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Performance Management

These changes affect the performance management of z/VM:

• Monitor Changes
• Command and Output Changes
• Effects on Accounting and Performance Data
• Performance Toolkit for VM Changes

Monitor Changes

There were several changes and areas of enhancements affecting the CP monitor data for z/VM 5.3 involving system configuration information and additional data collection. As a result of these changes, there are twelve new monitor records, a new monitor domain, and several changed records. The detailed monitor record layouts are found on our control blocks page.

In z/VM 5.3, support is provided for virtual CPU types of zAAP (IBM System z Application Assist Processor), zIIP (IBM System z9 Integrated Information Processor), and IFL (Integrated Facility for Linux), in addition to general-purpose CPs (Central Processors). To assist in monitoring these specialty engines two new monitor records, Domain 0 Record 24 (Scheduler Activity (per processor type)) and Domain 2 Record 12 (SET CPUAFFINITY Changes) have been added. In addition, the following monitor records have been updated to specify the processor type:

In z/VM 5.3, CP can support up to 32 real processors in a single z/VM image. As a result, the scheduler lock has been changed from an exclusive spin lock to a shared/exclusive spin lock to help reduce scheduler lock contention. To assist in debugging spin lock contention problems, the Domain 0 Record 23 (Formal Spin Lock Data (Global)) record has been added to Monitor along with updates to the Domain 0 Record 10 (Scheduler Activity (Global)) record, the Domain 0 Record 13 (Scheduler Activity (per processor)) record, and the Domain 4 Record 3 (User Activity Data) record.

Support was added in z/VM 5.2 to exploit large real memory by allowing use of memory locations above the 2G address line, thus helping to reduce the constraints on storage below the 2G address line. The constraints on storage below the 2G address line are further reduced in z/VM 5.3 by moving the page management blocks (PGMBKs) above 2G. In addition, CP has been enhanced to improve the management of contiguous frames of host real storage. These changes resulted in updates to the Domain 0 Record 3 (Real Storage Data (Global)), Domain 3 Record 1 (Real Storage Management (Global)), Domain 3 Record 2 (Real Storage Activity (Per Processor)), and Domain 3 Record 3 (User Activity Data) records.

The Hyper Parallel Access Volume (HyperPAV) function, optionally provided by the the IBM System Storage DS8000 disk storage systems, is now supported in z/VM 5.3. z/VM provides support of HyperPAV volumes as linkable minidisks for guest operating systems, such as z/OS, that exploit the HyperPAV architecture. This support is also designed to transparently provide the potential benefits of HyperPAV volumes for minidisks owned or shared by guests that do not specifically exploit HyperPAV volumes, such as Linux and CMS. To allow for monitoring of the HyperPAV support, four new monitor records are added: Domain 1 Record 20 (HyperPAV Pool Definition), Domain 6 Record 28 (HyperPAV Pool Activity), Domain 6 Record 29 (HyperPAV Pool Creation), and Domain 6 Record 30 (LSS PAV Transition). Also, the following records are enhanced: Domain 1 Record 6 (Device Configuration Data), Domain 6 Record 1 (Vary On Device - Event Data), Domain 6 Record 3 (Device Activity), and Domain 6 Record 20 (State Change).

A new monitor domain, Domain 8 - Virtual Network Domain, has been added to control and record monitor activity for virtual network resources. Monitoring of virtual networks is not enabled automatically using the CP MONITOR START command. The CP MONITOR SAMPLE ENABLE command with either the ALL or NETwork options must be issued to signal collection of virtual network sample data and the CP MONITOR EVENT DISABLE command with either the ALL or NETwork options must be issued to end the collection of virtual network event data. There are currently three new records in this domain: Domain 8 Record 1 (Virtual NIC Session Activity), Domain 8 Record 2 (Virtual Network Guest Link State Change - Link Up), and Domain 8 Record 3 (Virtual Network Guest Link State Change - Link Down).

