HP OpenVMS System Management Utilities Reference Manual


Previous Contents Index

The default value of 7 preserves compatibility with existing DECwindows Motif behavior. A value of 0 disables all unevaluated configurations.

SETTIME

SETTIME enables (1) or disables (0) solicitation of the time of day each time the system is booted. This parameter should usually be off (0), so that the system sets the time of day at boot time to the value of the processor time-of-day register. You can reset the time after the system is up with the DCL command SET TIME (see the HP OpenVMS DCL Dictionary).

SHADOW_D1-D5 (D)

Special DYNAMIC parameters reserved for HP use.

SHADOW_ENABLE

Special parameter reserved for HP use.

SHADOWING

SHADOWING loads the host-based volume shadowing driver. See HP Volume Shadowing for OpenVMS for more information about setting system parameters for volume shadowing.

Specify one of the following values:
Value Description
0 No shadowing is enabled; SHDRIVER is not loaded. This is the default value.
2 Host-based volume shadowing enabled; SHDRIVER is loaded. Host-based volume shadowing provides shadowing of all disks located on a standalone system or an OpenVMS Cluster system.

SHADOW_HBMM_RTC (D)

(Alpha and Integrity servers) SHADOW_HBMM_RTC specifies, in seconds, how frequently each shadow set on this system has its modified block count compared with the reset threshold. If the modified block count exceeds the reset threshold, the bitmap for that shadow set is zeroed. This comparison is performed for all shadow sets mounted on the system that have HBMM bitmaps.

The reset threshold is specified by the RESET_THRESHOLD keyword in the /POLICY qualifier of the SET SHADOW command.

When the comparison is made, the modified block count might exceed the reset threshold by a small increment or by a much larger amount. The difference depends on the write activity to the volume and on the setting of this parameter.

SHADOW_MAX_COPY (A,D)

The value of SHADOW_MAX_COPY controls how many parallel copy threads are allowed on a given node.

Carefully consider the needs of each shadowed node when you set this parameter. Too high a value for SHADOW_MAX_COPY can affect performance by allowing too many copy threads to operate in parallel. Too low a value unnecessarily restricts the number of threads your system can effectively handle.

See HP Volume Shadowing for OpenVMS for more information about setting system parameters for volume shadowing.

SHADOW_MAX_UNIT

SHADOW_MAX_UNIT specifies the maximum number of shadow sets that can exist on a system. The setting must be equal to or greater than the number of shadow sets you plan to have on a system. Dismounted shadow sets, unused shadow sets, and shadow sets with no write bitmaps allocated to them are included in the total.

Note

Review this default carefully. The setting must be equal to or greater than the number of shadow sets you plan to have on a system. If you attempt to mount more shadow sets than the number specified by SHADOW_MAX_UNIT, the MOUNT command will fail. Dismounted shadow sets, unused shadow sets, and shadow sets with no write bitmaps allocated to them are included in the count for SHADOW_MAX_UNIT.

On Alpha and Integrity servers, the default value for this system parameter is 500, which consumes 24 KB of main memory.

If you do not plan to use Volume Shadowing for OpenVMS, you can change the setting to its minimum of 10 (which consumes 480 bytes of main memory). Setting the default to its minimum frees up 23.5 KB of main memory on an OpenVMS Alpha or Integrity servers and 4.5 KB of main memory on a VAX system. (The maximum value of this parameter is 10,000.)

This system parameter is not dynamic; that is, a reboot is required when you change the setting.

SHADOW_MBR_TMO (D)

SHADOW_MBR_TMO controls the amount of time the system tries to fail over physical members of a shadow set before removing them from the set. The SHADOW_MBR_TMO parameter replaces the temporary VMSD3 parameter used in prior releases.

The SHADOW_MBR_TMO parameter is valid for use only with Phase II of Volume Shadowing for OpenVMS. You cannot set this parameter for use with Phase I, which is obsolete.

Use the SHADOW_MBR_TMO parameter (a word) to specify the number of seconds, in decimal from 1 to 65,535, during which recovery of a repairable shadow set is attempted. If you do not specify a value or if you specify 0, the default delay of 120 seconds is used.

Because SHADOW_MBR_TMO is a dynamic parameter, you should use the SYSGEN command WRITE CURRENT to permanently change its value.

