Document revision date: 15 July 2002

How to Perform This Task

1. Use the RENAME command to rename the file to be deleted.
2. Shut down and reboot the system.
3. Delete the file.
4. When you delete a file, make sure you remove from SYPAGSWPFILES.COM and MODPARAMS.DAT any command lines related to the file.

Example

$ RENAME DUA2:[SYSTEM]PAGEFILE_1.SYS; DUA2:[SYSTEM]JUNK.SYS; $ @SYS$SYSTEM:SHUTDOWN.COM . . . [SHUTDOWN.COM shuts down and reboots the system] [When the system reboots, log in] . . . $ DELETE DUA2:[SYSTEM]JUNK.SYS;

16.16 Creating and Modifying Page, Swap, and Dump Files

For performance or disk space reasons, you might want to create system page, swap, and dump files on disks other than the system disk. (Error log dump files, however, must remain on the system disk.)

The following sections explain how to perform this task:

Method	For More Information
Using AUTOGEN (recommended method)	Section 16.16.1
Using SWAPFILES.COM (for primary files only)	Section 16.16.2
Using SYSGEN	Section 16.16.3

16.16.1 Using AUTOGEN (Recommended Method)

You can direct AUTOGEN to create new system page, swap, and dump files by adding symbols to MODPARAMS.DAT to specify the name, location, and size of new files to be created and then running AUTOGEN. Before performing this task, you should understand AUTOGEN and its parameter file MODPARAMS.DAT. For more information about when to use AUTOGEN, see Section 15.4. See Section 15.4.4 for information about MODPARAMS.DAT.

AUTOGEN automatically calculates appropriate sizes for system page, swap, and dump files. It also modifies the files to the appropriate sizes and installs them. You can control sizes calculated by AUTOGEN by defining symbols in the file MODPARAMS.DAT. For more information, see Section 16.16.1.2.

How to Perform This Task

To change the sizes of system page, swap, and dump files, execute AUTOGEN in two passes as follows:

1. Enter the following command to invoke a first pass of AUTOGEN. AUTOGEN displays its calculations for system file sizes to SYS$OUTPUT:

   $ @SYS$UPDATE:AUTOGEN SAVPARAMS TESTFILES

2. If the file sizes displayed in step 1 are inadequate, add symbols to MODPARAMS.DAT to control the size of files as explained in Section 16.16.1.2 and return to step 1.
3. When you are satisfied with the file sizes displayed in step 1, execute a second pass of AUTOGEN using the following command to install the modified system files when the system is rebooted:

   $ @SYS$UPDATE:AUTOGEN GENPARAMS REBOOT

4. Add commands to the site-specific startup command procedure SYPAGSWPFILES.COM to make sure the files are installed each time the system boots. For instructions, see Section 16.14.

Add the following symbols to MODPARAMS.DAT to specify the names and locations of the page and swap files to be created:

Definition	For Page Files	For Swap Files	For Dump Files
File name and location	PAGEFILE n_NAME = "file-spec"	SWAPFILE n_NAME = "file-spec"	DUMPFILE_DEVICE = "device"

where:

• n specifies the page or swap file. Refer to the primary page and swap files by specifying a value of 1 for n; refer to subsequent files by specifying increasingly higher integer values for n. For example, to refer to a secondary page or swap file, specify a value of 2 for n.
• file-spec specifies the full file specification of the file to be created, and should be within quotation marks ("").
• device specifies the disk name to be used, and should be within quotation marks ("").

You can add information to the AUTOGEN parameter file MODPARAMS.DAT to control the sizes that AUTOGEN calculates for system page, swap, and dump files. If you do not supply system file size information in MODPARAMS.DAT, AUTOGEN performs default size calculations for page, swap, and dump files.

