HP OpenVMS Systems Documentation
HP OpenVMS System Management Utilities Reference Manual
SCSSYSTEMID (G)Specifies a number that identifies the computer. This parameter is not dynamic. SCSSYSTEMID is the low-order 32 bits of the 48-bit system identification number.
If the computer is in an OpenVMS Cluster, specify a value that is unique within the cluster. Do not use zero as the value.
If the computer is running DECnet for OpenVMS, calculate the value from the DECnet address using the following formula:
Example: If the DECnet address is 2.211, calculate the value as follows:
SCSSYSTEMIDH (G)Specifies the high-order 16 bits of the 48-bit system identification number. This parameter must be set to 0. It is reserved by HP for future use.
SECURITY_POLICYSECURITY_POLICY allows a system to run in a C2 or B1 configuration and to subset out particular pieces of functionality---to exclude functionality that is outside the evaluated configuration or to preserve compatibility with previous versions of the operating system. See the HP OpenVMS Guide to System Security for further information about the C2 and B1 evaluated configurations.
The following bits are defined:
SETTIMESETTIME 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_ENABLESpecial parameter reserved for HP use.
SHADOWINGSHADOWING 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:
SHADOW_HBMM_RTC (D)(Alpha and I64) 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.
SHADOW_MAX_UNITSHADOW_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.
On Alpha and I64 systems, the default value for this system parameter is 500, which consumes 24 KB of main memory. On OpenVMS VAX systems, the default value is 100, which consumes 5 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 I64 system and 4.5 KB of main memory on a VAX system. (The maximum value of this parameter is 10,000.)
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.
SHADOW_PSM_RDLYWhen 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 I64)
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 I64) 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_DISKA 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_TMOThe 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_UNITUse 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_WAITThe 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:
SMCI_PORTSOn 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_BITMAPThis 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:
The command in this example sets bits 0, 5, 17, 18, 19, 20, and 21 in the bitmap and clears all other bits.
SMP_SANITY_CNTSMP_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.
SMP_SPINWAITSMP_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.
SMP_TICK_CNTSMP_TICK_CNT sets the frequency of sanity timer checks by each CPU in a multiprocessing system.
SPTREQ (A)(VAX only) SPTREQ sets the number of system page table (SPT) entries required for mapping the following components:
SSINHIBITSSINHIBIT controls whether system services are inhibited (1) (on a per-process basis). By default, system services are not inhibited (0).
STARTUP_P1--8The following table describes possible values of STARTUP_P1 through _P8:
SWP_PRIOSWP_PRIO sets the priority of I/O transfers initiated by the swapper.
SWPALLOCINC(VAX only) SWPALLOCINC sets the size (in blocks) to use to back up swap file space allocation in the swap or page file. Space in the file is allocated in multiples of this unit (up to WSQUOTA) to guarantee swap space.
SWPFAILSWPFAIL sets the number of consecutive swap failures allowed before the swap schedule algorithm is changed to ignore the swap quantum protection.
SWPFILCNTOn VAX systems, SWPFILCNT defines the maximum number of swap files that can be installed.
SWPOUTPGCNT (A on VAX,D)This parameter allows the swapper an alternative mechanism before actually performing swaps.
On VAX systems, SWPOUTPGCNT defines the minimum number of pages to which the swapper should attempt to reduce a process before swapping it out. The pages taken from the process are placed into the free-page list.
On Alpha and I64 systems, 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.
SWPRATESWPRATE sets the swapping rate (in 10-millisecond units). This parameter limits the amount of disk bandwidth consumed by swapping.
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.
SYSPFCSYSPFC sets the number of pages to be read from disk on each system paging operation.
SYSSER_LOGGING (D)(Alpha and I64) A value of 1 for SYSSER_LOGGING enables logging of system service requests for a process. The default is 1.
SYSTEM_CHECKSYSTEM_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):
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.