Many of the performance terms use postscripts to reflect the sources
of the data described in this document. In all cases, the terms
presented here are taken directly as written in the text to allow them
to be found quickly. Often there will be multiple definitions of the
same data field, differing only in the postscript. This allows the
precise definition of each data field in terms of its origins. The
postscripts are:
<none>
| No postscript indicates that the data are obtained from the VM/ESA
Realtime Monitor.
|
(C)
| Denotes data from the VSE console timestamps.
|
(H)
| Denotes data from the internal processor
instrumentation tools.
|
(I)
| Denotes data from the CP INDICATE USER command.
|
(Q)
| Denotes data from the SFS QUERY FILEPOOL STATUS command.
|
(QT)
| Denotes data from the CP QUERY TIME command.
|
Server
| Indicates that the data are for specific virtual machines,
(for example SFS, CRR, or VTAM/VSCS).
If there is more than one virtual machine of the same
type, these data fields are for all the virtual machines of that type.
|
(S)
| Identifies OS/2 data from the licensed program, System Performance
Monitor 2 (SPM2).
|
(T)
| Identifies data from the licensed program, Teleprocessing Network
Simulator (TPNS).
|
(V)
| Denotes data from the licensed program VM Performance
Reporting Facility.
|
Absolute Share
| An ABSOLUTE share allocates to a virtual machine an absolute
percentage of all the available system resources.
|
AVG FIRST (T)
| The average response time in seconds for the first reply that returns
to the screen.
For non-fullscreen commands
this is the command reflect on the screen.
|
AVG LAST (T)
| The average response time
in seconds
for the last response to the screen.
|
AVG THINK (T)
|
The average think time determined by TPNS for
all users.
|
Bactrian
| A two-humped curve used to represent the think times for both active
users and users who are logged on but inactive. The distribution
includes those long think times that occur when a user is not actively
issuing commands. Actual user data were collected and used as input to
the creation of the Bactrian distribution.
|
BFS
| Byte File System
|
CMS BLOCKSIZE
| The block size, in bytes, of the users' CMS minidisks.
|
Command
| In the context of reporting performance results, any user
interaction with the system being measured.
|
CP
| Control Program. The hypervisor component of VM.
|
CP/CMD
| For the FS7F, FS8F, and VSECICS workloads, this is the average
amount of
CP processor time used per command in milliseconds. For the PACE
workload, this is the average CP processor time per job in seconds.
|
CP/CMD (H)
| See CP/CMD. This is the hardware based measure.
|
CP CPU/CMD (V) Server
| CP processor time, in milliseconds,
run in the designated server machine per command.
|
CPU PCT BUSY (V)
| CPU Percent Busy.
The percentage of total available processor time used by the designated
virtual machine. Total available processor time is the sum of online
time for all processors and represents total processor capacity (not
processor usage).
|
CPU SECONDS (V)
| Total CPU time, in seconds, used by a given virtual machine.
|
CPU UTIL (V)
| The percentage of time a given virtual machine spends using
the CPU.
|
DASD IO/CMD (V)
| The number of real SSCH or RSCH instructions issued to DASD, per
job, used by the VSE guest in a PACE measurement.
|
DASD IO RATE (V)
| The number of real SSCH or RSCH instructions per second that are
issued to DASD on behalf of a given virtual machine.
For PACE measurements, the number of real SSCH or RSCH
instructions per second issued to DASD on behalf of the VSE guest.
|
DASD IO TOTAL (V)
| The number of real SSCH or RSCH instructions issued to DASD used by
the VSE guest in a PACE measurement.
|
DASD PAGE RATE (V)
| The number of DASD page reads per second plus DASD page writes
per second that occur in a given virtual machine.
|
DASD RESP TIME (V)
| Average DASD response time in milliseconds. This includes DASD
service time plus (except for page and spool volumes) any time the
I/O request is queued in the host until the requested device becomes
available.
|
DIAGNOSE
| An instruction that is used to request CP services by a virtual
machine. This instruction causes a SIE interception and returns control
to CP.
|
DIAG/CMD
| The total number of DIAGNOSE instructions used per command or job.
|
DISPATCH LIST
| The average over time of the number of virtual machines (including
loading virtual machines) in any of
the dispatch list queues (Q0, Q1, Q2 and Q3).
|
DPA
| Dynamic Paging Area. The area of real storage used by CP to
hold virtual machine pages, pageable CP modules and control blocks.
|
EDF
| Enhanced Disk Format. This refers to the CMS minidisk file system.
|
Elapsed Time (C)
| The total time, in seconds, required to execute the PACE batch
workload.
