![]() |
HP OpenVMS systems documentation |
| Previous | Contents | Index |
This special parameter is used by HP and is subject to change. Do not change this parameter unless HP recommends that you do so.
Possible values are the following:
| Value | Explanation |
|---|---|
| NEVER | (Default) Never use the higher overhead option to improve fairness for any write-shared files accessed on the system; minimal overhead. |
| SOMETIMES | Use this option for fairer bucket access (but higher overhead) to any write-shared files with global buffers enabled that are accessed on the system. |
| ALWAYS | Use this option for fairer bucket access (but higher overhead) to all write-shared files accessed on the system. |
You can set this system parameter with the DCL command SET RMS_DEFAULT/SYSTEM/CONTENTION_POLICY=value and display the parameter with the DCL command SHOW RMS_DEFAULT.
You can set this system parameter with the DCL command SET RMS_DEFAULT/SYSTEM and display the parameter with the SHOW RMS_DEFAULT command.
You can set this system parameter with the DCL command SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_DEFAULT.
You can set this system parameter with the DCL command SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_DEFAULT.
The default value is usually adequate. However, if read-ahead or write-behind operations are used, a larger number improves performance.
You can set this system parameter with the DCL command SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_DEFAULT.
You can set this system parameter with the DCL command SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_DEFAULT.
You can set this system parameter with the DCL command SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_DEFAULT.
The network block count value represents the number of blocks that RMS is prepared to allocate for the I/O buffers used to transmit and receive data. The buffer size used for remote file access, however, is the result of a negotiation between RMS and the remote file access listener (FAL). The buffer size chosen is the smaller of the two sizes presented.
Thus, RMS_DFNBC places an upper limit on the network buffer size that is used. It also places an upper limit on the largest record that can be transferred to or from a remote file. In other words, the largest record that can be transferred must be less than or equal to RMS_DFNBC multiplied by 512 bytes.
You can set this system parameter with the DCL command SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_DEFAULT.
When small disk quotas are used, specify a small number such as the disk cluster size to prevent the user's disk quota from being consumed. If the value of 0 is used, RMS allocates large extents and truncates the file back to its actual usage when it closes.
You can set this system parameter with the DCL command SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_DEFAULT.
Because a process always inherits its default file protection from its creator process, RMS_FILEPROT determines default file protection only for users who do not execute the DCL command SET PROTECTION/DEFAULT in their login command procedures or during interactive sessions.
The protection is expressed as a mask. (See the discussion of the $CRMPSC system service in the HP OpenVMS System Services Reference Manual for more information about specifying protection masks.) By default, the mask is 64000 (decimal) or FA00 (hexadecimal), which represents the following protection:
|
(S:RWED,O:RWED,G:RE,W:) |
| Setting | Description |
|---|---|
| 0 (default) | Do not enable writebehind feature. Preserve prior behavior of using writebehind only if the user requests it by setting RAB$V_WBH in RAB$L_ROP. |
| 1 | Enable writebehind feature as system default, including the allocation of at least two local buffers. |
On VAX systems, RSRVPAGCNT sets the number of pages that are reserved and escrowed for the current process page file.
This special parameter is used by HP and is subject to change. Do not change this parameter unless HP recommends that you do so.
This special parameter is used by HP and is subject to change. Do not change this parameter unless HP recommends that you do so.
| Bit | Set or Clear | Meaning |
|---|---|---|
| 0 | Clear | Traditional scheduling algorithm |
| Set | New 1-CPU release scheduling algorithm | |
| 1 | Set | No process will be scheduled on the primary CPU. |
Beginning in OpenVMS Version 7.3-1, the default value for SCH_CTLFLAGS is 1.
On Alpha and I64 systems, the system communication services (SCS) buffers are allocated as needed, and SCSBUFFCNT is reserved for HP use only.
The default value is adequate on most systems. If a systems communication architecture (SCA) port is not configured on your system, this parameter is ignored.
The purpose of SCSI_ERROR_POLL is to cause OpenVMS to send a SCSI Test Unit Ready command every hour to each SCSI disk, in an attempt to force latched errors to become unlatched and to be reported immediately. SCSI_ERROR_POLL has a default value of 1. It can, however, be set to 0 by the user in order to stop the error polling activity.
The parameter affects SCSI disks connected by Fibre Channel as well as parallel SCSI. If the disk has multiple paths, then the error polling is performed on all non-served paths to the disk. Tapes and other non-disk devices are not subject to this error polling, regardless of the parameter setting.
