G
Guest
how do I turn off the autodefrag feature. I do digital recording and don't want it to run while I record.
R
Rocket J. Squirrel
Windows XP performs a partial defrag, approximately once very three days,
while the processor is idle.
Rocky
while the processor is idle.
Rocky
want it to run while I record.zep said:
S
srdiamond
Really? So what happens if you have a third party defragger that by design
imposes a certain order on the files, such as by frequency of access or in
alphabetical order, or whatever. Then Windows comes along and messes all
of that work up? Or am I failing to understand you?
This would, I suppose, provide an ironic argument for using the native
defragger.
srdiamond
imposes a certain order on the files, such as by frequency of access or in
alphabetical order, or whatever. Then Windows comes along and messes all
of that work up? Or am I failing to understand you?
This would, I suppose, provide an ironic argument for using the native
defragger.
srdiamond
B
Bill
srdiamond said:
XP prefetching and auto layout is similar to what Windows 98 does with
its defrag option to "align" the files for optimum read speed on your
drive.
If you use a defragger like Norton Speedisk, both XP and Speedisk will
move the same files around, Speedisk putting them in one spot, and XP
moving them to another spot when it does its partial defrag.
But this is only for the files listed in the prefetch folder, which is
usually just 5-20% of the files on your drive, depending on what you
have installed and what you've used the most lately.
Some other defrag programs like PerfectDisk will disable the automatic
layout and put the files in its preferred order.
Yes it would, actually.
After trying out four third-party defrag programs for real world
performance differences, I've found little reason to use a third party
defragger. The built-in XP Defrag does a pretty good job.
In fact, I've had a problem with PerfectDisk interfering with the
prefetch feature on my system and slowing things down, so I prefer to
just let XP do its own thing. You can read the thread "Perfectdisk Stops
Prefetch - Greg Hayes?" if you want more details.
S
srdiamond
I'm not sure if by "real world performance differences" you mean the
computer's performance or the defragger's. As to the first, PC World
claims defragmentation is completely irrelevant to performance. To my
limited knowledge, PC World's study is unrebutted by counter-findings in
any study using contemporary hard drives.
But there are tremendous differences in the speed of defragmentation. If
there weren't, the third party suppliers would be guilty of fraud. The
only reason I bought a third party defragger is that I set my Windows
defragger to defrag at night and by next morning it was only half done. I
have a relative small drive (40 Gig.) and a pretty new computer. Only
about a month's worth of fragmentation had accumulated.
All the third party utilities go much faster. I have an aversion to
Diskeeper because of its misleading advertising, and I chose O&O Defrag
over Perfect Disk purely on cost. But I'm glad I chose it after reading
the article you referenced.
O & O provides a lot of control over placement criteria. The rational
approach would be to choose a criterion matching or close to the one
Windows employs, but I have no idea of what that might be.
srdiamond
R
Rocket J. Squirrel
PC World's misguided advice was widely rebutted. For one example, see the
LangaList newsletter:
"Defragging Pointless?"
http://www.langa.com/newsletters/2004/2004-01-22.htm.
The truth is, a standalone Windows XP computer will almost always realize no
appreciable increase in speed by using a third-party defragger. Third-party
defraggers certainly have their place, but it's not in the overwhelming
majority of standalone computers.
For most standalone computers, third-party defraggers give users the
illusion that they are 'doing something' for their computers, when in fact
they are accomplishing nothing significant while adding complexity to their
systems.
Rocky
LangaList newsletter:
"Defragging Pointless?"
http://www.langa.com/newsletters/2004/2004-01-22.htm.
The truth is, a standalone Windows XP computer will almost always realize no
appreciable increase in speed by using a third-party defragger. Third-party
defraggers certainly have their place, but it's not in the overwhelming
majority of standalone computers.
For most standalone computers, third-party defraggers give users the
illusion that they are 'doing something' for their computers, when in fact
they are accomplishing nothing significant while adding complexity to their
systems.
Rocky
S
srdiamond
The relevant part of the LangaList article is short:
"No, I don't agree. Defragging reduces the need for the drive heads to
move all around the disk surface to pick up scattered bits and pieces of
various files. If each "head seek" takes, say, 5ms, every 200 seeks you
avoid will save you a full second--- an easily noticeable amount. (You
could save 200 seeks loading just one large file.) Over the course of a
day--- with tens or hundreds of thousands of head seeks--- it will add up.