This is calculated using the timestamps that appear on the
console of the VSE/ESA guest virtual machine. The time the first
job started is subtracted from the time the last job ended.
|
ELIGIBLE LIST
| The average over time of the number of virtual machines (including
loading virtual machines) in any of
the eligible list queues (E0, E1, E2 and E3).
|
EMUL ITR
| Emulation Internal Throughput Rate.
The average number of transactions completed per second of emulation time.
This is from the EM_ITR field under TOTALITR of the RTM TRANSACT screen.
|
EMUL/CMD
| For the FS7F, FS8F, and VSECICS workloads, this is the
amount of processor time spent in emulation mode per command in
milliseconds. For the PACE workload, this is the emulation processor
time per job in seconds.
|
EMUL/CMD (H)
| See EMUL/CMD. This is the hardware based measurement.
|
ETR
| External Throughput Rate.
|
ETR (C)
| See ETR. The external throughput rate for the VSE guest measurements.
|
ETR (T)
| See ETR. TPNS-based calculation of ETR.
|
ETR RATIO
| This is the ratio of the RTM-based ETR calculation
and the
TPNS-based ETR calculation.
|
External TPNS
| The TPNS workload driver is run on a different system that is
connected to the measured system with a communications link. See
Internal TPNS.
|
FAST CLR/CMD
| The number of fast path clears of real storage per command or job.
This includes V=R and regular guests.
|
FCON/ESA
| FCON/ESA is a program that is available from IBM that provides
performance monitoring capabilities with system console operation in
full screen mode. FCON/ESA can provide an immediate view of system
performance or post process its own history files or VM/ESA monitor
data for selected data. Threshold monitoring and user loop
detection is provided. FCON/ESA also has the ability to monitor
remote systems.
|
FREE TOTL/CMD
| The number of requests for free storage per command or job.
This includes V=R and regular guests.
|
FREE UTIL
| The proportion of the amount of available free storage actually
used.
|
FREEPGS
| The total number of pages used for FREE storage (CP control blocks).
|
FST
| File Status Table. The CMS control block that contains
information about a file belonging to a minidisk or SFS directory.
|
GB
| Gigabytes. 1024 megabytes.
|
GUEST SETTING
| This field represents the type of VSE guest virtual machine in
a PACE measurement. This fields possible values are V=V, V=F or
V=R.
|
GUESTWT/CMD
| The number of entries into guest enabled wait state per job.
|
GUESTWT/SEC
| The number of entries into guest enabled wait state per second.
|
Hardware Instrumentation
| See Processor Instrumentation
|
IML MODE
| This is the hardware IML mode used in VSE guest measurements. The
possible values for this field are 370, ESA, or LPAR.
|
Instruction Path Length
| The number of machine instructions used to run a given
command, function or piece of code.
|
Internal Response Time
| The response time as seen by CP. This does not include line or
terminal delays.
|
Internal TPNS
| The TPNS workload driver is run as one or more virtual machines
in the system being measured. When used with TCP/IP, the loopback
IP address is used to direct communications between the TPNS and
TCP/IP stack virtual machine(s), thus eliminating the need for physical
communications hardware. See External TPNS.
|
ISFC
| Inter-System Facility for Communications
|
ITR
| Internal Throughput Rate. This is the number of units of work
accomplished per unit of processor busy time in an nonconstrained environment.
