Microsoft Operating System Forum

Angus Rodgers

I've recently doubled my system RAM to 512MB, with no problems.

There's room on my motherboard (ASUS A7V8X-X) to plug in another
similar 256MB module. (I don't think I want to add 512MB merely
because it might be useful when/if I get around to dual-booting
some version of Linux. A total of 768MB ought to be enough. I
would rather not have to fiddle with MaxPhysPage=39999 - or what-
ever else would be needed if I had 1GB or more memory - unless
it is absolutely necessary, in which case I will think again.)

In system.ini at the moment, I have MaxFileCache=163840 (160MB),
and (presumably much less important) MinFileCache=8192 (8MB).

From what little I've read on the subject, I get the impression
that it will be OK to set MaxFileCache=327680 (320MB) (or indeed
any value up to 512MB) - the value of MinFileCache not really
being important at all - and then go ahead and install the extra
256MB.

I just have two questions:

(1) As I gather that system.ini is not processed when you boot
into Safe Mode, does this mean that Windows will reserve too
many memory addresses for VCache to be able to boot into Safe
Mode at all?

<http://support.microsoft.com/default.aspx?scid=KB;EN-US;q253912>

"The Windows 32-bit protected-mode cache driver (Vcache) determines
the maximum cache size based on the amount of RAM that is present
when Windows starts. Vcache then reserves enough memory addresses
to permit it to access a cache of the maximum size so that it can
increase the cache to that size if needed. These addresses are
allocated in a range of virtual addresses from 0xC0000000 through
0xFFFFFFFF (3 to 4 gigabytes) known as the system arena.

On computers with large amounts of RAM, the maximum cache size can
be large enough that Vcache consumes all of the addresses in the
system arena, leaving no virtual memory addresses available for
other functions such as opening an MS-DOS prompt (creating a new
virtual machine)."

(2) If I set MaxFileCache to some value less than 256MB (e.g.
leaving it at its present value of 160MB), will applications
running under Win98SE (in normal mode, I mean, not Safe Mode)
be able to use the more than 512MB of RAM that would seem to
be available even when the cache is filled up to the maximum?
(If not, might I as well set MinFileCache to 256MB or more?)

--
Angus Rodgers
(twirlip@ eats spam; reply to angusrod@)
Contains mild peril

MEB

NOTE:
If the system has 700MB's of RAM or more installed the following line MUST
be added to the [vcache] section of windows\system.ini file.

MaxFileCache=512000

For more info see:
Brian A. Sesko
"Re: too much memory?" - this discussion group
Sunday, May 11, 2008 05:21 AM
http://groups.google.fr/group/micros...d498782ed72def

