Virtual Memory

[Dan]

Have a total of 3 hard drives. Was told I could speed up the performance of
my computer by doing the following.
Would like to completely remove virtual memory from one drive.
Would like to then divide my virtual memory between two different drives.
Can someone please give me instructions on how to do that. Also, will
doing this harm my computer in any way and will it actually increase
performance?

 

[Gerry Cornell]

Dan

http://aumha.org/a/parts.htm

--

~~~~~~


Hope this helps.

Gerry
~~~~~~~~~~~~~~~~~~~~~~~~
FCA

Stourport, Worcs, England
Enquire, plan and execute.
~~~~~~~~~~~~~~~~~~~~~~~~
Please tell the newsgroup how any
suggested solution worked for you.



~~~~~~~~~~~~~~~~~~~~~~~~

 

[Martin]

Have a total of 3 hard drives. Was told I could speed up the performance
of my computer by doing the following.
Would like to completely remove virtual memory from one drive.
Would like to then divide my virtual memory between two different drives.
Can someone please give me instructions on how to do that. Also, will
doing this harm my computer in any way and will it actually increase
performance?

It's an accepted theory that having your page file(s) on separate physical
drives from your operating system can improve performance.

I have a 160GB and a 40GB hard drive and have a 1GB page file on each of
them - Windows XP is on the 160GB drive too.
Can't say i notice much difference to having just a single page file on the
operating system's drive but maybe my pc runs a bit smoother with the two
page files.

To set your virtual memory open the System applet in the Control Panel.
Select the Advanced tab > Performance Settings.
This gets you to the Performance Options dialog.
Select the Advanced tab > Virtual Memory > Change.

Here's the settings that you need.
You should see all your hard drives listed and also see what you present
page file settings are.

Select a drive.
You can either set No Paging File, let Windows manage a page file on the
drive or set a Custom sized page file.
A custom sized page file with equal Initial and Maximum sizes is popular -
you can then eliminate fragmentation of the page file.
If you choose a custom size then you need to be sure that the maximum
(total) page file size is adequate for your pc and how you use it.

You'll probably need to reboot to effect any changes to your virtual memory
settings.

Martin.

 

[Ken Blake]

In

Have a total of 3 hard drives. Was told I could speed up the
performance of my computer by doing the following.

Assuming that these are physical drives, not just separate
partitions on a single drive, maybe. See below. If they are just
separate partitions, it will much more likely *hurt* performance.

Would like to completely remove virtual memory from one drive.

Don't do that. Keep at least a small amount on C:. If you don't,
some programs may complain.

Would like to then divide my virtual memory between two
different
drives. Can someone please give me instructions on how to do
that.

No need to divide it that way. Just move the rest to the
least-used of the other drives.

Read here: http://aumha.org/win5/a/xpvm.htm

Also, will doing this harm my computer in any way

No, not at all.

and will it
actually increase performance?

As I said, maybe. In theory it will (because it will save head
movement to and from the page file), but whether it make an
appreciable difference depends on how much you use the page file.
That in turn depends on how much RAM you have. If the amount of
RAM is in the lower ranges, you'll use the page file
significantly, and doing this can help. But if you have plenty of
RAM, you'll seldom use the page file, and you'll probably never
see a difference.

Again, don't make the mistake of moving the page file to a second
*partition* on your only physical drive. That will *increase*
head movement to and from it, and hurt performance.

 

[SFB - KB3MM]

Why do you want to do that?
Do you have a large page swap rate ?

 

[Gerry Cornell]

Martin

Read / write speeds for drives vary so what you say is not necessarily
true.


~~~~~~


Hope this helps.

Gerry
~~~~~~~~~~~~~~~~~~~~~~~~
FCA

Stourport, Worcs, England
Enquire, plan and execute.
~~~~~~~~~~~~~~~~~~~~~~~~
Please tell the newsgroup how any
suggested solution worked for you.



~~~~~~~~~~~~~~~~~~~~~~~~

 

[Martin]

Good point.

Another tip for the tweaking fanatic is to ensure that the pagefile is at
the start of the drive which it is located on.
(With a fixed size presumably).

The theory is that for a single disc revolution, the start of the drive
travels further than the end of the drive.
(The start of the drive is the outermost part of the disc).
More distance covered per unit of time equals higher speed.
So the nearer a pagefile is to the start of the drive, the faster it'll be
to read/write.

Martin.

 

[Venger]

Have a total of 3 hard drives. Was told I could speed up the performance
of my computer by doing the following.
Would like to completely remove virtual memory from one drive.
Would like to then divide my virtual memory between two different drives.
Can someone please give me instructions on how to do that. Also, will
doing this harm my computer in any way and will it actually increase
performance?

Alot of variables here, but the idea behind swap file optimization is the
following:

1) Remove contention between swap file access and other access

2) Place the swap file in the fast part of the fastest drive for fastest
access

Understanding these considerations, there are caveats - putting your swap
file on a 6.4GB drive is likely MUCH SLOWER than leaving it on the C:
partition of your 80GB drive.

Also, keep in mind that with three drives, at least one of them is most
likely a slave, and will contend with the master drive on that IDE
controller channel.

Can you describe your three hard drives capacity? How are they connected?
That will help steer you in the right direction...

Venger

 

[R. McCarty]

For Raxco Perfect Disk users, you'll notice that after an Off line
defrag the Pagefile will be placed almost "Dead-Center" on a
partition/drive.