SHADOW_PSM_RDLY

When a copy or merge operation is needed on a shadow set that is mounted on more than one system, the shadowing driver attempts to perform the operation on a system that has a local connection to all the shadow set members. Shadowing implements the copy or merge operation by adding a time delay based on the number of shadow set members that are MSCP-served to the system. No delay is added for local members; a system with all locally accessible shadow set members usually performs the copy or merge before a system on which one or more members is served (and therefore is delayed) does.

SHADOW_PSM_RDLY allows the system manager to adjust the delay that shadowing adds. By default, the delay is 30 seconds for each MSCP-served shadow set member. The valid range for the specified delay is 0 through 65,535 seconds.

When a shadow set is mounted on a system, the value of SHADOW_PSM_RDLY is used as the default shadow set member recovery delay for that shadow set. To modify SHADOW_PSM_RDLY for an existing shadow set, see the SET SHADOW/ /RECOVERY_OPTIONS=DELAY_PER_SERVED_MEMBER=n command in HP Volume Shadowing for OpenVMS.

SHADOW_REC_DLY (D)

(Alpha and Integrity servers)

The value of the SHADOW_REC_DLY parameter specifies the length of time a system waits before it attempts to manage recovery operations on shadow sets that are mounted on the system. A shadow set is said to need recovery when a merge or copy operation is required on that shadow set.

SHADOW_REC_DLY can be used to better predict which systems in an OpenVMS Cluster performs recovery operations. This is done by setting lower values of SHADOW_REC_DLY on systems that are preferred to handle recovery operations and higher values of SHADOW_REC_DLY on systems that are least preferred to handle recovery operations.

The range of SHADOW_REC_DLY is 20 to 65535 seconds. The default value is 20 seconds.

For more information about controlling which systems perform the merge or copy operations, see HP Volume Shadowing for OpenVMS.

SHADOW_SITE_ID (D)

(Alpha and Integrity servers) This parameter allows a system manager to define a site value, which Volume Shadowing uses to determine the best device to perform reads, thereby improving performance.

The system manager can now define the site value to be used for all shadow sets mounted on a system. This parameter is an arbitrary numeric value coordinated by the system manager of disaster tolerant clusters. Reads from devices that have site values matching the shadow set's site value are preferred over reads from devices with different site values. For detailed information, see the description of the $SET DEVICE/SITE in the HP OpenVMS DCL Dictionary and HP Volume Shadowing for OpenVMS.

SHADOW_SYS_DISK

A SHADOW_SYS_DISK parameter value of 1 enables shadowing of the system disk. A value of 0 disables shadowing of the system disk. The default value is 0.

Also specify a system disk shadow set virtual unit number with the SHADOW_SYS_UNIT system parameter, unless the desired system disk unit number is DSA0.

A value of 4096 enables CI-based minimerge. To enable minimerge on a system disk, however, you must enable DOSD by setting the DUMPSTYLE parameter to dump off system disk, as described in the HP OpenVMS System Manager's Manual. You can then add the value 4096 to your existing SHADOW_SYS_DISK value. For example, if you have SHADOW_SYS_DISK set to a value of 1, change it to 4097 to enable minimerge.

SHADOW_SYS_TMO

The SHADOW_SYS_TMO parameter has the following two distinct uses:

This parameter applies only to members of the system disk shadow set. All nodes using a particular system disk shadow set should have their SHADOW_SYS_TMO parameter set to the same value once normal operations begin.

The default value is 120 seconds. Change this parameter to a higher value if you want the system to wait more than the 120-second default for all members to join the shadow set. You can set the parameter value to 120 through 65,535 seconds.

SHADOW_SYS_UNIT

Use this parameter for Phase II shadowing only. The SHADOW_SYS_ UNIT parameter is an integer value that contains the virtual unit number of the system disk. The default value is 0. The maximum value allowed is 9999. This parameter is effective only when the SHADOW_SYS_DISK parameter has a value of 1. This parameter should be set to the same value on all nodes booting off a particular system disk shadow set. See HP Volume Shadowing for OpenVMS for more information about setting system parameters for volume shadowing.

SHADOW_SYS_WAIT

The SHADOW_SYS_WAIT parameter extends the time a booting system waits for all current members of a mounted shadowed system disk to become available to this node. The shadow set must already be mounted by at least one other cluster node for this parameter to take effect.

The default value is 480 seconds. Change this parameter to a higher value if you want the system to wait more than the 480-second default for all members to join the shadow set. You can set the parameter value to 1 through 65,535 seconds.