and see:
someone watching
Sun, 11 May 2008 17:26:00 -0500
same discussion

--
MEB
http://peoplescounsel.orgfree.com
--
_________


"Angus Rodgers" <twirlip@bigfoot.com> wrote in message
news:rm9v541k9gap0aik0sbne4g0o6ef0kamjn@4ax.com...
| I've recently doubled my system RAM to 512MB, with no problems.
|
| There's room on my motherboard (ASUS A7V8X-X) to plug in another
| similar 256MB module. (I don't think I want to add 512MB merely
| because it might be useful when/if I get around to dual-booting
| some version of Linux. A total of 768MB ought to be enough. I
| would rather not have to fiddle with MaxPhysPage=39999 - or what-
| ever else would be needed if I had 1GB or more memory - unless
| it is absolutely necessary, in which case I will think again.)
|
| In system.ini at the moment, I have MaxFileCache=163840 (160MB),
| and (presumably much less important) MinFileCache=8192 (8MB).
|
| From what little I've read on the subject, I get the impression
| that it will be OK to set MaxFileCache=327680 (320MB) (or indeed
| any value up to 512MB) - the value of MinFileCache not really
| being important at all - and then go ahead and install the extra
| 256MB.
|
| I just have two questions:
|
| (1) As I gather that system.ini is not processed when you boot
| into Safe Mode, does this mean that Windows will reserve too
| many memory addresses for VCache to be able to boot into Safe
| Mode at all?
|
| <http://support.microsoft.com/default.aspx?scid=KB;EN-US;q253912>
|
| "The Windows 32-bit protected-mode cache driver (Vcache) determines
| the maximum cache size based on the amount of RAM that is present
| when Windows starts. Vcache then reserves enough memory addresses
| to permit it to access a cache of the maximum size so that it can
| increase the cache to that size if needed. These addresses are
| allocated in a range of virtual addresses from 0xC0000000 through
| 0xFFFFFFFF (3 to 4 gigabytes) known as the system arena.
|
| On computers with large amounts of RAM, the maximum cache size can
| be large enough that Vcache consumes all of the addresses in the
| system arena, leaving no virtual memory addresses available for
| other functions such as opening an MS-DOS prompt (creating a new
| virtual machine)."
|
| (2) If I set MaxFileCache to some value less than 256MB (e.g.
| leaving it at its present value of 160MB), will applications
| running under Win98SE (in normal mode, I mean, not Safe Mode)
| be able to use the more than 512MB of RAM that would seem to
| be available even when the cache is filled up to the maximum?
| (If not, might I as well set MinFileCache to 256MB or more?)
|
| --
| Angus Rodgers
| (twirlip@ eats spam; reply to angusrod@)
| Contains mild peril

Angus Rodgers

On Mon, 23 Jun 2008 14:30:35 -0400, "MEB"
<meb@not here@hotmail.com> wrote:

>NOTE:
>If the system has 700MB's of RAM or more installed the following line MUST
>be added to the [vcache] section of windows\system.ini file.
>
>MaxFileCache=512000
>
>For more info see:
>Brian A. Sesko
>"Re: too much memory?" - this discussion group
>Sunday, May 11, 2008 05:21 AM
>http://groups.google.fr/group/micros...d498782ed72def
>
>and see:
>someone watching
>Sun, 11 May 2008 17:26:00 -0500
>same discussion

With respect, I did do some homework before asking my questions.
I'm sorry if I didn't do enough, but it's not clear to me where
to look next. (I'm a reasonably experienced Win9x user, but by
no stretch of the imagination am I an expert.)

I had already read the thread you've referred me to, as well as
every other relevant thread I could find in the newsgroup since
11 Sep 2007. (Of course I can Google further back than that, if
it's really necessary.)

Do you mean /exactly/ 700MB? Do you mean that the MaxFileCache
value must be /exactly/ 512000 (not even an integral number of
megabytes!)? If so, why?

I was asking for information, not instructions without reasons
attached. Your instructions seem too precise and insufficiently
informative.

--
Angus Rodgers
(twirlip@ eats spam; reply to angusrod@)
Contains mild peril

Ron Martell

Angus Rodgers <twirlip@bigfoot.com> wrote:

<snip>
>In system.ini at the moment, I have MaxFileCache=163840 (160MB),
>and (presumably much less important) MinFileCache=8192 (8MB).
>


I think you are unnecessarily limiting the overall performance of your
computer by placing such a low limitation on the amount of memory used
for caching files. The result is additional hard drive access as
needed files are repeatedly reloaded from the hard drive, which takes
at least 1,000 times as long as it would if they were retained (=
cached) after being loaded.

If this were my computer I would increase the MaxFileCache value to
512000 so as to obtain the most effective use of the available RAM.
RAM used for disk cache is always considered to be a lower priority
use than RAM used for actual program execution or data file processing
so if additional RAM is needed for these items the system will
automatically reduce the disk cache size to less than the specified
maximum so as to provide the needed RAM.

Hope this is of some assistance.

Good luck

Ron Martell Duncan B.C. Canada
--
Microsoft MVP (1997 - 2008)
On-Line Help Computer Service
http://onlinehelp.bc.ca

"Anyone who thinks that they are too small to make a difference
has never been in bed with a mosquito."