A Simple Network Management Protocol (SNMP) agent is provided in z/VM 5.3 to perform information management functions, such as gathering and maintaining performance information and formatting and passing this data to the client when requested. This information is collectively called the Management Information Base (MIB) and is captured in the Domain 6 Record 21 (Virtual Switch Activity), Domain 6 Record 22 (Virtual Switch Failover), and Domain 6 Record 23 (Virtual Switch Recovery) records. In addition, the MIB data is used in the new Domain 8 Record 2 (Virtual Network Guest Link State Change - Link Up) record and the Domain 8 Record 3 (Virtual Network Guest Link State Change - Link Down) record.

In z/VM 5.3 the Virtual Switch, configured for Ethernet frames (layer 2 mode), now supports aggregating of 1 to 8 OSA-Express 2 adapters with a switch that supports the IEEE 802.3ad Link Aggregation specification. The following records are updated to contain link aggregation monitor information: Domain 6 Record 21 (Virtual Switch Activity), Domain 6 Record 22 (Virtual Switch Failover), and Domain 6 Record 23 (Virtual Switch Recovery). Also, the new Domain 8 Record 1 (Virtual Network NIC Session Activity) record contains this information as well.

Lastly, two new monitor records -- Domain 5 Record 11 (Instruction Counts (Per Processor)) and Domain 5 Record 12 (Diagnose Counts (Per Processor)) -- have been added to provide additional debug information for system and performance problems.

Command and Output Changes

The CP MONWRITE utility has been updated in z/VM 5.3 to allow for better management of monitor data (MONDATA) files. A new CLOSE option was added to allow a MONDATA file to automatically be closed, saved to disk, and a new file opened at an interval specified by the user. Addtionally, the user can specify the name of a CMS EXEC file that will be called once the current MONDATA file is closed, allowing for the manipulation or cleanup of existing MONDATA files.

Previous to z/VM 5.3, on systems with a large number of devices defined, CP MONITOR data records would sometimes be missing for some of the devices. This often occurred because the MONITOR SAMPLE CONFIG SIZE was too small. In z/VM 5.3, when using the MONWRITE utility, a new message: HCPMOW6273A - WARNING: SAMPLE CONFIGURATION SIZE TOO SMALL is now issued when the connection to MONITOR is made indicating this condition. To increase the size of the SAMPLE CONFIGURATION area, use the CP MONITOR SAMPLE CONFIG SIZE option.

For information on the CP MONWRITE Utility, see the CP Commands and Utilities Reference.

Effects on Accounting and Performance Data

Accounting support has been added for specialty engines. Two new fields (Virtual CPU type code and Real CPU type code) have been added to the Type 1 accounting records that are cut for each virtual CPU that is defined in each virtual machine. A new field (Secondary CPU capability) was added to the Type D accounting record so as to cover the case where a specialty engine runs at a different speed from normal processors. Finally, the ACCOUNT utility has been updated to include two new options (VCPU and RCPU) that can be used to limit its processing of Type 1 accounting records to those that match the specified virtual or real CPU type.

See chapter 8 in CP Planning and Administration for further information on the accounting record changes and chapter 3 in CMS Commands and Utilities Reference for further information on the ACCOUNT utility.

In z/VM 5.2.0, CP time was charged to the VM TCP/IP controller while handling real OSA port communications. In z/VM 5.3.0, VSwitch was changed to handle the OSA port communications under SYSTEMMP. This time will now be reported under System time in Performance Toolkit reports. SYSTEMMP is more efficient, resulting in less CPU time per transaction than was seen with z/VM 5.2.0.

Performance Toolkit for VM Changes

Performance Toolkit for VM has been enhanced in z/VM 5.3 to include the following new reports:

Performance Toolkit for VM: New Reports

In addition, a number of existing reports have been updated as part of the support for specialty engines. The CPU, LPAR, LPARLOG, and PROCLOG reports were updated to include the CPU type. The LPAR report was updated to include a table showing information for all physical processors in the total system configuration, broken down by CPU type. The SYSCONF report was updated to show the number and status of all processors in the LPAR configuration, broken down by CPU type. See Specialty Engine Support for example reports and discussion of their use.

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