For the FS7F, FS8F, and VSECICS workloads this is represented as commands per
processor second. For the PACE workload, this is represented as jobs per
processor minute.
|
ITR (H)
| See ITR. This is the hardware based measure. In this case, ITR is
measured in external commands per unit of processor busy time. For the
FS7F, FS8F, and VSECICS workloads this is represented as commands per processor
second, while for the PACE workload this is represented in jobs per
processor minute.
|
ITR (V)
| See ITR. This is the VMPRF-based measure. ITR is
measured in external commands per unit of processor busy time.
|
ITRR
| Internal Throughput Rate Ratio. This is the RTM based ITR
normalized to
a specific run.
|
ITRR (H)
| See ITRR. This is the ITR (H)
normalized to a specific run.
|
ITRR (V)
| See ITRR. This is the ITR (V)
normalized to a specific run.
|
IUCV
| Inter-User Communication Vehicle. A VM generalized CP interface
that helps the transfer of messages either among virtual machines or
between CP and a virtual machine.
|
k
| Multiple of 1000.
|
Kb
| Kilobits. One kilobit is 1024 bits.
|
KB
| Kilobytes. One kilobyte is 1024 bytes.
|
MASTER CP (H)
| Total host (CP) state utilization for the master processor.
This is calculated as MASTER TOTAL (H) - MASTER EMUL (H).
|
MASTER CP
| Total CP processor utilization for the master processor.
This is calculated as MASTER TOTAL - MASTER EMUL.
|
MASTER EMUL
| Total emulation state utilization for the master processor.
For uniprocessors
this is the same as
'TOTAL EMUL'
and is generally not shown.
|
MASTER EMUL (H)
| Total emulation state utilization for the master processor.
For uniprocessors
this is the same as
'TOTAL EMUL'
and is generally not shown.
This is the hardware based calculation.
|
MASTER TOTAL
| Total utilization of the master processor. For uniprocessor
this is the same as
'TOTAL'
and is generally not shown.
|
MASTER TOTAL (H)
| Total utilization of the master processor. For uniprocessor
this is the same as
'TOTAL (H)'
and is generally not shown.
This is the hardware based calculation.
|
MB
| Megabytes. One megabyte is 1,048,576 bytes.
|
MDC AVOID
| The number of DASD read I/Os per second that were
avoided through the use of minidisk caching.
|
MDC HIT RATIO
| Minidisk Cache Hit Ratio.
|
MDC MODS
| Minidisk Cache Modifications.
The number of times per second
blocks were written in the cache, excluding
the writes that occurred as a result of minidisk cache misses.
This measure only applies to VM releases prior to VM/ESA 1.2.2.
|
MDC READS (blks)
| Minidisk Cache Reads.
The number of times per second
blocks were found in the cache as the result of
a read operation.
This measure only applies to VM releases prior to VM/ESA 1.2.2.
|
MDC READS (I/Os)
| Minidisk Cache Reads.
The total number of virtual read I/Os per second that read data from
the minidisk cache. This measure does not apply to VM releases
prior to VM/ESA 1.2.2.
|
MDC REAL SIZE (MB)
| The size, in megabytes, of the minidisk cache in real storage.
This measure does not apply to VM releases
prior to VM/ESA 1.2.2.
|
MDC WRITES (blks)
| Minidisk Cache Writes.
The number of CMS Blocks moved per second
from main storage to expanded storage.
This measure only applies to VM releases prior to VM/ESA 1.2.2.
|
MDC WRITES (I/Os)
| Minidisk Cache Writes.
The total number of virtual write I/Os per second that write data into
the minidisk cache. This measure does not apply to VM releases
prior to VM/ESA 1.2.2.
|
MDC XSTOR SIZE (MB)
| The size, in megabytes, of the minidisk cache in expanded storage.
|
Millisecond
| One one-thousandth of a second.
|
Minidisk Caching
| Refers to a CP facility that uses a portion of storage as a read
cache of DASD blocks. It is used to help eliminate I/O bottlenecks
and improve system response time by reducing the number of DASD read
I/Os. Prior to VM/ESA 1.2.2, the minidisk cache could only reside in
expanded storage and only applied to 4KB-formatted CMS minidisks
accessed via diagnose or *BLOCKIO interfaces. Minidisk caching was
redesigned in VM/ESA 1.2.2 to remove these restrictions. With VM/ESA 1.2.2,
the minidisk cache can reside in real and/or expanded storage and
the minidisk can be in any format. In addition to the diagnose and
*BLOCKIO interfaces, minidisk caching now also applies to DASD accesses
that are done using SSCH, SIO, or SIOF.
|
Minidisk File Cache
| A buffer used by CMS when a file is read or written to sequentially.