Angus Rodgers

On Mon, 23 Jun 2008 20:08:24 +0100, I hastily wrote:

>[...] Do you mean that the MaxFileCache
>value must be /exactly/ 512000 (not even an integral number of
>megabytes!)?

<blush>

Actually, it's exactly 500MB! But again, why this exact value
(which is a round-looking number in the decimal system but not
in the binary system)?

--
Angus Rodgers
(twirlip@ eats spam; reply to angusrod@)
Contains mild peril

glee

"Angus Rodgers" <twirlip@bigfoot.com> wrote in message
news:rm9v541k9gap0aik0sbne4g0o6ef0kamjn@4ax.com...
> I've recently doubled my system RAM to 512MB, with no problems.
>
> There's room on my motherboard (ASUS A7V8X-X) to plug in another
> similar 256MB module. (I don't think I want to add 512MB merely
> because it might be useful when/if I get around to dual-booting
> some version of Linux. A total of 768MB ought to be enough. I
> would rather not have to fiddle with MaxPhysPage=39999 - or what-
> ever else would be needed if I had 1GB or more memory - unless
> it is absolutely necessary, in which case I will think again.)
>
> In system.ini at the moment, I have MaxFileCache=163840 (160MB),
> and (presumably much less important) MinFileCache=8192 (8MB).
>
> From what little I've read on the subject, I get the impression
> that it will be OK to set MaxFileCache=327680 (320MB) (or indeed
> any value up to 512MB) - the value of MinFileCache not really
> being important at all - and then go ahead and install the extra
> 256MB.
>
> I just have two questions:
>
> (1) As I gather that system.ini is not processed when you boot
> into Safe Mode, does this mean that Windows will reserve too
> many memory addresses for VCache to be able to boot into Safe
> Mode at all?
>
> <http://support.microsoft.com/default.aspx?scid=KB;EN-US;q253912>
>
> "The Windows 32-bit protected-mode cache driver (Vcache) determines
> the maximum cache size based on the amount of RAM that is present
> when Windows starts. Vcache then reserves enough memory addresses
> to permit it to access a cache of the maximum size so that it can
> increase the cache to that size if needed. These addresses are
> allocated in a range of virtual addresses from 0xC0000000 through
> 0xFFFFFFFF (3 to 4 gigabytes) known as the system arena.
>
> On computers with large amounts of RAM, the maximum cache size can
> be large enough that Vcache consumes all of the addresses in the
> system arena, leaving no virtual memory addresses available for
> other functions such as opening an MS-DOS prompt (creating a new
> virtual machine)."
>
> (2) If I set MaxFileCache to some value less than 256MB (e.g.
> leaving it at its present value of 160MB), will applications
> running under Win98SE (in normal mode, I mean, not Safe Mode)
> be able to use the more than 512MB of RAM that would seem to
> be available even when the cache is filled up to the maximum?
> (If not, might I as well set MinFileCache to 256MB or more?)

A agree with Ron Martell's reply wholeheartedly. Set the MaxFileCache to 512000 for
best performance with that amount of RAM installed.

Additionally, there is no need to have any MinFileCache entry in your case. I would
remove the entire MinFileCache line from the .system.ini file.
--
Glen Ventura, MS MVP Windows, A+
http://dts-l.net/
http://dts-l.net/goodpost.htm

Angus Rodgers

On Mon, 23 Jun 2008 12:10:02 -0700, Ron Martell
<ron.martell@gmail.com> wrote:

>Angus Rodgers <twirlip@bigfoot.com> wrote:
>
><snip>
>>In system.ini at the moment, I have MaxFileCache=163840 (160MB),
>>and (presumably much less important) MinFileCache=8192 (8MB).
>>
>
>
>I think you are unnecessarily limiting the overall performance of your
>computer by placing such a low limitation on the amount of memory used
>for caching files. The result is additional hard drive access as
>needed files are repeatedly reloaded from the hard drive, which takes
>at least 1,000 times as long as it would if they were retained (=
>cached) after being loaded.
>
>If this were my computer I would increase the MaxFileCache value to
>512000 so as to obtain the most effective use of the available RAM.
>RAM used for disk cache is always considered to be a lower priority
>use than RAM used for actual program execution or data file processing
>so if additional RAM is needed for these items the system will
>automatically reduce the disk cache size to less than the specified
>maximum so as to provide the needed RAM.
>
>Hope this is of some assistance.

