IBM 09N4076 manual Enhancing performance in DOS and Windows, Memory

/S

This

parameter

instructs

MSCDEX.EXE

to

allow

networked

computers

to

share

CD-ROM

drives.

Conserving

DOS

conventional

memory

If

the

CD-ROM

drive-support

software

is

loaded

in

DOS

conventional

memory

(below

640

KB

RAM),

there

might

be

insufficient

memory

to

run

some

DOS

applications.

The

CDSETUP

program

attempts

to

load

the

IDE

CD-ROM drive device

driver

and

MSCDEX

into

upper

memory,

when

possible,

to

avoid

this

problem.

For

more information

on

techniques

to

conserve

conventional

memory,

refer

to

the

following

topics

in

the

documentation

that

comes

with your

operating

system:

ŸDOS=UMB, DOS=HIGH,UMB (CONFIG.SYS entry)

This

command

enables

the

use

of

upper

memory

and

loads

DOS,

MSCDEX,

and

the

IDE

CD-ROM

device

driver

in

upper

memory.

ŸHIMEM.SYS (CONFIG.SYS entry)

This	is a	device driver	that	manages	extended memory (RAM memory above 1
MB).	Windows	automatically	loads	this	device driver.

ŸEMM386.EXE (CONFIG.SYS entry)

This

is

a

device

driver that

allows

the

extended

memory

made available

by

HIMEM.SYS

to

be

used

as

expanded

memory.

The

MSCDEX /E

parameter

might

be

used

in

conjunction

with this

device

driver

to

move

the

cache

allocated

by

MSCDEX

into

this

memory,

thus

freeing

some

conventional

memory.

Ÿ

MEM

/C

/P

(use

from

DOS

prompt)

This

is

a

useful

DOS

utility

that

will

display

the

current

memory

allocation in

your

computer

to help you

understand

where

device

drivers

and

programs

are

located.

To

display

the

MEM

parameters

available,

at

the

DOS

prompt

type

mem/?

Enhancing performance in DOS and Windows

The following two procedures can enhance CD-ROM drive performance.

1. Allocate more MSCDEX cache (see /M parameter for MSCDEX).

2. Allow SMARTDRV to cache CD-ROM accesses.

The

CDSETUP

program

disables

the cache CD-ROM

data

function. Multisession

CDs

are

not

compatible

with

the

SMARTDRV

caching

method.

If

you do

not

plan

to

use

PhotoCD or

multiple-session CDs,

you

can

enable

caching

by

removing

the

/U

parameter

from

the

SMARTDRV

line

in

your

AUTOEXEC.BAT

or

CONFIG.SYS

file. This might improve the performance of

some

CD-ROM

applications.

You

must

have

SMARTDRV

5.0

or

later

to

cache

CD-ROM

data.

Part 2: Appendixes 2-17