Document revision date: 15 July 2002

The following list describes optional system management operations normally performed after installation. These operations often result in improved overall performance. Choose the options that are appropriate for your site. Not all options are appropriate at every site.

• Expand system libraries --- Most large libraries ship on the operating system in a data-reduced (compressed) format to conserve disk space. Unless the files are expanded (decompressed), the system must dynamically expand them each time they are accessed. The resulting performance slowdown is especially noticeable during link operations and requests to online help. If your system has sufficient disk space, expanding the libraries improves both CPU and elapsed time performance. For details about expanding system libraries and using the LIBDECOMP.COM command procedure, see Section 17.9.
• Disable file system high-water marking---This security feature is set by default when a volume is initialized to guarantee that users cannot read data they have not written.
  For nonshared sequential files, the performance impact of high-water marking is minimal. However, for files of nonsequential format, high-water marking creates some overhead; the system erases the previous contents of the disk blocks allocated every time a file is created or extended.
  Disabling the feature improves system performance by a variable amount, depending on the following factors:
  • How frequently new files are created
  • For indexed and relative files, how frequently existing files are extended
  • How fragmented the volume is
  
  Be sure to consider the security implications before you disable high-water marking.
  To disable high-water marking, you can specify the /NOHIGHWATER qualifier when initializing the volume, or you can disable high-water marking with the DCL command SET VOLUME in the following format:

  SET VOLUME/NOHIGHWATER_MARKING device-name[:]

• Set file extend parameters for OpenVMS Record Management Services (RMS)---Because files extend in increments of twice the multiblock count (default 16), system defaults provide file extension of 32 blocks rounded up to the nearest multiple of the disk's cluster size. Thus, when files are created or extended, increased I/O may slow performance. The problem can be corrected by specifying larger values for file extend parameters or by setting the system parameter RMS_EXTEND_SIZE. See Section 15.5 for information about modifying system parameters. Refer to the OpenVMS System Management Utilities Reference Manual for a description of all system parameters.
  For more detailed information about establishing the file extension quantity, refer to the section on tuning in the Guide to Creating OpenVMS Modular Procedures.
• Install frequently used images---When an image is accessed concurrently by more than one process on a routine basis, install the image with the Install utility (INSTALL), specifying the /OPEN, /SHARED, and /HEADER_RESIDENT qualifiers. You will thereby ensure that all processes use the same physical copy of the image, and that the image will be activated in the most efficient way.
  Generally, an image takes about two additional physical pages when installed with the /OPEN, /HEADER_RESIDENT, and /SHARED qualifiers. The utility's LIST/FULL command shows the highest number of concurrent accesses to an image installed with the /SHARED qualifier. This information can help you decide whether installing an image is an efficient use of memory.
  See Section 17.10.11 and the INSTALL section of OpenVMS System Management Utilities Reference Manual for more information about installing images.
• On Alpha systems, install shareable and executable images specifying the /RESIDENT qualifier with the Install utility. For more information, see Section 17.10.6.
  Note that this is a tradeoff between the CPU and memory. Installing an image with /RESIDENT qualifier means that the code is to be nonpaged. Depending on the amount of sharing, this is can be a memory gain or loss.
• Reduce system disk I/O---You can move frequently accessed files off the system disk and use logical names to specify the location or, where necessary, other pointers to access them. For example:
  • SYSUAF.DAT (SYSUAF is the logical name)
  • RIGHTSLIST.DAT (RIGHTSLIST is the logical name)
  • VMSMAIL_PROFILE.DATA (VMSMAIL_PROFILE is the logical name)
  • NETPROXY.DAT (NETPROXY is the logical name)
  • NET$PROXY.DAT (NET$PROXY is the logical name)
  • The queue database (for more information, see Section 13.3)
  • ERRFMT log files (SYS$ERRORLOG is the logical name)
  • MONITOR log files (SYS$MONITOR is the logical name)
  • The accounting log file (ACCOUNTNG is the logical name)
  • SECURITY_AUDIT.AUDIT$JOURNAL (SET AUDIT/JOURNAL=SECURITY/DESTINATION= filespec)
  • Default DECnet for OpenVMS accounts (records included in the SYSUAF file on the OpenVMS distribution kit)
  To redefine logical names for these system files, edit the site-specific command procedure SYS$MANAGER:SYLOGICALS.COM. For more information about defining logical names in SYLOGICALS.COM, see Section 5.2.5.
  You can also consider moving paging and swapping activity off the system disk by creating large secondary page and swap files on a less heavily used disk. However, if you want to store crash dumps for diagnosing system failures, the dump file must reside in the system-specific directory SYS$SPECIFIC:[SYSEXE] on the system disk for storing crash dumps; if no dump file exists in SYS$SPECIFIC:[SYSEXE], the primary page file must be located there if you want to store crash dumps. For detailed information about moving page and swap files, see Section 16.16.
• On Alpha systems, set aside large amounts of memory for use within memory-resident sections. The Reserved Memory Registry through its interface within the SYSMAN utility allows an OpenVMS Alpha system to be configured with large amounts of memory set aside for use within memory-resident sections and by other privileged applications. The Reserved Memory Registry also allows an OpenVMS system to be properly tuned through the AUTOGEN utility, taking into account the preallocated reserved memory. For more information, see Section 17.11.

