z/VM New Function Variable List
Last Updated: 15 May 2025
The table below contains a listing of variables and associated data used for indicating z/VM new function. Mouse over the table headers for descriptions on the columns. The data can be sorted by clicking on the table headers, and data in the table can be filtered by using the text input field on the right.
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| Release | APAR | Name | Environment variable name | Data type | Variable value | Variable value description | Last updated |
|---|---|---|---|---|---|---|---|
| 7.4 | TBD | Improve Soft ABEND Control |
CP.FUNCTION.SOFTABEND TBD |
softonly limit | TBD | TBD | 20250515May 15, 2025 |
| TBD | TBD | Allow TRSOURCE to cause a SNAPDUMP |
CP.FUNCTION.TRSOURCE.SNAPDUMP Value indicates number of SNAPDUMPs produced by a trace point. |
snap value | 2 | Default value of the SNAP directive, which limits number of SNAPDUMPs produced by a trace point. | 20250515May 15, 2025 |
| 7.4 | VM66829 | MSS in TRSOURCE Support |
CP.FUNCTION.TRSOURCE.MSS This variable indicates what level of MSS in TRSOURCE Support is installed. |
support level | 1 | Support for Multiple Subchannel Sets (MSS) in TRSOURCE is installed on this system. | 20250403April 3, 2025 |
| 7.4 | VM66829 | Two-Speed Monitoring |
CP.LIMIT.MONITOR.SUBINTERVAL Value indicates, in seconds, the minimum subinterval that can be defined. |
sample interval | 1 | Subinterval collection is supported at a minimum granularity of one second. | 20250403April 3, 2025 |
| 7.4 | TBD | Root of Trust |
CP.FUNCTION.SECURITY.IPL This variable indicates what level of Secure IPL is installed. |
support level | 2 | Root of Trust is installed on this system. | 20240627June 27, 2024 |
| 7.3 | VM66758 | SCSI IPL Alternate Path Support |
CP.FUNCTION.SCSI.IPL.ALTERNATE_PATH This variable indicates that z/VM's SCSI IPL Alternate Path Support is available and if IPL fails using the primary path then an alternate path will be automatically used. |
support level | 2 | Relax SCSI alternate path definition restrictions to allow the same device number to be used with different port names. | 20240509May 9, 2024 |
| 7.3 | VM66758 | Query SCPID |
CP.FUNCTION.QUERY.SCPID This variable indicates whether QUERY SCPID function is available. |
support level | 1 | Version 1 of Query SCPID is available. | 20240429April 29, 2024 |
| 7.3 | VM66678 | Warning Track Interruption Facility |
CP.FUNCTION.SRM.WARNINGTRACK This variable indicates whether Warning Track support is available. |
support level | 1 | Version 1 of Warning Track support is available. | 20240429April 29, 2024 |
| 7.3 | VM66673 | Large Guest LOGOFF Reset Time Mitigation |
CP.FUNCTION.FAST_GUEST_LOGOFF Indicates that a guest is considered to be logged off before its virtual memory reset is complete, allowing it to be logged back on before the resources associated with its virtual memory are completely released. |
support level | 1 | Version 1 of large guest reset time mitigation is available. | 20231101November 1, 2023 |
| 7.3 | VM66727 | SCSI IPL Alternate Path Support |
CP.FUNCTION.SCSI.IPL.ALTERNATE_PATH This variable indicates that z/VM's SCSI IPL Alternate Path Support is available and if IPL fails using the primary path then an alternate path will be automatically used. |
support level | 1 | SCSI IPL Alternate Path Support is installed on this system. | 20231006October 6, 2023 |
| 7.3 | VM66423 | Crypto Stateless-Command Filtering |
CP.FUNCTION.CRYPTO.HW_CCA_FILTERING This variable indicates that z/VM's exploitation of the Crypto Stateless-Command Filtering facility available on CEX8C adapters will replace the crypto stateless-command filtering performed in z/VM for APVIRT crypto users. |
support level | 1 | Crypto Stateless-Command Filtering is installed on this system. | 20230404April 4, 2023 |
| 7.3 | VM66434 | Guest Secure-IPL |
CP.FUNCTION.SECURITY.IPL This variable indicates what level of Secure IPL is installed. |
support level | 1 | Guest Secure-IPL is installed on this system. | 20230404April 4, 2023 |
| 7.3 | VM66654 | Thin Stack Adapter Interrupt Support |
CP.FUNCTION.THINSTACK This variable indicates what level of Thin Stack Adapter Interrupt Support is installed. |
support level | 1 | Thin Stack Adapter Interrupt Support is installed on this system. | 20230317March 17, 2023 |
| 7.3 | VM66679 | VMEVENT Enhancements |
CP.FUNCTION.VMEVENT The variable is a decimal integer that specifies the version of *VMEVENT Ehancements support installed. |
support level | 1 |
A value of null means no additional *VMEVENTs defined. Only the events defined in z/VM Release 7.2 are supported. A value of 1 indicates the support level in effect for *VMEVENT enhancements and includes the following listed below.