SCSI_NOAUTO prevents the loading of a disk or tape SCSI class driver for any given device ID in a configuration that includes a SCSI third-party device. The SCSI_NOAUTO system parameter stores a bit mask of 32 bits, where the low-order byte corresponds to the first SCSI bus (PKA0), the second byte corresponds to the second SCSI bus (PKB0), and so on, as follows:
For each SCSI bus, setting the low-order bit inhibits automatic configuration of the device with SCSI device ID 0; setting the second low-order bit inhibits automatic configuration of the device with SCSI device ID 1, and so forth. For instance, the value 00002000_16 prevents the device with SCSI ID 5 on the bus identified by SCSI port ID B from being configured. By default, all the bits in the mask are cleared, allowing all devices to be configured.
This special parameter is used by HP and is subject to change. Do not change this parameter unless HP recommends that you do so.
Specify SCSNODE as a string of up to six characters. Enclose the string in quotation marks.
The maximum size of six characters is strictly enforced. SYSBOOT truncates the value of SCSNODE if the size of the system parameter is set to more than six characters. |
If the computer is in an OpenVMS Cluster, specify a value that is unique within the cluster. Do not specify the null string.
If the computer is running DECnet for OpenVMS, the value must be the same as the DECnet node name.
If SCA or DSA ports are not configured on your system, the system ignores SCSRESPCNT.
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:
SCSSYSTEMID = ((DECnet area number) * 1024) + (DECnet node number) |
Example: If the DECnet address is 2.211, calculate the value as follows:
SCSSYSTEMID = (2 * 1024) + 211 = 2259 |
The following bits are defined:
| Bit | Description |
|---|---|
| 0 | Obsolete. |
| 1 | Allows multiple user names to connect to DECW$SERVER. |
| 2 | Allows unevaluated DECwindows transports (such as TCP/IP). |
| 3 | Allows $SIGPRC and $PRCTERM to span job trees. |
| 4 | Allows security profile changes to protected objects on a local node when the object server is absent and cannot update the cluster database VMS$OBJECTS.DAT. |
| 5 | Allows creation of protected objects on a local node when the object server is absent and cannot update the cluster database VMS$OBJECTS.DAT. |
| 6 | Allows SPAWN or LIB$SPAWN commands in CAPTIVE accounts. |
| 7 | Reserved to HP. |
| 8 | Reserved to HP. |
| 9 | Disables password synchronizations among ACME agents on a systemwide pasis. This is functionally equivalent to the SYS$SINGLE_SIGNON logical name bit mask value 4 for LOGINOUT. |
| 10 |
Allows privileged applications to successfully authenticate a user
whose principal name maps to a SYSUAF record that is either expired or
whose modal restrictions would otherwise prevent the account from being
used.
A SYSUAF record that is disabled or password-expired (in the case of traditional OpenVMS authentication) cannot be bypassed in this manner. An application with SECURITY privilege specifies the SYS$ACM ACME$M_NOAUTHORIZE function modifier to override authorization checks. |
| 11 | Allows any record in the SYSUAF file to be mapped using external authentication. |
| 12 | Allows intrusions on a clusterwide or local basis. (If the bit is cleared, intrusions are clusterwide.) |
The default value of 7 preserves compatibility with existing DECwindows Motif behavior. A value of 0 disables all unevaluated configurations.
SHADOW_PSM_DLY 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_DLY is used as the default shadow set member recovery delay for that shadow set. To modify SHADOW_PSM_DLY for an existing shadow set, refer to the $SET SHADOW/ /RECOVERY_OPTIONS=DELAY_PER_SERVED_MEMBER=n command.
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. |
The reset threshold is specified by the RESET_THRESHOLD keyword in the /POLICY qualifier of the SET SHADOW command. This comparison is performed for all shadow sets mounted on the system that have HBMM bitmaps.
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 the setting of
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.
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 I64 systems, the default value for this system parameter is 500, which consumes 24KB of main memory. On OpenVMS VAX systems, the default value is 100, which consumes 5KB 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 23.5KB of main memory on an OpenVMS Alpha or I64 system and 4.5KB 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.
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_REC_DLY can be used to better predict which systems in an OpenVMS Cluster will perform 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 the remaining systems.
The range of SHADOW_REC_DLY is 0 to 65535 seconds. The default value is 20 seconds.
For more information about controlling which systems perform the merge or copy operations, refer to HP Volume Shadowing for OpenVMS.
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.
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.
To enable minimerge on a system disk, 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. Also, be sure to set the DUMPSTYLE parameter to dump off system disk, as described in the HP OpenVMS System Manager's Manual.
| Previous | Next | Contents | Index |