What worries me about using a larger MaxFileCache value is that Windows
not only keeps a large swapfile, but System Monitor starts to show quite
a large value for "Swapfile in use". (I forget the exact figures, but I
did a few informal experiments.) On the face of it, it seems irrational
to have a large quantity of disk data cached in RAM at the same time as
a large quantity of RAM data is being paged out to disk! But I don't
have a clear enough mental model of how Win98SE handles things to draw
any firm conclusion from such a vague argument; it just makes me uneasy.

As a result of this uneasiness, I have been keeping the MaxFileCache
value low enough that "Swapfile in use" shows as zero except when I'm
really stressing the system. But I'm not convinced that this is a good
policy, and I'm quite willing to change it (so long as I understand what
I'm doing, better than I do at the moment!).

--
Angus Rodgers
(twirlip@ eats spam; reply to angusrod@)
Contains mild peril

glee

"Angus Rodgers" <twirlip@bigfoot.com> wrote in message
news:9utv54pu4nh0j0m2q10kc1ha2naqqil1s4@4ax.com...
> On Mon, 23 Jun 2008 12:10:02 -0700, Ron Martell
> <ron.martell@gmail.com> wrote:
>
>>Angus Rodgers <twirlip@bigfoot.com> wrote:
>>
>><snip>
>>>In system.ini at the moment, I have MaxFileCache=163840 (160MB),
>>>and (presumably much less important) MinFileCache=8192 (8MB).
>>>
>>
>>
>>I think you are unnecessarily limiting the overall performance of your
>>computer by placing such a low limitation on the amount of memory used
>>for caching files. The result is additional hard drive access as
>>needed files are repeatedly reloaded from the hard drive, which takes
>>at least 1,000 times as long as it would if they were retained (=
>>cached) after being loaded.
>>
>>If this were my computer I would increase the MaxFileCache value to
>>512000 so as to obtain the most effective use of the available RAM.
>>RAM used for disk cache is always considered to be a lower priority
>>use than RAM used for actual program execution or data file processing
>>so if additional RAM is needed for these items the system will
>>automatically reduce the disk cache size to less than the specified
>>maximum so as to provide the needed RAM.
>>
>>Hope this is of some assistance.
>
> What worries me about using a larger MaxFileCache value is that Windows
> not only keeps a large swapfile, but System Monitor starts to show quite
> a large value for "Swapfile in use". (I forget the exact figures, but I
> did a few informal experiments.) On the face of it, it seems irrational
> to have a large quantity of disk data cached in RAM at the same time as
> a large quantity of RAM data is being paged out to disk! But I don't
> have a clear enough mental model of how Win98SE handles things to draw
> any firm conclusion from such a vague argument; it just makes me uneasy.
>
> As a result of this uneasiness, I have been keeping the MaxFileCache
> value low enough that "Swapfile in use" shows as zero except when I'm
> really stressing the system. But I'm not convinced that this is a good
> policy, and I'm quite willing to change it (so long as I understand what
> I'm doing, better than I do at the moment!).