You can define symbols in MODPARAMS.DAT to specify either of the following items:

Size to Be Specified	For More Information
Total desired size for all page or swap files on a system (not valid for the system dump files)	Table 16-4
Sizes for individual page, swap, or dump files	Table 16-5

For page and swap files, AUTOGEN generally manipulates the primary files SYS$SYSTEM:PAGEFILE.SYS and SYS$SYSTEM:SWAPFILE.SYS only if you have no other page and swap files. If you have secondary files, AUTOGEN manipulates the secondary files and excludes primary files. However, in some instances, AUTOGEN might modify the size of the primary page and swap files.

On VAX systems, for system dump files, AUTOGEN manipulates the size of only one file: the system dump file on the system disk if no DUMPFILE_DEVICE is given, or the system dump file on the specified device if DUMPFILE_DEVICE is specified.

On VAX systems, AUTOGEN always creates a minimal SYSDUMP.DMP file on the system disk for error log buffers if DUMPFILE_DEVICE is specified.

On Alpha systems, AUTOGEN only manipulates the size of the error log dump file on the system disk.

If you do not want AUTOGEN to change the sizes of the primary files, specify the following symbols in MODPARAMS.DAT:

PAGEFILE = 0 SWAPFILE = 0 DUMPFILE = 0 ERRLOGDUMP = 0 ! Alpha only

These symbols direct AUTOGEN to ignore the primary page, swap, and dump files when calculating sizes.

If the creation or extension of a system page, swap, or dump file would cause the target disk to become more than 95 percent full, AUTOGEN issues a warning and does not perform the operation.

On Alpha systems, however, the 95 percent rule does not apply to the error log dump file, SYS$ERRLOG.DMP. This file is created if the disk can hold it.

You can use AUTOGEN to create a page, swap, or dump file that is smaller than the current version of the file. After you have booted and begun using the new file, remember to use the DCL command PURGE to reclaim the disk space from the old version of the file.

To determine the current sizes of installed page and swap files, enter the DCL command SHOW MEMORY/FILES. If you increased the size of any of these files and have not rebooted, this command displays the original sizes. Use the DIRECTORY command to determine the size of dump files.

Table 16-4 lists the symbols you can define in MODPARAMS.DAT to control the total size of page file, swap file, system dump file, or error log dump file space space.

Table 16-4 Symbols for Controlling the Total Size of Page, Swap, System Dump, or Error Log Dump File Space

Operation	Page File Symbol	Swap File Symbol	Dump File Symbol	Error Log File Symbol
To define the total amount of space	PAGEFILE = n 1	SWAPFILE = n 1	DUMPFILE = n 1	ERRLOGDUMP = n 1
To increase total size	ADD_PAGEFILE = n	ADD_SWAPFILE = n	ADD_DUMPFILE = n	ADD_ERRLOGDUMP = n
To specify maximum total size	MAX_PAGEFILE = n	MAX_SWAPFILE = n	MAX_DUMPFILE = n	MAX_ERRLOGDUMP = n
To specify minimum total size	MIN_PAGEFILE = n	MIN_SWAPFILE = n	MIN_DUMPFILE = n	MIN_ERRLOGDUMP = n

Table 16-5 lists the symbols you can define in MODPARAMS.DAT to control the size of individual files.

Table 16-5 Symbols for Controlling the Size of Individual Page and Swap Files

Operation	Page File Symbol1	Swap File Symbol1
To specify file size	PAGEFILE n_SIZE = block-size	SWAPFILE n_SIZE = block-size
To increase file size	ADD_PAGEFILE n_SIZE = block-size	ADD_SWAPFILE n_SIZE = block-size
To specify maximum file size	MAX_PAGEFILE n_SIZE = block-size	MAX_SWAPFILE n_SIZE = block-size
To specify minimum file size	MIN_PAGEFILE n_SIZE = block-size	MIN_SWAPFILE n_SIZE = block-size