SMCI_FLAGS (D)

(Alpha Galaxy platforms only) The SMCI_FLAGS parameter controls operational aspects of SYS$PBDRIVER, the Galaxy Shared Memory Cluster Interconnect (SMCI).

Bits in the bit mask are the following:
Bit Mask Description
0 0 0 = Do not create local communications channels (SYSGEN default). Local SCS communications are primarily used in test situations and are not needed for normal operations. Not creating local communications saves resources and overhead.
    1 = Create local communications channels.
1 2 0 = Load SYS$PBDRIVER if booting into both a Galaxy and a Cluster (SYSGEN Default).
    1 = Load SYS$PBDRIVER if booting into a Galaxy.
2 4 0 = Minimal console output (SYSGEN default).
    1 = Full console output; SYS$PBDRIVER displays console messages when it creates and tears down communications channels.

SMCI_PORTS

On systems running OpenVMS Galaxy software, the Shared Memory Cluster Interconnect (SMCI) system parameter SMCI_PORTS controls initial loading of SYS$PBDRIVER. This parameter is a bit mask; bits 0 through 25 each represent a controller letter. If bit 0 is set, which is the default setting, PBAx is loaded (where x represents the Galaxy Partition ID). If bit 1 is set, PBBx is loaded, and so on up to bit 25, which causes PBZx to be loaded. For OpenVMS Alpha Version 7.2 and later, HP recommends leaving this parameter at the default value of 1.

Loading additional ports allows multiple paths between Galaxy instances. In the initial release of the Galaxy software, having multiple communications channels is not an advantage because SYS$PBDRIVER does not support fast path. A future release of OpenVMS will provide Fast Path support for SYS$PBDRIVER, when multiple CPUs improve throughput by providing multiple communications channels between instances.

SMP_CPU_BITMAP

This parameter indicates that the corresponding CPU is a bitmap representing up to 1024 CPUs. Each bit set in this bitmap indicates that the corresponding CPU automatically attempts to join the active set in an OpenVMS symmetric multiprocessing environment when the instance is booted. A cleared bit indicates that the corresponding CPU is ignored only at boot time; if it is otherwise viable, the CPU can be started at a later time.

SMP_CPU_BITMAP defaults to all bits set. (CPU 0 through CPU 1023 are enabled for multiprocessing.) Note that the primary processor is always booted regardless of the setting of the corresponding bit in the CPU bitmap.

To change the value of SMP_CPU_BITMAP in SYSBOOT or SYSGEN, specify a list of individual bits or contiguous groups of bits. For example:


   SYSGEN> SET SMP_CPU_BITMAP 0,5,17-21 

The command in this example sets bits 0, 5, 17, 18, 19, 20, and 21 in the bitmap and clears all other bits.

This parameter replaces the SMP_CPUS parameter.

SMP_LNGSPINWAIT

SMP_LNGSPINWAIT establishes, in 10-microsecond intervals, the amount of time a CPU in an SMP system normally waits for access to a shared resource. This process is called spinwaiting.

Generally spinlocks at IPL <= 8 have long holding times, therefore have their timeout intervals set to SMP_LNGSPINWAIT to prevent SPINWAIT timeouts in cases of nested acquisition.

A timeout causes a CPUSPINWAIT bugcheck.

The default value is 3000000 (30,00, 000 10-microsecond intervals or 30 second).

SMP_SANITY_CNT

SMP_SANITY_CNT establishes, in 10-millisecond intervals, the timeout period for each CPU in a symmetric multiprocessing (SMP) system. Each CPU in an SMP system monitors the sanity timer of one other CPU in the configuration to detect hardware or software failures. If allowed to go undetected, these failures could cause the cluster to hang. A timeout causes a CPUSANITY bugcheck.

The default value is 300 milliseconds (30 10-millisecond intervals).

SMP_SPINWAIT

SMP_SPINWAIT establishes, in 10-microsecond intervals, the amount of time a CPU in an SMP system normally waits for access to a shared resource. This process is called spinwaiting.

A timeout causes a CPUSPINWAIT bugcheck.

The default value is 100000 (100,000 10-microsecond intervals or 1 second).

SMP_TICK_CNT

SMP_TICK_CNT sets the frequency of sanity timer checks by each CPU in a multiprocessing system.

This special parameter is used by HP and is subject to change. Do not change this parameter unless HP recommends that you do so.

