Mem
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2
Mem
Displays information about allocated memory areas, free memory areas, and programs that are currently loaded into memory in the MS-DOS subsystem. Used without parameters, mem displays the status of the MS-DOS subsystem's used and free memory.
Important
Windows XP and the Windows Server 2003 family of products do not use this command. It is included only to preserve compatibility with existing MS-DOS files, but it has no effect at the command line because the functionality is automatic.
This tool is not available on the Itanium-based versions of the Windows operating systems.
This tool is not available on the x64-based versions of the Windows operating systems.
Syntax
mem [{/program | /debug | /classify}]
Parameters
- /program
Displays the status of programs that are currently loaded into memory.
- /debug
Displays the status of currently loaded programs and internal drivers, and other programming information.
- /classify
Displays the status of programs loaded into conventional memory and the upper memory area (UMA).
- /?
Displays help at the command prompt.
Remarks
Using /program
You cannot use /program with /debug or /classify. You can abbreviate /program to /p.
Using /debug
You cannot use /debug with /program or /classify. You can abbreviate /debug to /d.
Using /classify
/classify lists the size of each program in decimal and hexadecimal notation, provides a summary of memory use, and lists the largest memory blocks that are available. You cannot use /classify with /program or /debug. You can abbreviate /classify to /c.
Displaying memory status
The MS-DOS subsystem displays the status of extended memory only if you have allocated memory above 1 MB.
Examples
Suppose your MS-DOS subsystem is configured with expanded memory. To display the status of your system's total memory (that is, conventional, expanded, extended) and a list of programs currently loaded into memory, type:
mem /program
The results might look similar to the following:
Address Name Size Type
000000 000400 Interrupt Vector
000400 000100 ROM Communication Area
000500 000200 DOS Communication Area
000700 IO 000310 System Data
000A10 MSDOS 0014D0 System Data
001EE0 IO 0018D0 System Data
KBD 000800 System Program
HIMEM 000420 DEVICE=
000340 FILES=
000090 FCBS=
000170 LASTDRIVE=
000710 STACKS=
0037C0 COMMAND 000A40 Program
004210 MSDOS 000070 - Free -
004290 COMMAND 0001F0 Environment
004490 MEM 0001D0 Environment
004670 MEM 017550 Program
01BBD0 MSDOS 084410 - Free -
09FFF0 SYSTEM 028000 System Program
0C8000 IO 0083D0 System Data
MOUSE 0083C0 System Program
0D03E0 MSDOS 000050 - Free -
0D0440 REDIR 0009F0 Program
0D0E40 DOSX 007CA0 Program
0D8AF0 DOSX 001030 Data
0D9B30 MSDOS 0164C0 - Free -
655360 bytes total conventional memory
655360 bytes available to MS-DOS
637296 largest executable program size
1048576 bytes total contiguous extended memory
0 bytes available contiguous extended memory
405504 bytes available XMS memory
MS-DOS resident in High Memory Area
"Total conventional memory" is the amount of virtual memory allocated to the MS-DOS subsystem up to the first 640KB.
"Available to MS-DOS" is the amount of conventional memory allocated, including the memory needed for Cmd.exe.
"Largest executable program size" is the largest contiguous block of conventional memory available for a program.
"Total EMS memory" (not shown in the preceding example) is the amount of expanded memory configured for the MS-DOS subsystem.
"Free EMS memory" (not shown in the preceding example) is the amount of expanded memory available for programs.
"Total contiguous extended memory" is the amount of memory beyond 1 MB.
"Available contiguous extended memory" is the extended memory available for the Interrupt 15h interface. This memory is not being managed by an extended memory manager, such as Himem.sys. Some older programs use this different extended memory scheme.
"Available XMS memory" is memory that is being managed by an extended-memory manager, such as Himem.sys, and that is available to programs that can use it.
Formatting legend
| Format | Meaning |
|---|---|
Italic |
Information that the user must supply |
Bold |
Elements that the user must type exactly as shown |
Ellipsis (...) |
Parameter that can be repeated several times in a command line |
Between brackets ([]) |
Optional items |
Between braces ({}); choices separated by pipe (|). Example: {even|odd} |
Set of choices from which the user must choose only one |
|
Code or program output |