Examples

1. The following line in MODPARAMS.DAT specifies that all page file space should total 100,000 blocks:

   PAGEFILE = 100000

   
   If you had only a primary page file, the resulting size of that file would be 100,000 blocks. If you had multiple page files, the difference between the total current size and the total new size would be spread across secondary files. For example, if you specified PAGEFILE = 100000, the changed page file sizes would be as follows:

   File	Original Size (in Blocks)	Resulting Size (in Blocks)
   Primary page file	10,000	10,000
   Secondary page file 1	30,000	45,000
   Secondary page file 2	30,000	45,000

2. To direct AUTOGEN to set the primary page file size to 10,000 blocks, use the symbol definition:

   PAGEFILE1_SIZE = 10000

3. To direct AUTOGEN to create a new secondary swap file named PAGED$:[PAGESWAP]SWAPFILE.SYS that holds 30,000 blocks, use the symbol definitions:

   SWAPFILE2_NAME = "PAGED$:[PAGESWAP]SWAPFILE.SYS" MIN_SWAPFILE2_SIZE = 30000

Compaq recommends that you use AUTOGEN to change sizes of system page, swap, and dump files. However, you can use the command procedure SYS$UPDATE:SWAPFILES.COM to change the size of primary system page, swap, and dump files. SWAPFILES.COM shows you the current size of the system page, swap, and dump files before you change the sizes.

If you change the sizes of system page, swap, or dump files, you must edit MODPARAMS.DAT to specify the new sizes, as explained in Section 16.16.1.2. If you do not specify the new sizes in MODPARAMS.DAT, AUTOGEN resizes the files next time it runs.

The procedure displays the sizes of the current system page, swap, and dump files in SYS$SYSTEM, and the amount of space remaining on the system disk. It then allows you to enter new sizes, or keep the existing sizes for these files. If you specify a size that is larger than that of an existing file, the procedure automatically extends the size of a page or dump file. If you specify a smaller size for a system page, swap, or dump file, a new version of the file is created.

How to Perform This Task

1. Enter the following command to invoke the command procedure:

   $ @SYS$UPDATE:SWAPFILES.COM

   
   The system displays the current files found in SYS$SYSTEM and their sizes. For example:

   Current file sizes are: Directory SYS$SYSROOT:[SYSEXE] PAGEFILE.SYS;1 16384 SYSDUMP.DMP;1 4128 SWAPFILE.SYS;1 3072 Total of 3 files, 23584 blocks. There are 128741 available blocks on SYS$SYSDEVICE.

2. In response to the following prompt, type the desired size, in blocks, for the page file. To keep the same size, press Return:

   Enter new size for page file:

3. In response to the following prompt, type the desired size, in blocks, for the dump file. To keep the same size, press Return:

   Enter new size for system dump file:

4. In response to the following prompt, type the desired size, in blocks, for the swap file. To keep the same size, press Return:

   Enter new size for swap file:

5. Shut down and reboot the system to use the new files.
6. After the system reboots, purge obsolete copies of the files. Do not delete the old files until the system reboots.
7. Edit MODPARAMS.DAT to include the new file sizes, as explained in Section 16.16.1.2. If you do not specify the new sizes in MODPARAMS.DAT, AUTOGEN will automatically resize the files the next time it runs.

Example

$ @SYS$UPDATE:SWAPFILES.COM To leave a file size at its current value type a carriage return in response to its size prompt. Current file sizes are: Directory SYS$SYSROOT:[SYSEXE] PAGEFILE.SYS;1 100000 SYSDUMP.DMP;1 28000 SWAPFILE.SYS;1 33000 Total of 3 files, 161000 blocks. There are 128741 available blocks on SYS$SYSDEVICE. Enter new size for page file: [Return] Enter new size for system dump file: 30000 %SYSGEN-I-EXTENDED, SYS$SYSROOT:[SYSEXE]SYSDUMP.DMP;1 extended Enter new size for swap file: [Return] *********************************************************************** * Please reboot in order for the new files to be used by the system. * * After rebooting, purge obsolete copies of the files. * * DO NOT delete the old files until after the reboot. * ***********************************************************************

16.16.3 Using SYSGEN

Compaq recommends that you use AUTOGEN to create and change page, swap, and dump files. AUTOGEN invokes the System Generation utility (SYSGEN) to create or change the files. However, in an emergency, you can use SYSGEN to directly change the size of page, swap and dump files. For example, if you see that page file space is becoming dangerously low, you might use SYSGEN to quickly add page file space to prevent the system from hanging.