I also believe that access time is a big factor in overall drive
performance. That's why even now, I still run Ultra-160 SCSI
drives. I do have a Tray IDE unit and just before posting I used
DiskSpeed to compare a Ultra-DMA5 verses SCSI. The IDE
drive averages around 20.0 mS compared with 8.5 mS for the
SCSI drives. The one thing I've not researched is SATA, If
any one has some specs on Access Times on a Serial ATA I'd
appreciate seeing some results.


this is a myth, first, being that the pagefile is the file that needs
the best spot on the disc, and second, that the best spot on the disc
are the first few cylendars.

neither is true

first, on a modern system, other files have more urgency then the
pagefile, but more important;

on the current hard drives, seek time actually turns out to be worse
not better on the first and last few percent of the drive's
cylinders..one reason is that the best place for seek time is where the
heads will be the majority of the time.

as far as performance, seek time absolutely dominates transfer time

but another reason, modern drive software now can the arm down in the
outer edges of the disc so it doeson't hit the limit
stops...obviously,hitting those is a VERY bad.

Seagate used to ship a hard drive called the "WrenRunner".

more expensive, with 10% less capacity over their other hardrive.

get this...it had average access times 20% better then their other
model, and so they charged more for the hardrive!...20%!!

HA!!! all Seagate did was lock out the first and last 5% cylinders!!!!

Now with the stop blocks safely far away from the cylinders that would
actually be used they can get full seek speeds across the entire
drive!...obviously, reducing the maximum stroke distance contributed as
another benefit.

you could tell clients to buy the cheaper/larger/"slower" drive, and
just not use all of it

in any event, because of stops, and the fact that the best place is
where the heads will be the majority of time, the beginning of a
hardrive is NOT the best spot on a disc other then boot files
[/QUOTE]

 

[Martin]

this is a myth, first, being that the pagefile is the file that needs
the best spot on the disc, and second, that the best spot on the disc
are the first few cylendars.

neither is true

first, on a modern system, other files have more urgency then the
pagefile, but more important;

on the current hard drives, seek time actually turns out to be worse
not better on the first and last few percent of the drive's
cylinders..one reason is that the best place for seek time is where the
heads will be the majority of the time.

as far as performance, seek time absolutely dominates transfer time

but another reason, modern drive software now can the arm down in the
outer edges of the disc so it doeson't hit the limit
stops...obviously,hitting those is a VERY bad.

Seagate used to ship a hard drive called the "WrenRunner".

more expensive, with 10% less capacity over their other hardrive.

get this...it had average access times 20% better then their other
model, and so they charged more for the hardrive!...20%!!

HA!!! all Seagate did was lock out the first and last 5% cylinders!!!!

Now with the stop blocks safely far away from the cylinders that would
actually be used they can get full seek speeds across the entire
drive!...obviously, reducing the maximum stroke distance contributed as
another benefit.

you could tell clients to buy the cheaper/larger/"slower" drive, and
just not use all of it

in any event, because of stops, and the fact that the best place is
where the heads will be the majority of time, the beginning of a
hardrive is NOT the best spot on a disc other then boot files
[/QUOTE]

Another tweak bites the dust!

Martin.

 

[Gerry Cornell]

Martin

Performance is not the only reason why users have partitioned drives.
Separating files that constantly fragment from those that do not will
bring benefits. It can makes backing up and housekeeping much simpler.

--

~~~~~~


Hope this helps.

Gerry
~~~~~~~~~~~~~~~~~~~~~~~~
FCA

Stourport, Worcs, England
Enquire, plan and execute.
~~~~~~~~~~~~~~~~~~~~~~~~
Please tell the newsgroup how any
suggested solution worked for you.



~~~~~~~~~~~~~~~~~~~~~~~~

this is a myth, first, being that the pagefile is the file that needs
the best spot on the disc, and second, that the best spot on the disc
are the first few cylendars.

neither is true

first, on a modern system, other files have more urgency then the
pagefile, but more important;

on the current hard drives, seek time actually turns out to be worse
not better on the first and last few percent of the drive's
cylinders..one reason is that the best place for seek time is where
the
heads will be the majority of the time.

as far as performance, seek time absolutely dominates transfer time

but another reason, modern drive software now can the arm down in the
outer edges of the disc so it doeson't hit the limit
stops...obviously,hitting those is a VERY bad.

Seagate used to ship a hard drive called the "WrenRunner".

more expensive, with 10% less capacity over their other hardrive.

get this...it had average access times 20% better then their other
model, and so they charged more for the hardrive!...20%!!

HA!!! all Seagate did was lock out the first and last 5%
cylinders!!!!

Now with the stop blocks safely far away from the cylinders that
would
actually be used they can get full seek speeds across the entire
drive!...obviously, reducing the maximum stroke distance contributed
as
another benefit.

you could tell clients to buy the cheaper/larger/"slower" drive, and
just not use all of it

in any event, because of stops, and the fact that the best place is
where the heads will be the majority of time, the beginning of a
hardrive is NOT the best spot on a disc other then boot files

Another tweak bites the dust!

Martin.
[/QUOTE]

 

[Alex Nichol]

Have a total of 3 hard drives. Was told I could speed up the performance of
my computer by doing the following.
Would like to completely remove virtual memory from one drive.
Would like to then divide my virtual memory between two different drives.

You have I think a confused idea, so do a bit of reading first. There
is no advantage in XP in spreading the page file over multiple drives -
paged out items do not get 'optimised' to some drive not likely to be in
use. Best is to put it on the HD that is likely to get least use, but
leave a notional file on C: (it will not come into existence but the
possibility is needed for emergencies)

Not that the traffic on a modern size RAM is going to be significant,
so the point is really rather academic. See
www.aumha.org/win5/a/xpvm.htm

 

[Alex Nichol]

http://aumha.org/a/parts.htm

That is on partitioning, and is not relevant to VM