SSI_ENABLE

(Integrity servers only) This parameter controls the usage of system service interception. SSI_ENABLE is turned on by default.

System Service Interception is a mechanism that allows user specified code to run before, after or instead of the intercepted system service. This mechanism is available on OpenVMS Alpha Version 6.1 and later and OpenVMS Integrity servers Version 8.3 and later, but the parameter SSI_ENABLE is relevant only on Integrity server systems.

SSINHIBIT

SSINHIBIT controls whether system services are inhibited (1) (on a per-process basis). By default, system services are not inhibited (0).

This special parameter is used by HP and is subject to change. Do not change this parameter unless HP recommends that you do so.

STARTUP_P1--8

The following table describes possible values of STARTUP_P1 through _P8:
STARTUP Value Description
STARTUP_P1 Specifies the type of system boot the system-independent startup procedure is to perform when STARTUP_P1 has one of the following values:
  • " "-- A full boot is performed.
  • "MIN"-- A minimum boot that starts only what is absolutely necessary for the operating system to run.
STARTUP_P2 Controls the setting of verification during the execution of the system-independent startup procedure, STARTUP.COM, when STARTUP_P2 has one of the values described in the lists below.

STARTUP_P2 can be one of the values shown in the following list:

  • F[ALSE], N[O], 0, " "---Verification is not enabled; in other words, NOVERIFY is performed.
  • T[RUE], Y[ES], 1---Verification is enabled; in other words, a SET VERIFY is performed.

Alternatively, STARTUP_P2 can be a string containing one or more of the letters shown in the following list:

  • C---Display various checkpointing messages during startup.
  • D---Log (or Dump) the output from the startup to a file called SYS$SPECIFIC:[SYSEXE]STARTUP.LOG.
  • P---DCL verification is enabled for each component file, but not for the startup driver. If both P and V are used, P is ignored.
  • V---Full DCL verification is enabled; same as TRUE.

For more information about STARTUP_P2, see the SYSMAN command STARTUP SET OPTIONS.

STARTUP_P3 Beginning in OpenVMS Version 7.2, if STARTUP_P3 is set to AGEN, the system executes AUTOGEN at the end of the startup sequence.
STARTUP_P4
through
STARTUP_P8
Reserved for future use.

SWP_PRIO

SWP_PRIO sets the priority of I/O transfers initiated by the swapper.

This special parameter is used by HP and is subject to change. Do not change this parameter unless HP recommends that you do so.

SWPFAIL

SWPFAIL sets the number of consecutive swap failures allowed before the swap schedule algorithm is changed to ignore the swap quantum protection.

This special parameter is used by HP and is subject to change. Do not change this parameter unless HP recommends that you do so.

SWPOUTPGCNT (A on VAX,D)

This parameter allows the swapper an alternative mechanism before actually performing swaps.

On Alpha and Integrity servers, SWPOUTPGCNT defines the minimum number of pagelets to which the swapper should attempt to reduce a process before swapping it out. The pagelets taken from the process are placed into the free-page list.

SWPRATE

SWPRATE sets the swapping rate (in 10-millisecond units). This parameter limits the amount of disk bandwidth consumed by swapping.

This special parameter is used by HP and is subject to change. Do not change this parameter unless HP recommends that you do so.

SYSMWCNT (A,G,M)

SYSMWCNT sets the quota for the size of the system working set, which contains the pageable portions of the system, the paged dynamic pool, RMS, and the resident portion of the system message file.

While a high value takes space away from user working sets, a low value can seriously impair system performance. Appropriate values vary, depending on the level of system use. When the system is running at full load, check the rate of system faults with the MONITOR PAGE command of the Monitor utility. An average system page fault rate of between 0 and 3 page faults per second is desirable. If the system page fault rate is high, and especially if the system seems to be slow, you should increase the value of SYSMWCNT. However, do not set this parameter so high that system page faulting never occurs.

SYSPFC

SYSPFC sets the number of pages to be read from disk on each system paging operation.

This special parameter is used by HP and is subject to change. Do not change this parameter unless HP recommends that you do so.

SYSSER_LOGGING (D)

(Alpha and Integrity servers) A value of 1 for SYSSER_LOGGING enables logging of system service requests for a process. The default is 1.

SYSTEM_CHECK

SYSTEM_CHECK investigates intermittent system failures by enabling a number of run-time consistency checks on system operation and recording some trace information.