How to Perform This Task

1. Determine the location and appropriate size of the files. For information, see Section 16.4.
2. Invoke SYSGEN and enter the CREATE command in the following format:

   CREATE file-spec/SIZE=block-count

   
   where:
   file-spec specifies the full file specification.
   block-count specifies the size of the file in blocks.
   If the file you specify already exists and the size you specify is larger than the existing file, the command extends the existing file. If the file you specify already exists and the size you specify is smaller than the existing file, the command creates a new file of the specified size.
   For example, the following command extends the existing, smaller primary page file PAGEFILE.SYS:

   SYSGEN> CREATE PAGEFILE.SYS/SIZE=100000

   
   For more information about the SYSGEN command CREATE, refer to the SYSGEN section in the OpenVMS System Management Utilities Reference Manual.

   Note Frequent file creation and deletion can cause the free space on a disk to become severely fragmented. SYSGEN issues a HEADERFULL warning message if it determines that the creation or extension of a system file would cause that file to become fragmented enough to render the system unbootable. If this occurs, Compaq recommends that you back up and restore your system disk to consolidate the free space on the volume into one contiguous area. For more information, see Section 11.17. After you restore the disk, retry the SYSGEN operation. When SYSGEN issues a warning message, the file might be somewhat larger, but not as large as the value specified in the CREATE command.

3. Use the following table to determine if you should reboot to use the new or modified file:

   Type	Change	Reboot Required?
   Primary page, swap, system dump, or error log dump file 1	New file	Yes
   	Extended file	Yes
   Secondary page or swap file	New file	No 2
   	Extended file	Yes
   Alternate (DOSD) dump file (Alpha)	New file	No
   	Extended file	No
   Alternate (DOSD) dump file (VAX)	New file	Yes
   	Extended file	Yes

   ---

   ¹Primary page, swap, and dump files are SYS$SPECIFIC:[SYSEXE] PAGEFILE.SYS, SWAPFILE.SYS, SYSDUMP.DMP; and SYS$ERRLOG.DMP.
   ²Although rebooting the system is unnecessary, you must install secondary files before the system can use them. For more information, see Section 16.14.
   

   ---

4. If you create a new version of the file, purge the old version after the system reboots.
5. Add commands to the site-specific startup command procedure SYPAGSWPFILES.COM to make sure the files are installed each time the system boots. For instructions, see Section 16.14.
6. If you do not want AUTOGEN to resize the files according to its calculations, edit MODPARAMS.DAT to specify the sizes of these files. Follow the instructions in Section 16.16.1.2.

Example

The commands in the following example extend the existing files PAGEFILE.SYS, SWAPFILE.SYS, and SYSDUMP.DMP to the specified sizes:

$ RUN SYS$SYSTEM:SYSGEN SYSGEN> CREATE PAGEFILE.SYS/SIZE=100000 %SYSGEN-I-EXTENDED, SYS$SYSROOT:[SYSEXE]PAGEFILE.SYS;1 extended SYSGEN> CREATE SWAPFILE.SYS/SIZE=30000 %SYSGEN-I-EXTENDED, SYS$SYSROOT:[SYSEXE]SWAPFILE.SYS;1 extended SYSGEN> CREATE SYSDUMP.DMP/SIZE=33000 %SYSGEN-I-EXTENDED, SYS$SYSROOT:[SYSEXE]SYSDUMP.DMP;1 extended SYSGEN> EXIT

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