hard drive impact on overall system performance

  • Thread starter Thread starter steve.anon
  • Start date Start date
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steve.anon

Hi guys, I consider myself a decent computer tweaker, but recently
something I had learned to live with has bugged me - and I'd like to
fix it. Maybe you can help.

Let me explain: my current box is a p4 3Ghz, 1Gig of ddr2 ram, win xp.
The hard drive is 180gig SATA. It plays the latest video games, etc, no
problem. But, say I unrar a 600 meg file, that's when I can hear the
drive go in overdrive. Fair enough as it's probalby reading and writing
at the same time, but that doesn't explain why the machine slows down
to crawl when that happens.

What I don't understand is why it slows down at all. After all I'm
using only 200meg of ram, so there's no reason for swapping. Unraring a
file itself takes very little ram if any. No, it seems to be just
'using' a drive that somehow overload the bus and slows down the rest.

Now, the issue is common to all computer I ever owned or worked on
(including my good ol' 386). Basically, I build them with the fastest
components of the time, yet every single box had the hard drive as a
bottle neck to performance.

Is there a way to somehow 'fix' this issue? Or is this just the way
things work?

Any advice would be appreciated.

Steve.
 
Hi guys, I consider myself a decent computer tweaker, but recently
something I had learned to live with has bugged me - and I'd like to
fix it. Maybe you can help.

Let me explain: my current box is a p4 3Ghz, 1Gig of ddr2 ram, win xp.
The hard drive is 180gig SATA. It plays the latest video games, etc,
no problem. But, say I unrar a 600 meg file, that's when I can hear
the drive go in overdrive. Fair enough as it's probalby reading and
writing at the same time, but that doesn't explain why the machine
slows down to crawl when that happens.

What I don't understand is why it slows down at all. After all I'm
using only 200meg of ram, so there's no reason for swapping. Unraring
a file itself takes very little ram if any. No, it seems to be just 'using' a
drive that somehow overload the bus and slows down the rest.
Click to expand...

Have you got DMA enabled ? I dont get that result myself,
even when its an rar thats got heaps of very small files in it.
That last situation does take some time, but it doesnt slow
anything else down while its happening, and thats on the
rather low horsepower test machine, only 900MHz. I can
play a captured digital video file on that machine with no
visible effect on the video play.
Now, the issue is common to all computer I ever owned
or worked on (including my good ol' 386). Basically, I build
them with the fastest components of the time, yet every
single box had the hard drive as a bottle neck to performance.
Click to expand...

Thats normal, because hard drives are the main bottleneck
when doing something like unpacking an rar.
Is there a way to somehow 'fix' this issue?
Click to expand...

Maybe if you dont have DMA enabled.
 
What I don't understand is why it slows down at all. After all I'm
using only 200meg of ram, so there's no reason for swapping. Unraring a
file itself takes very little ram if any. No, it seems to be just
'using' a drive that somehow overload the bus and slows down the rest.
Click to expand...

I'm not sure either. I have 2.4GHz P4 and ATA 100 HD's and when I
unzip or unrar huge files into multiple small files, my PC doesn't
slow to a crawl and my CPU useage usually don't get more than 10%.

I'd say something isn't set right on your system if your system
crawls. See if your HD are set to UDMA rather than PIO (not sure if
that applies to SATA) and make sure you are using correct and up to
date driver. Generic driver could hinder performance. Also ehat type
of chipset and are you using onboard SATA or add on SATA card?
 
Disable antivirus software and try again.
What's avg. file size inside your rar file?
What average Split IO/Sec you get when you unrar?
 
Let me explain: my current box is a p4 3Ghz, 1Gig of ddr2 ram, win xp.
The hard drive is 180gig SATA. It plays the latest video games, etc,
no problem. But, say I unrar a 600 meg file, that's when I can hear
the drive go in overdrive. Fair enough as it's probalby reading and
writing at the same time, but that doesn't explain why the machine
slows down to crawl when that happens.
Click to expand...

If something else accesses the drive (i.e windows system, or swap),
then it has to wait longer.
What I don't understand is why it slows down at all. After all I'm
using only 200meg of ram, so there's no reason for swapping. Unraring
a file itself takes very little ram if any. No, it seems to be just
'using' a drive that somehow overload the bus and slows down the rest.
Click to expand...

Windows task scheduling isn't the best, open task manager and set
the priority of the task using most cpu to "BelowNormal"

If you have multiple disks, move your swap file to another disk,
and keep disk operations off the windows drive as much as possible.

