D
Dave
Does disk compression slow down windows XP if I compress c:/ that contains
windows. Thank You, Dave
windows. Thank You, Dave
G
Gordon
Yes.
C
Carey Frisch [MVP]
You may notice a decrease in performance when working with
NTFS compressed files. When you open a compressed file,
Windows automatically decompresses it for you, and when you
close the file, Windows compresses it again. This process may
decrease your computers performance.
File compression overview
http://www.microsoft.com/resources/...proddocs/en-us/ff_file_compress_overview.mspx
--
Carey Frisch
Microsoft MVP
Windows Shell/User
----------------------------------------------------------------------------------------------------
:
| Does disk compression slow down windows XP if I compress c:/ that contains
| windows. Thank You, Dave
NTFS compressed files. When you open a compressed file,
Windows automatically decompresses it for you, and when you
close the file, Windows compresses it again. This process may
decrease your computers performance.
File compression overview
http://www.microsoft.com/resources/...proddocs/en-us/ff_file_compress_overview.mspx
--
Carey Frisch
Microsoft MVP
Windows Shell/User
----------------------------------------------------------------------------------------------------
:
| Does disk compression slow down windows XP if I compress c:/ that contains
| windows. Thank You, Dave
G
Gordon
Wouldn't just a straight "yes" have sufficed?
V
Vanguard
Gordon said:
Probably not. With such an undetailed question, there is likely a "why"
inferred that the OP never stated, probably because the OP hasn't a clue
what compression really is or how it works.
G
Guest
No.
K
Ken Blake, MVP
Dave said:
Compression slows down the computer because it takes time to compress or
uncompress a file every time it is written or read. On the other hand,
compression speeds up the computer, because every time you read or write a
file, there is less to read or write.
Which of these factors is more significant largely depends on the relative
speeds of the CPU (used for compressing/uncompressing) and the hard drive(
used for reading/writing), but on most modern computers, the result is
probably a near wash either way.
I strongly argue against disk compression, not becauseof its effect on
performance, but because of its effect on the reliability of your data.
Without compression, if you develop a bad spot on the drive, you won't be
able to read one or more files. With compression, all your eggs are in one
basket, and a bad spot makes everything unreadable.
P
Plato
Dave said:
Do NOT use disk compression for ANY reason.
C
Carl Kaufmann
This is not the case with NTFS compression which compresses on a
file-by-file basis, rather than the old "container" approach.
Carl
C
capitan
Plato said:
Why?
K
Ken Blake, MVP
Carl said:
My reply was based on the question about *disk* compression, not file
compression. As you say, that issue doesn't exist with NTFS file
compression.
P
Plato
capitan said:
Posted by Ken Blake:
I strongly argue against disk compression, not because of its effect on
performance, but because of its effect on the reliability of your data.
Without compression, if you develop a bad spot on the drive, you wont be
able to read one or more files. With compression, all your eggs are in
one basket, and a bad spot makes _EVERYTHING_ unreadable.
A
Al Dykes
I used NTFS compression big-time and I rarely^H^H^H^Hnever saw a
downside. This was when a CPU was measured in 100s of MHz and a GB of
memory meant it was a serious server.
I frequently saw big performance *improvements* for my data.
When we were trying to do *too much* on the desktop machines our
developers had I always compressed the entire C drive to get all the
tools to fit. Never a problem.
Today, with GHz CPUs and memory I don't see a problem.
My best case was when we got a GB flat ASCII file each day from a
stock exchange. It compressed 20:1, which was very desirable by
itself. When we benchmarked the system that read the file it ran much
faster becasue the bottleneck was the disk's transfer rate and it was
effectively 20x as fast. The CPU cycles to unpack the data were
offset by the reduced CPU cycles for the physical IO.
The *big* downside is if you try to compress a file that is database
in which data is being inserted. If you read a record, update it and
then write it, the record might compress to a slightly longer record
and really screw up the fragmentation. It's won't break, but it could
get really slow.
As a hack, I once installed a a full Oracle server on a compressed
file system. It worked.
A
Al Dykes
I've used compression on hundreds of machines, including servers, for
10 or more years, since NTFS was announnces in NT3.51 (ISTR). It
saved out bacon becuase our developers machines and 220MB disk drives
and the GUI IDEs that were comming out tended to be on the "ahem" big
side.
P
Plato
Al said:
You're missing the point. You'll see sooner or later
A
Al Dykes
You're missing the point. You'll see sooner or later
huh? I apply compression all the time, and have been for more than 10
years, to hundreds of systems. I think I would have noticed.
If you're not CPU bound during disk I/O you'll see very little effect
and it may even be a win if you're I/O-bound on highly compressionalble
data.
P
Plato
Al said:
Applied disk compression to hundreds of systems? That's a fib.
G
Guest
DONT DO IT!!! I used disc compresion on my C drive to save space and when i
tried to play a game that was on it it would not open and would not give me a
reason. so i thought ill just restart because that usually happens when the
games doesnt close properly sometimes. when my pc was starting up the loading
windows screen came up and then a blue screen flashed really quickly. i could
not read what was on it. I was able to get in through safe mode and the last
thing i did was the file compression and i made a restore point right before
i did it and i uncompressed and it still didnt work so then i went back in
safe mode and restored to the point made right before i compressed and i set
it back and now it works again. the reason why this is i think, is because
its compresses your windows files including the ones that are required to
boot up the computer, so that is why i could not boot up. I dont know why i
was able to get into safe mode when this happened, and i'm not sure if the
compression was the actual reason why this happened but that was the last
thing that was changed on my computer before that started happening. If
anyone else has any ideas what might have actually caused this problem if i
am wrong about this please let us know. I would love to know what todo to
prevent this from happening in the future and be able to compress to save
drive space at least until i am able to clone my C-drive onto a bigger one
(possibly a SATA 160Gb) if anyone has any idea on how to get this to work
with out me having to install windows and everything else that was on the
drive let me know. thanks
tried to play a game that was on it it would not open and would not give me a
reason. so i thought ill just restart because that usually happens when the
games doesnt close properly sometimes. when my pc was starting up the loading
windows screen came up and then a blue screen flashed really quickly. i could
not read what was on it. I was able to get in through safe mode and the last
thing i did was the file compression and i made a restore point right before
i did it and i uncompressed and it still didnt work so then i went back in
safe mode and restored to the point made right before i compressed and i set
it back and now it works again. the reason why this is i think, is because
its compresses your windows files including the ones that are required to
boot up the computer, so that is why i could not boot up. I dont know why i
was able to get into safe mode when this happened, and i'm not sure if the
compression was the actual reason why this happened but that was the last
thing that was changed on my computer before that started happening. If
anyone else has any ideas what might have actually caused this problem if i
am wrong about this please let us know. I would love to know what todo to
prevent this from happening in the future and be able to compress to save
drive space at least until i am able to clone my C-drive onto a bigger one
(possibly a SATA 160Gb) if anyone has any idea on how to get this to work
with out me having to install windows and everything else that was on the
drive let me know. thanks