No, the saved time won't be enough to let you go home early, but it
definitely will make your PC feel faster and more responsive!"
So, was it rebutted by another empirical study, or by knowing
generalizations? Everyone knows that a defragmented disk _should_ be
faster, it's simple arithmetic. But PC World found otherwise, by using
benchmarks instead of assumptions.
PC World failed to present any compelling explanation of its failure to
confirm a virtual platitude. But contrary to what the article claims, PC
World advised defragging, without illusions about performance gains.
BIt's foolish, however, to defrag when you want a false sense of
maintaining your computer. Everyone knows that at such times, you run a
registry cleaner!
srdiamond
R
Rocket J. Squirrel
"BIt's foolish, however, to defrag when you want a false sense of
maintaining your computer. Everyone knows that at such times, you run a
registry cleaner!"
Right on!
(Does anyone say "right on" anymore, or did I just give away my age?)
Rocky
maintaining your computer. Everyone knows that at such times, you run a
registry cleaner!"
Right on!
(Does anyone say "right on" anymore, or did I just give away my age?)
Rocky
B
Bill
srdiamond said:
The computer's performance.
I've found that occasional defragging is a good idea and there is a
slight performance boost when you haven't defragged in a while. But
there is really little need to get a third party defragger, and there is
no need to run Defrag every day or even every week. Once a month is good
enough for most users.
A server will benefit from more frequent defragging though due to heavy
disk activity.
I have first-hand experience that says otherwise.
But as I said above, defragging once a month is usually good enough.
That's not typical...sounds like Defrag is restarting.
My drive has about 80gigs worth of stuff on it, but it only takes 30
minutes give or take a few minutes, to run with XP's Defrag. I do it
manually once a month when I clean up the drive.
The first time you run defrag, it takes a lot longer, about an hour or
so on my system because it has to completely re-arrange many of the
files. But once that's done, the files are not optimized again unless
they become defragmented again, so the second time Defrag runs, it's
much faster.
But any running programs that write to the drive, causes Defrag to
re-analyze the disk and start over again. This is why some systems take
all night to run and they're still not done. When you use Defrag, it's
best to close any open programs like Word or Outlook, and if you have a
non-XP screensaver, disable it till Defrag is done.
That's because they create a map of the drive and then defrag according
to their map. They don't care about new writes to the drive and simply
place the cached data in the same spot according to the map.
XP's Defrag does things a little simpler, and as a result is slower.
In general terms, older versions of DOS/Windows used to write chunks of
data at the first free cluster, and then move to the next cluster to
write the next chunk. The XP API finds the first free available cluster
that will hold the full size of the file (up to 512megs I think **) then
writes it there in one contiguous chunk, unless drive space is limited,
in which case it puts it where it can.
Placement of files on the drive doesn't really matter as far as opening
and closing programs and data files is concerned, due to disk caching,
as long as the files are contiguous. The only reason third-party
defraggers use a specific layout, is to help reduce often changed files
from fragmenting quickly and allow faster defrag runs the next time.
This all comes down to user-perceived performance gains. The user sees
the third-party defrag run really fast, and assumes it's doing a better
job of optimizing the files for day-to-day use. That's not necessarily
correct, but it's good advertising.
** - note that even the third-party defraggers often fail to defrag
large files, contrary to general claims of complete defragmentation. If
you have a 700meg CD ISO, and it wasn't lucky enough to be written in
one chunk, it won't be defragged. This is because they use Micro$oft's
API to write to the disk, and they have to live with that API's design
limitations.
Whew...that was a long one. I hope I got it all straight.
R
Rocket J. Squirrel
The little software geek inside me is fascinated by this thread, and we're
taking notes.->
Rocky
taking notes.
->Rocky
G
Greg Hayes/Raxco Software
It depends on the 3rd party defragmenter. Using some will result in this
behaviour. Others will work "with" Windows so that this doesn't happen.
- Greg/Raxco Software
Microsoft MVP - Windows File System
Disclaimer: I work for Raxco Software, the maker of PerfectDisk - a
commercial defrag utility, as a systems engineer in the support department.
Want to email me? Delete ntloader.
behaviour. Others will work "with" Windows so that this doesn't happen.
- Greg/Raxco Software
Microsoft MVP - Windows File System
Disclaimer: I work for Raxco Software, the maker of PerfectDisk - a
commercial defrag utility, as a systems engineer in the support department.
Want to email me? Delete ntloader.