Enabling hyperthreading on your P4 might help too.

If you have lots of ram, you can setup a ramdrive b: and use that
for temporary files...
 
Previously said:
Hi guys, I consider myself a decent computer tweaker, but recently
something I had learned to live with has bugged me - and I'd like to
fix it. Maybe you can help.
Click to expand...
Let me explain: my current box is a p4 3Ghz, 1Gig of ddr2 ram, win xp.
The hard drive is 180gig SATA. It plays the latest video games, etc, no
problem. But, say I unrar a 600 meg file, that's when I can hear the
drive go in overdrive. Fair enough as it's probalby reading and writing
at the same time, but that doesn't explain why the machine slows down
to crawl when that happens.
Click to expand...
What I don't understand is why it slows down at all. After all I'm
using only 200meg of ram, so there's no reason for swapping. Unraring a
file itself takes very little ram if any. No, it seems to be just
'using' a drive that somehow overload the bus and slows down the rest.
Click to expand...
Now, the issue is common to all computer I ever owned or worked on
(including my good ol' 386). Basically, I build them with the fastest
components of the time, yet every single box had the hard drive as a
bottle neck to performance.
Click to expand...
Is there a way to somehow 'fix' this issue? Or is this just the way
things work?
Click to expand...

It cannot really be fixed. The problem is that modern OSes di write
buffering. At some time the buffers age enough that a foced flush is
needed. This means the writing gets priotity over every other action,
hence the slowdown. One thing you can do on a decent OS is mount
the disk as "suncronous", causing the OS to not do write buffering.
This degrades performance but increases responsiveness for other tasks.

The problem is not so bad with better I/O sheduling. Also if you read
from one disk and write to anothyer you get significantly less head
movements in the disks, and these are still slow.

Arno
 
Hi there, thank you to everyone who replied! To answer all the
questions:
- the disk doesn't have vendor-specific drivers (seagate has an FAQ
about that, basically they say drivers don't exist as the xp ones are
good enough)
- the disk specs are:
Model Number:ST3160827AS (it's an NCQ model)
Capacity:160 GB
Speed:7200 rpm
Seek time:8.5 ms avg
Interface:SATA 1.5Gb/s
- my CPU usage never goes higher than 10%
- the antivirus is off
- hyper threading is on

I'm afraid Arno Wagner might be right, since as he said transferring
from one drive to another doesn't slow the system anywhere as much.
There may be nothing to do, or is it? Anything I could purchase (raid
array?)

Cheers,

Steve.
 
Previously said:
Hi there, thank you to everyone who replied! To answer all the
questions:
- the disk doesn't have vendor-specific drivers (seagate has an FAQ
about that, basically they say drivers don't exist as the xp ones are
good enough)
- the disk specs are:
Model Number:ST3160827AS (it's an NCQ model)
Capacity:160 GB
Speed:7200 rpm
Seek time:8.5 ms avg
Interface:SATA 1.5Gb/s
- my CPU usage never goes higher than 10%
- the antivirus is off
- hyper threading is on
Click to expand...
I'm afraid Arno Wagner might be right, since as he said transferring
from one drive to another doesn't slow the system anywhere as much.
There may be nothing to do, or is it? Anything I could purchase (raid
array?)
Click to expand...

RAID does not help for this specific problem. Raid can give you more
bandwidth, but not better access time (it can to some limited degree,
e.g. when you are only reading).

One thing that does help is using a storage device that has no
performance penalty for random access. The ones I can think of are
RAM-disks and flash-disks. Both extremely expensive.

Also buying a very fast 15.000 rpm disk with low seek time would
help somewhat, maybe making access twice as fast if you are lucky.
These disks are also pretty expensive.

Then your disk may be fragmented and defragging it would help.
I do not have much experience with that, since I mainly use Linux
and the filesystems there do not fragment to any significant degree.

BTW, the CPU can transfer data much faster than the disks can
read or write even in the fastest (linear) case. So the 10% CPU
do not mean anything.

Arno
 
Thank Arno - the disked is defragged regularly and I was just
mentionning the CPU usage during decompression of the rar file because
someone asked :)

I'm going to give the ram disk approach a shot. Gigabyte has those ram
drive that use conventional DDR ram, so it could be a reasonnably
priced option.

Cheers,

Steve.
 
Hi guys, I consider myself a decent computer tweaker, but recently
something I had learned to live with has bugged me - and I'd like to
fix it. Maybe you can help.