|
20230216February 16, 2023 |
| 7.3 | VM66675 | Support Larger NVMe EDEVICE Page Space Allocations |
CP.FUNCTION.EDEVICE.NVME This variable indicates the level of NVMe EDEVICE support installed. |
support level | 2 | The variable is a decimal integer that specifies the version of NVMe EDEVICE support installed. Version 1 provides basic NVMe EDEVICE support; Version 2 adds support for large page space allocations. | 20230118January 1, 2023 |
| 7.3 | N/A | Display Mnemonics of Instructions Not Supported by CP TRACE |
CP.FUNCTION.TRACE.MNEMONICS Indicates that mnemonics for valid opcodes will be included in TRACE and DISPLAY output. |
support level | 1 | Display Mnemonics of Instructions Not Supported by CP TRACE is installed on this system. | 20220805August 5, 2022 |
| 7.3 | N/A | ESM Control of DEFINE MDISK Command |
CP.ESM.CONTROL.DEFINE.MDISK This variable indicates the presence of Control Program support for an External Security Manager to control the DEFINE MDISK command. |
support level | 1 | CP Support of ESM Control of the DEFINE MDISK command is installed. | 20220405April 5, 2022 |
| 7.3 | N/A | SSI 8-Member Clusters |
CP.LIMIT.SSI.MEMBERS The value of this variable represents the maximum number ofAmembers in a Single 7 System Image (SSI) cluster supported by this level of CP. |
decimal integer | 8 | The variable is a decimal integer with a value of 8. This means that the level of CP code on the system supports up to eight members in an SSI cluster when it is properly enabled. Prior to the existence of this variable, four members were supported. | 20220405April 5, 2022 |
| 7.3 | N/A | NVMe EDEVICE Support |
CP.FUNCTION.EDEVICE.NVME This variable indicates whether NVMe EDEVICE support is installed. |
support level | 1 | Version 1 of NVMe EDEVICE support is installed. | 20220405April 5, 2022 |
| 7.2 | VM66450 | Non Full-Pack Minidisk HPF I/O Support |
CP.FUNCTION.DASD.MINIDISK.HPF.PHASE Defines the level of guest High Performance FICON opcode support. |
support level | 1 | The value of the variable associated with this function is the support level, known as the "phase". | 20220401April 1, 2022 |
| 7.2 | VM66522 | Hipersockets Bridge Connectivity Loss on Shutdown |
CP.FUNCTION.VSWITCH.SHUTDOWN This variable indicates SHUTDOWN will terminate the network connections for the uplinks associated with Global VSwitches and any Bridge Ports. |
support level | 1 | Network termination support at SHUTDOWN is installed on this system. | 20220401April 1, 2022 |
| 7.2 | VM66449 | VARY ON RDEV Multi Processor Support |
CP.FUNCTION.DASD.MP_VARY_RDEV This variable indicates the presence of multi processor support for the VARY ON RDEV command. |
support level | 1 | The VARY ON RDEV command now has the ability to complete its processing using multiple threads running on multiple processors. This work previously was limited to running on only the master processor. This ability reduces the response time of large VARY ON RDEV commands. | 20211207December 7, 2021 |
| 7.2 | VM66479 | Spool Information Enhancements |
CP.FUNCTION.SPOOL.EXTENSIONS This variable indicates whether support for Spool Information Enhancements is installed. |
support level | 1 | Version 1 of Spool Information Enhancements is installed. | 20211013October 13, 2021 |
| 7.2 | VM66507 | EDEVICE Path Management |
CP.FUNCTION.EDEVICE.PATH_MANAGEMENT This variable indicates whether support for EDEVICE Path Management is installed. |
support level | 1 | Version 1 of EDEVICE Path Management is installed. | 20210831August 31, 2021 |
| 7.2 | VM66557 | VSwitch Bridge Port Enhancements |
CP.FUNCTION.VSWITCH.NICDISTRIBUTION This variable indicates the ability to configure the NICDistribution setting for a VSwitch BridgePort. |
support level | 1 | The NICDISTRIBUTION function for a VSWITCH BRIDGEPORT is installed on this system. | 20210812August 12, 2021 |
| 7.2 | VM66534 | Host Exploitation of Crypto Interruptions |
CP.FUNCTION.CRYPTO.INTERRUPTIONS This variable indicates whether support for Host Exploitation of Crypto Interruptions is installed. |
support level | 1 | Version 1 of Host Exploitation of Crypto Interruptions is installed. | 20210504May 4, 2021 |
| 7.2 | VM66496 | Mixed-APVIRT LGR |
CP.FUNCTION.CRYPTO.MIXED_APVIRT_LGR This variable indicates whether support for Improved Live Guest Relocation for Shared Crypto Users (aka LGR for Mixed APVIRT) is installed. |
support level | 1 | Version 1 of LGR for Mixed APVIRT is installed. | 20210420April 20, 2021 |
| 7.2 | VM66485 | IPV6 Layer 2 Query Support |
CP.FUNCTION.VSWITCH.IPV6QUERY This variable indicates that IPv6 addresses for Layer 2 VSwitches will be displayed on the QUERY VSWITCH and the QUERY VIRTUAL NIC commands and on the output of the DIAG '26C'. |
support level | 1 | IPV6 Layer 2 Query Support is installed. | 20210420April 20, 2021 |