When a file is read sequentially, CMS
reads ahead as many blocks as will fit into the cache. When a file
is written sequentially, completed blocks are accumulated until
the cache is filled and then are written out together.
|
ms
| Millisecond.
|
Native
| Refers to the case where an operating system is run directly on
the hardware as opposed to being run as a guest on VM.
|
Non-shared Storage
| The portion of a virtual machine's storage that is
unique to that virtual machine, (as opposed to shared storage such
as a saved segment that is shared among virtual machines). This
is usually represented in pages.
|
NONPAGE RIO/CMD (V)
| The number of real SSCH and RSCH instructions issued per command
for purposes other than paging.
|
NONTRIV INT
| Non-trivial Internal response time in seconds. The
average response time for transactions that completed with more than
one drop from Q1 or one or more drops from Q0, Q2, or Q3 per second.
|
Non-Spool I/Os (I)
| Non-spool I/Os done by a given virtual machine.
This is calculated from INDICATE USER data obtained before and after
the activity being measured. The value shown is final IO - initial IO.
|
NPDS
| No Page Data-Set. A VSE/ESA option, when running on VM/ESA as a V=V
guest, that eliminates paging by VSE/ESA for improved efficiency. All
paging is done by VM/ESA.
|
NUCLEUS SIZE (V)
| The resident CP nucleus size in kilobytes.
This is from the <K bytes> column on the
Total Resident Nucleus line in the VMPRF System
Configuration Report.
|
OSA
| IBM S/390 Open Systems Adapter. An integrated S/390 hardware feature
that provides an S/390 system with direct access to Token Ring, Ethernet,
and FDDI local area networks.
|
PAGE/CMD
| The number of pages moved between real storage and DASD per
command or job.
|
PAGE IO RATE (V)
| The number of real SSCH or RSCH instructions issued on behalf of
system paging.
|
PAGE IO/CMD (V)
| The number of real SSCH and RSCH instructions issued per command on
behalf of system paging.
|
Path length
| See Instruction Path Length
|
PBT/CMD
| For the FS7F, FS8F, and VSECICS workloads,
this is the number of milliseconds of processor
activity per command. For the PACE workload, this is the number
of seconds of processor activity per job.
|
PBT/CMD (H)
| See PBT/CMD. This is the hardware based measure.
|
PCI
| Program controlled interrupt.
|
PERCENT CP (H)
| The percentage of all CPU time that is used by CP.
This is calculated as CP/CMD (H) / PBT/CMD (H).
|
PGBLPGS
| The number of system pageable pages available.
|
PGBLPGS/USER
| The number of system pageable pages available per user.
|
Privileged Operation
|
Any instruction that must be run in supervisor state.
|
PRIVOP/CMD
| The number of virtual machine privileged instructions simulated
per command or job.
This does not include DIAGNOSE instructions.
|
PRIVOPS (Privileged Operations)
| See Privileged Operation.
|
Processor Instrumentation
| An IBM internal tool used to obtain
hardware-related data such as processor utilizations.
|
Processor Utilization
| The percent of time that a processor is not idle.
|
Processors
| The data field denoting the number of processors that
were active during a measurement.
|
QUICKDSP ON
| When a virtual machine is assigned this option, it bypasses the normal
scheduler algorithm and is placed on the dispatch list immediately when it
has work to do. It does not spend time in the eligible lists.