Enabling SYSTEM_CHECK causes the system to behave as if the following system parameter values are set (although the values of the following parameters are not actually changed):
Parameter Value Description
BUGCHECKFATAL 1 Crash the system on nonfatal bugchecks.
POOLCHECK %X616400FF Enable all poolchecking, with an allocated pool pattern of %x61616161 ('aaaa') and deallocated pool pattern of x64646464 ('dddd').
MULTIPROCESSING 2 Enable full synchronization checking.

While SYSTEM_CHECK is enabled, the previous settings of the BUGCHECKFATAL and MULTIPROCESSING parameters are ignored. However, setting the parameter POOLCHECK to a nonzero value overrides the setting imposed by SYSTEM_CHECK.

Setting SYSTEM_CHECK creates certain image files that are capable of the additional system monitoring. These image files are located in SYS$LOADABLE_IMAGES and can be identified by the suffix _MON. For information about the type of data checking performed by SYSTEM_CHECK, see the description of the ACP_DATACHECK parameter. For information about the performance implications of enabling SYSTEM_CHECK, see OpenVMS Performance Management.

TAPE_ALLOCLASS

TAPE_ALLOCLASS determines the tape allocation class for the system. The tape allocation class creates a unique clusterwide device name for multiple access paths to the same tape.

The TAPE_ALLOCLASS parameter can also be used to generate a unique clusterwide name for tape devices with identical unit numbers.

TAPE_MVTIMEOUT (D)

TAPE_MVTIMEOUT is the time in seconds that a mount verification attempt continues on a given magnetic tape volume. If the mount verification does not recover the volume within that time, the I/O operations outstanding to the volume terminate abnormally.

TBSKIPWSL

TBSKIPWSL specifies the maximum number of working set list entries that may be skipped while scanning for a "good" entry to discard. Setting this parameter to 0 disables skipping.

This special parameter is used by HP and is subject to change. Do not change this parameter unless HP recommends that you do so.

TIME_CONTROL (D)

This special parameter is used by HP and is subject to change. Do not change this parameter unless HP recommends that you do so.

TIME_CONTROL is an SMP bit mask parameter that controls debugging functions. The following bits are defined:
Bit Description
0 Obsolete.
1 (EXE$V_SANITY) Disables the SMP sanity timer support.
2 (EXE$V_NOSPINWAIT) Disables the functional behavior of the SMP spinwait support.

TIMEPROMPTWAIT

TIMEPROMPTWAIT defines the number of seconds that you want a processor to wait for the time and date to be entered when a system boot occurs, if the processor's time-of-year clock does not contain a valid time. (The time unit of micro-fortnights is approximated as seconds in the implementation.) If the time specified by TIMEPROMPTWAIT elapses, the system continues the boot operation, and the date and time are set to the last recorded time that the system booted.

Note

HP recommends that you set the correct system time before allowing the system to run, so that all functions using time-stamping (such as the operator log, the error log, accounting records, file creation dates, and file expiration dates) contain correct time values.

Depending on the value specified for the TIMEPROMPTWAIT parameter, the system acts in one of the following ways:

TIMVCFAIL (D)

TIMVCFAIL specifies the time required for an adapter or virtual circuit failure to be detected. HP recommends that the default value be used. HP also recommends that this value be lowered only in OpenVMS Cluster of three CPUs or less, that the same value be used on each computer in the cluster, and that dedicated LAN segments be used for cluster I/O.

TMSCP_LOAD (A)

TMSCP_LOAD allows the loading of the tape mass storage control protocol server software. The TMSCP_LOAD parameter also sets locally connected tapes served. For information about setting the TMSCP_LOAD parameter, see HP OpenVMS Cluster Systems.

Setting TMSCP_LOAD to 0 inhibits the loading of the tape server and the serving of local tapes. Setting TMSCP to 1 loads the tape server into memory at the time the system is booted and makes all directly connected tape drives available clusterwide. The following table describes the two states of the TMSCP_LOAD parameter:
State Function
0 Do not load the TMSCP tape server. Do not serve any local tape devices clusterwide. This is the default value.
1 Load the TMSCP tape server. Serve all local TMSCP tape devices clusterwide.

TMSCP_SERVE_ALL

TMSCP_SERVE_ALL is a bit mask that controls the serving of tapes. The settings take effect when the system boots. You cannot change the settings when the system is running.


Previous Next Contents Index