| 7.2 | VM66173 | Dynamic Memory Downgrade |
CP.FUNCTION.MEMORY.RECLAIM This variable indicates the presence of functionality which allows real memory to be dynamically removed from a running CP system. |
support level | 1 | Dynamic removal of reconfigurable memory is supported. | 20210408April 8, 2021 |
| 7.2 | VM66271 | Dynamic Memory Downgrade |
CP.LIMIT.MEMORY.RECONFIG This variable indicates the current limitation on how much storage can be designated as reconfigurable. Reconfigurable memory may only be defined if there is already 4 GB of memory designated as permanent. |
decimal integer | 50 | Value indicates the maximum percentage of a system's real memory can be reconfigured. 0 = No reconfigurable memory. 50 = 50% of memory is designated as reconfigurable. |
20210408April 8, 2021 |
| 7.2 | VM66173 | Dynamic Memory Downgrade |
CP.LIMIT.MEMORY.RECONFIG This variable indicates the current limitation on how much storage can be designated as reconfigurable. Reconfigurable memory may only be defined if there is already 4 GB of memory designated as permanent. |
decimal integer | 0 | VM66173 introduces the new function variable. The variable value is initially fenced at 0 which means no reconfigurable memory. APAR VM66271 will remove the fence and allow the user to set the reconfigurable memory value up to 50. | 20210408April 8, 2021 |
| 7.2 | VM66173 | Four TB Main Memory Support |
CP.LIMIT.MEMORY.REAL_TOTAL This variable indicates the limitation on the maximum real memory supported for a z/VM system. The variable is a decimal integer value of terabytes of real memory. The amount of memory supported per guest or on a second level z/VM system may be different. See CP Planning and Administration for more details. |
Positive decimal integer | 4 | Variable value indicates that 4 TB is the maximum real memory supported for a z/VM system. | 20210408April 8, 2021 |
| 7.2 | VM66560 | Preserve Partial Dump Across IPL |
CP.FUNCTION.DUMP.PRESERVE_PARTIAL The variable indicates whether the support for preserving a partial dump across a re-IPL is present. |
support level | 1 | Preserve Partial Dump Across IPL is installed. | 20210127January 27, 2021 |
| 7.2 | VM66420 | EDEVICE Optional LUN Specification |
CP.FUNCTION.EDEVICE.DEFINITION This variable indicates enhancements to the SET EDEVICE command or the EDEVICE system configuration statement. |
support level | 1 | The LUN operand on the SET EDEVICE command and the EDEVICE system config statement is optional after the first path has been established. | 20201212December 12, 2020 |
| 7.2 | VM66421 | 1-END HyperPAV Minidisk Support |
CP.FUNCTION.DASD.HYPERPAV_1_END This variable indicates new Parallel Access Volume (PAV) function. |
support level | 1 | Support for 1-END HyperPAV Minidisks is available. | 20201212December 12, 2020 |
| 7.2 | VM66469 | CP QUERY DEVICES |
CP.FUNCTION.QUERY.DEVICES This variable indicates the ability to report real device settings established by the DEVICES configuration statement and the SET DEVICES command. |
support level | 1 | CP QUERY DEVICES function is installed. | 20201008October 8, 2020 |
| 7.2 | VM66431 | Improve I/O Time for Dump Processing |
CP.FUNCTION.DUMP.SPEEDUP This variable indicates the presence of functionality which reduces the elapsed time required to write CP dumps. |
support level | 1 | z/VM exploits the use of zHPF I/O to reduce the I/O elapsed time for writing hard abend and snap dumps. | 20200915September 15, 2020 |
| 7.2 | VM66201 | z/XC Architecture Support |
CP.FUNCTION.ZXC This variable indicates the presence of support for z/XC architecture mode, that is, the ability for XC virtual machines to exploit z/Architecture instruction set and capabilities concurrentlly with VM Data Spaces. |
support level | 1 | z/XC architecture mode is available for XC virtual machines. | 20200915September 15, 2020 |
| 7.2 | VM66433 | FlashCopy Preserve Mirror Support |
CP.FUNCTION.COPYSERVICES.FC_PRESERVE_MIRROR This variable indicates the presence of Preserve Mirror support for z/VM FlashCopy commands. |
support level | 1 | FlashCopy commands have the "PRESERVemirror" operand to be used to avoid PPRC suspend conditions when the target of a FlashCopy is also a PPRC Primary device. FlashCopy now also allows target devices to be Global Mirror Primary devices. | 20200914September 14, 2020 |
Data type indicates the number of SNAPDUMPs produced by a trace point.
Data type indicates that the variable is associated with support level. A variable value of one indicates the initial support. Each successive value represents an additional enhancement in the area described by the variable.
Data type indicates that the variable is associated with sample interval level. A variable value of one indicates the initial support of a one second minimum.