QUICKDSP can be specified either via a CP command or in the CP directory
entry.
|
RAID
| Redundant array of independent DASD.
|
RAMAC
| A family of IBM storage products based on RAID technology. These
include the RAMAC Array Subsystem and the RAMAC Array DASD.
|
READS/SEC
| The number of pages read per second done for system paging.
|
Real Storage
| The amount of real storage (central storage)
used for a particular measurement.
|
Relative Share
| A relative share allocates to a virtual machine a portion of the
total system resources minus those resources allocated to virtual
machines with an ABSOLUTE share. A virtual machine with a RELATIVE
share receives access to system resources that is proportional with
respect to other virtual machines with RELATIVE shares.
|
RESERVE
| See SET RESERVED
|
RESIDENT PAGES (V)
| The average number of nonshared pages of central storage that
are held by a given virtual machine. This is the Resid Storage
Pages column in VMPRF's USER_RESOURCE_UTIL report.
|
RFC
| Request for comments. In the context of this report, an RFC is an
online document that describes a TCP/IP standard (proposed or adopted).
|
RIO/CMD (V)
| The number of real SSCH and RSCH
instructions issued per command.
|
RIO RATE (V)
| The number of real SSCH and RSCH
instructions issued per second.
|
RSU
| Recommend Service Upgrade
|
RTM
| Real Time Monitor
A licensed program realtime monitor and diagnostic tool for
performance monitoring, analysis, and problem solving.
|
Run ID
| An internal use only name used to identify a performance measurement.
|
SET RESERVED (Option)
| This is a CP command that can be used to allow a V=V virtual machine
to have a specified minimum number of pages resident in real storage.
It is used to reduce paging and improve performance for a given
virtual machine.
|
SHARE
| The virtual machine's SHARE setting.
The SET SHARE command and the SHARE directory statement allow
control of the percentage of system resources a virtual machine
receives. These resources include processors, real storage and
paging I/O capability. A virtual machine receives its proportion
of these resources according to its SHARE setting. See Relative and
Absolute Share.
|
Shared Storage
| The portion of a virtual machines storage that is shared among
other virtual machines (such as saved segments). This is usually
represented in pages.
|
SHRPGS
| The number of shared frames currently resident.
|
SIE
|
ESA Architecture instruction to Start Interpretive Execution. This instruction is used
to run a virtual machine in emulation mode.
|
SIE INTCPT/CMD
| The number of exits from SIE which are SIE interceptions per
command or job.
SIE is exited either by interception or interruption. An intercept
is caused by any condition that requires CP interaction such as
I/O or an instruction that has to be simulated by CP.
|
SIE/CMD
| SIE instructions used per command or job.
|
S/390 Real Storage
| On an IBM PC Server 500 system, the amount of real storage that
is available to the System/390 processor.
|
TOT CPU/CMD (V) Server
| The total amount of processor time, in milliseconds,
for the server virtual machine(s).
|
TOT INT
| Total Internal Response Time in seconds. Internal response time
averaged over all
trivial and non-trivial transactions.
|
TOT INT ADJ
| Total internal response time (TOT INT) reported by RTM,
adjusted
to reflect what the response time would have been had CP seen
the actual command rate (as recorded by TPNS). This is a more
accurate measure of internal response time than TOT INT. In addition,
TOT INT ADJ can be directly compared to external response time
(AVG LAST (T)) as they are both based on the same, TPNS-based
measure of command rate.
|
TOT PAGES/USER
| The total number of pages that are associated, on average, with
each end user virtual machine. This is taken from VMPRF report
UCLASS_RESOURCE UTIL and is the sum of resident storage pages,
expanded storage pages, and DASD page slots for the "Users" class.
This is a measure of how many unique pages are touched during
execution of the workload by the average end user.
|
TOTAL
| The total processor utilization for a given measurement summed over
all processors.
|
TOTAL (H)
| See TOTAL. This is the hardware based measurement.
|
Total CPU (I)
| Total CPU time, in seconds, used by a given virtual machine.
This is calculated from INDICATE USER data obtained before and after
the activity being measured. The value shown is final TTIME -
initial TTIME.
|
TOTAL EMUL
| The total emulation state time for all users across all online processors.