I suggest you carefully read here for a better understanding:

Memory Management in Win98 & ME
http://aumha.org/win4/a/memmgmt.htm

--
Glen Ventura, MS MVP Windows, A+
http://dts-l.net/
http://dts-l.net/goodpost.htm

Angus Rodgers

On Mon, 23 Jun 2008 16:04:56 -0400, "glee"
<glee29@spamindspring.com> wrote:

>"Angus Rodgers" <twirlip@bigfoot.com> wrote in message
>news:9utv54pu4nh0j0m2q10kc1ha2naqqil1s4@4ax.com.. .
>
>> What worries me about using a larger MaxFileCache value is that Windows
>> not only keeps a large swapfile, but System Monitor starts to show quite
>> a large value for "Swapfile in use". (I forget the exact figures, but I
>> did a few informal experiments.) On the face of it, it seems irrational
>> to have a large quantity of disk data cached in RAM at the same time as
>> a large quantity of RAM data is being paged out to disk! But I don't
>> have a clear enough mental model of how Win98SE handles things to draw
>> any firm conclusion from such a vague argument; it just makes me uneasy.
>>
>> As a result of this uneasiness, I have been keeping the MaxFileCache
>> value low enough that "Swapfile in use" shows as zero except when I'm
>> really stressing the system. But I'm not convinced that this is a good
>> policy, and I'm quite willing to change it (so long as I understand what
>> I'm doing, better than I do at the moment!).
>
>I suggest you carefully read here for a better understanding:
>
>Memory Management in Win98 & ME
>http://aumha.org/win4/a/memmgmt.htm

I thought I had read it already, but I had missed this paragraph:

"If code or data were stored in VCache only for caching purposes,
then it should be emptied out before the swap file is used; but in
Win98/ME, VCache often will stay quite large, forcing the swap file
to be used more. Is this another memory leak? No, it isn’t. It would
be a memory leak if the contents of VCache were only stored, inactive
code or data. But if the contents are code or data currently being used
(as it commonly will be in Win98/ME), we have quite another story!"

That reassures me somewhat. I'll mull it over, and consider increasing
MaxFileCache (and deleting MinFileCache altogether).

Assuming this is OK, it makes my second question (in the OP) pretty
much irrelevant (but still of some academic interest). However, my
main worry was the first question - the one about Safe Mode - which
has still not been answered.

--
Angus Rodgers
(twirlip@ eats spam; reply to angusrod@)
Contains mild peril

MEB

The number comes from both users and Microsoft via their testing. Seems the
system sweet spot or what it can readily handled in the *most* number of
motherboards/BIOS/chipsets and with a *normal* load of applications, devices
and other, vying for addressing/resource use.. experimentation is always in
order.

Here's another setting that ALWAYS brought wrath from the MVPs when I used
to present it here:
system.ini
[386Enh]
ConservativeSwapfileUsage=1

Above works for some, others complain...


As for your Safe Mode question: if your Normal Start can handle the memory,
Safe Mode has no difficulty [at least in all the testing I have done]. Safe
Mode isn't {by default} going to run any of the devices/drivers that might
take up or conflict with addressing. Everything is limited, in compatibility
mode, or disabled.

Here's some personal test results for sweet spot memory:
Super Socket 7 = 128 - *256 megs
Slot 1 and Socket 370 = *384 megs
Newer depends more on motherboard, chipset, and memory manufacturer {FSB,
RAS/CAS, which VIA or Intel set, etc} from 384 to 768 megs.
Results obtained when tested with Office and various games using several
different video cards and processors {over-clocked and not}.

--
MEB
http://peoplescounsel.orgfree.com
--
_________

"Angus Rodgers" <twirlip@bigfoot.com> wrote in message
news:c8tv541v7lbjba7vcldv5il3o7h1553p6u@4ax.com...
| On Mon, 23 Jun 2008 20:08:24 +0100, I hastily wrote:
|
| >[...] Do you mean that the MaxFileCache
| >value must be /exactly/ 512000 (not even an integral number of
| >megabytes!)?
|
| <blush>
|
| Actually, it's exactly 500MB! But again, why this exact value
| (which is a round-looking number in the decimal system but not
| in the binary system)?
|
| --
| Angus Rodgers
| (twirlip@ eats spam; reply to angusrod@)
| Contains mild peril