

BTW- My Win7 64-bit laptop has Really slowed down, after doing similar...

 

It seems that I sometimes make things worse while trying to make things a little better (i.e. JV PowerTools- Immunize...!).

I going to try and remember!- If it ain't broke, don't fix it!