This indicates the percentage of time the processors are in emulation state.
|
TOTAL EMUL (H)
| The total emulation state time for all users across all online processors.
This indicates the percentage of time the processors are in emulation state.
|
TPNS
| Teleprocessing Network Simulator. A licensed program terminal and network
simulation tool that provides system performance and response time
information.
|
Transaction
| A user/system interaction as counted by CP.
For a single-user virtual machine a transaction should roughly correspond
to a command. It does not include network or transmission delays and
may include false transactions. False transactions can be those that wait
for an external event, causing them to be counted as multiple transactions, or
those that process more than one command without dropping from queue, causing
multiple transactions to be counted as one.
|
TRACE TABLE (V)
| The size in kilobytes of the CP trace table.
This is the value of the <K bytes> column on the Trace Table line in
the VMPRF System Configuration Report.
|
Transaction (T)
| This is the interval from the time the command is issued until the last
receive prior to the next send. This includes clear screens as a result
of an intervening MORE... or HOLDING condition.
|
TRIV INT
| Trivial Internal Response Time in seconds.
The average response time for transactions that complete with one and
only one drop from Q1 and no drops from Q0, Q2, and Q3.
|
TVR
| Total to Virtual Ratio. This is the ratio of total processor utilization to
virtual processor utilization.
|
TVR (H)
| See TVR.
Total to Virtual Ratio measured by the hardware monitor.
|
T/V Ratio
| See TVR
|
Users
| The number of virtual machines logged on to the system during a
measurement interval that are associated with simulated end users.
This includes active and inactive virtual machines but does not include
service machines.
|
UTIL/PROC (H)
| Per processor utilization reported by the hardware.
|
UTIL/PROC (V)
| Average utilization per processor reported VMPRF.
|
VIO RATE
| The total number of all virtual I/O requests per second for all
users in the system.
|
VIO/CMD
| The average number of virtual I/O requests per command or job
for all users
in the system.
|
VIRT CPU/CMD (V) Server
| Virtual processor time, in milliseconds,
run in the designated server(s) machine
per command.
|
VM Mode
| This field is the virtual machine setting (370, XA or ESA) of the
VSE guest virtual machine in PACE measurements.
|
VM Size
| This field is the virtual machine storage size of the VSE guest
virtual machine in PACE measurements.
|
VMPAF
| Virtual Machine Performance Analysis Facility. A tool used for
performance analysis of VM systems.
|
VMPRF
| VM Performance Reporting Facility.
A licensed program that produces performance reports and history files
from VM/ESA or z/VM monitor data.
|
VSCSs
| The number of virtual machines running VSCS external to VTAM
during a measurement interval.
|
VSE Supervisor
| This field is the VSE supervisor mode used in a PACE measurement.
|
VTAMs
| The number of virtual machines running VTAM during a measurement interval.
|
V=F
|
Virtual equals fixed machine. A virtual machine that has a fixed,
contiguous area of real storage. Unlike V=R, storage does not begin
at page 0. For guests running V=F, CP does not page this area.
Requires the PR/SM hardware feature to be installed.
|
V=R
|
Virtual equals real machine. Virtual machine that has fixed, contiguous area
of real storage starting at page 0. CP does not page this area.
|
V=V
|
Virtual equals virtual machine. Default storage processing. CP pages the
storage of a V=V machine in and out of real storage.
|
WKSET (V)
| The average working set size. This is the scheduler's estimate of
the amount of storage the average user will require, in pages.
|
WKSET (V) Server
| Total working set of a related group of server
virtual machine(s).
|
WRITES/SEC
| The number of page writes per second done for system paging.
|
XSTOR IN/SEC
| The number of pages
per second
read into main storage from expanded storage.
This includes fastpath and non-fastpath pages.
|
XSTOR OUT/SEC
| The number of pages
per second
written from main storage into expanded storage.
|
XSTOR/CMD
| The number of pages read into main storage from expanded storage and
written to expanded storage from main storage per command or job.
|