Let me explain: my current box is a p4 3Ghz, 1Gig of ddr2 ram, win xp.
The hard drive is 180gig SATA. It plays the latest video games, etc, no
problem. But, say I unrar a 600 meg file, that's when I can hear the
drive go in overdrive. Fair enough as it's probalby reading and writing
at the same time, but that doesn't explain why the machine slows down
to crawl when that happens.

What I don't understand is why it slows down at all. After all I'm
using only 200meg of ram, so there's no reason for swapping. Unraring a
file itself takes very little ram if any. No, it seems to be just
'using' a drive that somehow overload the bus and slows down the rest.

Now, the issue is common to all computer I ever owned or worked on
(including my good ol' 386). Basically, I build them with the fastest
components of the time, yet every single box had the hard drive as a
bottle neck to performance.

Is there a way to somehow 'fix' this issue? Or is this just the way
things work?

Any advice would be appreciated.

Steve.
Click to expand...

I recommend two different approaches, both of which I have implemented on
my own system.

Number 1, put your operating system and applications on a separate hard
drive from your data. Make sure this OS hard drive does not share an IDE
channel with the data drive.

Number 2, get yourself a dual cpu system. This is much easier with the new
single chip dual cpu processors.
 
HenryNettles said:
I recommend two different approaches, both of which I have
implemented on my own system.
Click to expand...
Number 1, put your operating system and applications on a separate
hard drive from your data. Make sure this OS hard drive does not
share an IDE channel with the data drive.
Click to expand...

Completely pointless. Modern OSs dont keep reloading bits of the app
while running the app. The most that does is minimise app start time.
Number 2, get yourself a dual cpu system. This is much
easier with the new single chip dual cpu processors.
Click to expand...

That assumes the apps can take advantage of that.
 
the rest.



It cannot really be fixed. The problem is that modern OSes di
write
buffering. At some time the buffers age enough that a foced
flush is
needed. This means the writing gets priotity over every other
action,
hence the slowdown. One thing you can do on a decent OS is
mount
the disk as "suncronous", causing the OS to not do write
buffering.
This degrades performance but increases responsiveness for
other tasks.

The problem is not so bad with better I/O sheduling. Also if
you read
from one disk and write to anothyer you get significantly less
head
movements in the disks, and these are still slow.

Arno
Click to expand...

hate to but in on the inside of your little conversation but the
slowest part of a computer will always be memory, not ram. HD memory,
it laggs the computer because when you are loading the data the
processor has to process it store it in ram and present it to you, or
lets say going from drive to crive you only have a certain transfer
rate, if you are so worried i would suggest either going with one
large 10,000 rpm SATA drive or something like dual 10,000 rpm raid
drives, which ov course would speed thing up.

raid works as a virtual data spliter, lets say you have 2 people doing
the same math problem at the same time, a single drive would do the
entire problem itself, while dual raid drives would seperate the
problem, each would do its own part and put it together, so if you
have a 2mb file half is on one drive and half is on the other, but the
computer sees the drive as one unit, but the read speed it 2 times
faster.
 
ROTFLOL. Who needs Mindspring.

truverman said:
hate to but in on the inside of your little conversation but the
slowest part of a computer will always be memory, not ram. HD memory,
it laggs the computer because when you are loading the data the
processor has to process it store it in ram and present it to you, or
lets say going from drive to crive you only have a certain transfer
rate, if you are so worried i would suggest either going with one
large 10,000 rpm SATA drive or something like dual 10,000 rpm raid
drives, which ov course would speed thing up.

raid works as a virtual data spliter, lets say you have 2 people doing
the same math problem at the same time, a single drive would do the
entire problem itself, while dual raid drives would seperate the
problem, each would do its own part and put it together, so if you
have a 2mb file half is on one drive and half is on the other, but the
computer sees the drive as one unit, but the read speed it 2 times
faster.
Click to expand...
 
hate to but in on the inside of your little conversation but the
slowest part of a computer will always be memory, not ram. HD memory,
it laggs the computer because when you are loading the data the
processor has to process it store it in ram and present it to you, or
lets say going from drive to crive you only have a certain transfer
rate, if you are so worried i would suggest either going with one
large 10,000 rpm SATA drive or something like dual 10,000 rpm raid
drives, which ov course would speed thing up.
Click to expand...

<ditto>

Hello,

In reality, "memory" and "RAM" are synonymous. The former is rarely, if
ever, used to describe the capacity (or free space) of hard disks.

RAM does stand for "Random Access Memory," after all. :-)


Cordially,
John Turco <[email protected]>
 
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