Some of the larger system libraries are shipped with the OpenVMS operating system in a data-reduced (compressed) format. Expanding (that is, decompressing) these libraries gives the system faster access to them but also consumes more disk space. To learn how to determine whether you have enough disk space to expand some or all libraries, refer to Section 17.9.1.

If you have delete access to the existing libraries and write access to the library directories, you can use either of the following methods to expand and reduce (compress) libraries:

• Run the LIBDECOMP.COM command procedure (see Section 17.9.2), which can expand or reduce one, some, or all of the selected libraries that ship in data-reduced (compressed) format.
• Enter the DCL command LIBRARY with the /DATA qualifier (see Section 17.9.3) to expand or reduce one library at a time, including libraries that do not ship in data-reduced format.

Before you expand any libraries, make sure your system has enough free disk space to accommodate the expanded files. To find out how much free disk space you have, enter the following command:

$ SHOW DEVICE SYS$SYSDEVICE

The amount of space required to expand all the libraries that ship in data-reduced format differs, depending on your operating system and configuration. For Alpha systems, you need approximately 60,000 free disk blocks; VAX systems require less. For specific disk requirements, refer to the Upgrade and Installation Manual for your operating system.

If you have less free disk space than is required, or if you do not want to expand all the system libraries, you can choose to expand only some of them. For example, you might expand only the system help library (HELPLIB.HLB) and other libraries that are used frequently on your system, and leave the rest in data-reduced format.

17.9.2 Using the Library Decompression Utility (LIBDECOMP.COM)

The Library Decompression utility is a command procedure, LIBDECOMP.COM, located in the SYS$UPDATE directory. LIBDECOMP.COM uses LIBRARY commands to expand (decompress) or reduce (compress) any or all of the system libraries that ship in data-reduced format. (For a list of these libraries, see Section 17.9.2.1.)

The LIBDECOMP.COM command procedure allows you to enter one command instead of multiple LIBRARY commands to expand or reduce all or many libraries in one operation. LIBDECOMP.COM can be executed interactively (see Section 17.9.2.2) or in batch mode (see Section 17.9.2.3).

17.9.2.1 Libraries on which LIBDECOMP.COM Operates

The Library Decompression utility works on a selected set of large libraries --- those that ship in data-reduced format. Some libraries are platform specific and ship only on VAX systems or only on Alpha systems. Many libraries are optional components and may not be present on your system if all options were not selected when OpenVMS was installed. Table 17-1 lists all the libraries known to LIBDECOMP.COM on both VAX and Alpha systems.

Table 17-1 Libraries Recognized by LIBDECOMP.COM

Library Name	Platform	Description
[SYSHLP] directory; help library files (.HLB)
ACLEDT.HLB	Both	Access Control List Editor help
BKM$HELP.HLB	Both	Backup Manager help
DBG$HELP.HLB	Both	OpenVMS Debugger help
DBG$UIHELP.HLB	Both	OpenVMS Debugger help
EDTHELP.HLB	Both	EDT editor help
EVE$HELP.HLB	Both	EVE editor help
EVE$KEYHELP.HLB	Both	EVE keypad help
EXCHNGHLP.HLB	Both	Exchange utility help
HELPLIB.HLB	Both	DCL help
LANCP$HELP.HLB	Both	LAN Control Program help
LATCP$HELP.HLB	Both	LAT Control Program help
MAILHELP.HLB	Both	Mail utility help
NCPHELP.HLB	Both	Network Control Program help
SDA.HLB	Both	System Dump Analyzer help
SHWCLHELP.HLB	Both	Show Cluster utility help
SYSGEN.HLB	Both	System Generation utility help
SYSMANHELP.HLB	Both	System Management utility help
TPUHELP.HLB	Both	Text Processing Utility help
UAFHELP.HLB	Both	Authorize utility help
[SYSLIB] directory; macro library files (.MLB)
LANIDEF.MLB	Alpha only	LAN internal driver macros
LIB.MLB	Both	Operating system macros
STARLET.MLB	Both	Operating system macros
SYSBLDMLB.MLB	VAX only	System build files
[SYSLIB] directory; object library files (.OLB)
DECCRTL.OLB	VAX only	Compaq C Run-time Library
STARLET.OLB	Both	System object library and run-time library
SYSBLDLIB.OLB	VAX only	System build files
VAXCRTL.OLB	Both	Compaq C RTL routine name entry points; VAX G_floating double-precision, floating-point entry points
VAXCRTLD.OLB	Alpha only	Limited support of VAX D_floating double-precision, floating-point entry points
VAXCRTLDX.OLB	Alpha only	VAX D_floating support; support for /L_DOUBLE_SIZE=128 compiler qualifier
VAXCRTLT.OLB	Alpha only	IEEE T_floating double-precision, floating-point entry points
VAXCRTLTX.OLB	Alpha only	IEEE T_floating support; support for /L_DOUBLE_SIZE=128 compiler qualifier
VAXCRTLX.OLB	Alpha only	G_floating support; support for /L_DOUBLE_SIZE=128 compiler qualifier
VMS$VOLATILE_PRIVATE_INTERFACES.OLB	Alpha only	OpenVMS bugcheck processing codes
[SYSLIB] directory; text library files (.TLB)
ERFLIB.TLB	Both	ANALYZE/ERROR device descriptions
LIB_ADA_SUBSET.TLB	Both	Ada programmers toolkit of operating system definitions
NTA.TLB	Both	Files to build against NTA facility
STARLET_RECENT_ADA_SUBSET.TLB	Both	Ada programmers toolkit of operating system definitions
STARLETSD.TLB	Both	STARLET definitions used during layered product installations
SYS$LIB_C.TLB	Alpha only	Header files for C language; derived from LIB
SYS$STARLET_C.TLB	Both	Public header files for Compaq C

You can use the list function of the LIBDECOMP.COM command procedure to output a list of all libraries known to the Library Decompression utility, including their size and status on your system. For details and an example, see Section 17.9.2.2.1.

17.9.2.2 Using LIBDECOMP.COM Interactively

The basic command to run the Library Decompression utility is as follows:

@SYS$UPDATE:LIBDECOMP [parameters]

The Library Decompression utility accepts up to eight optional parameters. The first parameter controls which of the utility's three functions is performed. Additional parameters control which libraries the utility processes. The three functions are described in the following sections:

• List function (see Section 17.9.2.2.1)
  Lists all VAX and Alpha libraries known to the Library Decompression utility and displays the size and status (reduced or expanded) of libraries on your system.
• Expand function (see Section 17.9.2.2.2)
  Expands libraries that are in data-reduced format. This is the default function.
• Reduce function (see Section 17.9.2.2.3)
  Compresses expanded libraries into data-reduced format.

To get a brief online help display, enter the following command:

$ @SYS$UPDATE:LIBDECOMP HELP

17.9.2.2.1 Listing Libraries

To list all VAX and Alpha libraries known to the Library Decompression utility, along with their size and status on your system, specify the LIST parameter in the command, as follows:

$ @SYS$UPDATE:LIBDECOMP LIST

The resulting list indicates which libraries are not present on your system, either because they do not ship with VAX or with Alpha or because the facility associated with them is not installed on your system. For libraries that are present, the list includes the library size and the current status (reduced or expanded). The following example shows the output from an Alpha system. (Note: File sizes are subject to change. For the most accurate information, refer to the LIST output on your own system.)

$ @SYS$UPDATE:LIBDECOMP LIST OpenVMS Library Decompression Utility List of all libraries known to LIBDECOMP "Library not present" indicates not installed on this system Libraries in SYS$SYSROOT: Library Size 1) [SYSHLP]ACLEDT.HLB 70 Reduced format 2) [SYSHLP]BKM$HELP.HLB 156 Reduced format 3) [SYSHLP]DBG$HELP.HLB 1234 Reduced format 4) [SYSHLP]DBG$UIHELP.HLB 269 Reduced format 5) [SYSHLP]EDTHELP.HLB 154 Reduced format 6) [SYSHLP]EVE$HELP.HLB 676 Reduced format 7) [SYSHLP]EVE$KEYHELP.HLB 99 Reduced format 8) [SYSHLP]EXCHNGHLP.HLB 83 Reduced format 9) [SYSHLP]HELPLIB.HLB 9179 Reduced format 10) [SYSHLP]LANCP$HELP.HLB 119 Reduced format 11) [SYSHLP]LATCP$HELP.HLB 157 Reduced format 12) [SYSHLP]MAILHELP.HLB 211 Reduced format 13) [SYSHLP]NCPHELP.HLB 261 Reduced format 14) [SYSHLP]SDA.HLB 308 Reduced format 15) [SYSHLP]SHWCLHELP.HLB 103 Reduced format 16) [SYSHLP]SYSGEN.HLB 337 Reduced format 17) [SYSHLP]SYSMANHELP.HLB 492 Reduced format 18) [SYSHLP]TPUHELP.HLB 575 Reduced format 19) [SYSHLP]UAFHELP.HLB 241 Reduced format 20) [SYSLIB]LANIDEF.MLB 181 Reduced format 21) [SYSLIB]LIB.MLB 2715 Reduced format 22) [SYSLIB]STARLET.MLB 2335 Reduced format 23) [SYSLIB]SYSBLDMLB.MLB Library not present 24) [SYSLIB]DECCRTL.OLB Library not present 25) [SYSLIB]STARLET.OLB 27461 Reduced format 26) [SYSLIB]SYSBLDLIB.OLB Library not present 27) [SYSLIB]VAXCRTL.OLB 1163 Reduced format 28) [SYSLIB]VAXCRTLD.OLB 1587 Reduced format 29) [SYSLIB]VAXCRTLDX.OLB 1506 Reduced format 30) [SYSLIB]VAXCRTLT.OLB 1434 Reduced format 31) [SYSLIB]VAXCRTLTX.OLB 1449 Reduced format 32) [SYSLIB]VAXCRTLX.OLB 1285 Reduced format 33) [SYSLIB]ERFLIB.TLB 64 Reduced format 34) [SYSLIB]LIB_ADA_SUBSET.TLB 1839 Reduced format 35) [SYSLIB]NTA.TLB 34 Reduced format 36) [SYSLIB]STARLETSD.TLB 3940 Reduced format 37) [SYSLIB]SYS$LIB_C.TLB 9442 Reduced format 38) [SYSLIB]SYS$STARLET_C.TLB 5864 Reduced format 39) [SYSLIB]VMS$VOLATILE_PRIVATE_INTERFACES.OLB 445 Reduced format 40) [SYSLIB]STARLET_RECENT_ADA_SUBSET.TLB 1100 Reduced format Total Libraries: 37 78568

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