I/O Queuing Activity Report (Analyzer report)
The I/O Queuing Activity Report displays I/O configuration and activity data.
It provides information about:
the IODF (input/output definition file)
This VSAM linear data set contains I/O definition information.
I/O processor utilization
One or more I/O processors are present for the channel subsystem. They manage and schedule I/O requests to devices within LCUs.
for each Logical Control Unit or LCU, the mapping and activity of its channel paths and physical control units
For dynamically managed channel paths, additional information is available.
Use the IOQ Analyzer control statement to produce the I/O Queuing Activity Report.
The data for this report is obtained by using the IOQ and DEVICE Extractor control statements.
There are three sections to the I/O Queuing Activity Report:
- IODF Section
- I/O Processor Utilization Section
- LCU Configuration and Activity Section
The following figure shows an example of the I/O Queuing Activity Report.
BMC SOFTWARE, INC. BMC SOFTWARE, INC. REPORT DATE: DD MMM YY 17.48
ACTL 06 JUL YY 17.00.00 06 JUL YY 17.45.00 HOUSTON, TX. SYSTEM ID: SJSC Z v.rr.n
BASED ON REC TYPE/# RECS/# SAMPLES/REC HOURS: 78-3/14/556/0.47
---------------------------------------------------------- IODF SECTION ----------------------------------------------------------
IODF = 48 CREATED = 05/09/YYYY-23.17.30 ACTION = POR
----------------------------------------------------- I/O PROCESSORS SECTION -----------------------------------------------------
-INITIATIVE QUEUE- ------ IOP UTILIZATION ------- -- % I/O REQUESTS RETRIED -- -------- RETRIES / SSCH ---------
ACTIVITY AVG Q % IOP I/O START INTERRUPT CP DP CU DV CP DP CU DV
IOP RATE LNGTH BUSY RATE RATE ALL BUSY BUSY BUSY BUSY ALL BUSY BUSY BUSY BUSY
--- --------- ------- ----- ------- ------- ---- ---- ---- ---- ---- ----- ----- ----- ----- -----
00 2,530.49 0 5.18 2,530.5 2,628.4 1.5 0 0 0.6 0.8 0.01 0 0 0.01 0.01
01 3,647.89 0 7.34 3,647.9 4,090.4 1.2 0 0.8 0.1 0.2 0.01 0 0.01 0 0
02 122.83 0 0.18 122.81 147.23 1.1 0.9 0 0.1 0.1 0.01 0.01 0 0 0
03 4,939.55 0.01 5.35 4,939.5 5,207.4 3.3 2.4 0 0.4 0.5 0.03 0.02 0 0 0.01
04 2,541.55 0 2.95 2,541.5 2,644.7 2.7 2.5 0.1 0 0.1 0.03 0.03 0 0 0
05 4,018.10 0 5.12 4,018.1 4,290.0 7.9 0.8 0 4.9 2.3 0.09 0.01 0 0.05 0.02
SUMMARY: 17,800.4 0 4.35 17,800 19,008 3.6 1.2 0.2 1.4 0.8 0.04 0.01 0 0.01 0.01
-------------------------------------------------- LOGICAL Control UNITS SECTION ---------------------------------------------------
AVG AVG AVG HYPERPAV AVG DATA
CNTL --- DCM --- CHAN PREF CHPID % DP % CU CUB CMR CONTNTN DELAY Q CSS I/O MAX OPEN XFER
LCU UNIT MIN MAX DEF PATH PATH TAKEN BUSY BUSY DLY DLY RATE LENGTH DLY WAIT USED EXCH CONC
---- ---- --- --- --- -- -- ------- ----- ----- ----- ----- ------- ------- ----- ---- ---- ----- -----
006E 4900 89 1.164 0 0 0 0.11
DF 1.202 0 0 0 0.08
EF 1.167 0 0 0 0.11
**** 3.533 0 0 0 592.5 0 0 0 0 0 0 0
006F 4A00 89 2.232 0 0 0 0.06
DF 2.294 0 0 0 0.04
EF 2.276 0 0 0 0.05
**** 6.802 0 0 0 566.5 0 0 0 0 0 0 0
0079 5505 A8 OFFLINE
AC 0.014 0 0 0 0
5506 B0 OFFLINE
B8 0.018 0 0 0 0
**** 0.032 0 0 0 0 0 0 0
008B 8300 8E 21.772 0 6.26 0 0.18
FD 21.638 0 6.34 0 0.18
**** 43.410 0 6.30 0 13.3K 0 0 0 0 0
008C 833C 8E 159.395 0 0.51 0 0.15
FD 159.621 0 0.51 0 0.15
**** 319.017 0 0.51 0 78.9K 0 0 0 0 0
I/O Queuing Activity Report field descriptions
The table below describes in the I/O Queuing Activity Report.
Field | Description | |
|---|---|---|
IODF SECTION | ||
IODF | two-character hexadecimal suffix for the IODF data set name | |
CREATED | date and time this IODF data set was created | |
ACTION | text indicating how this IODF data set was activated | |
I/O PROCESSORS SECTION | ||
IOP | I/O processor (IOP) numeric identifier; the IOP data section is sorted according ascending IOP numbers | |
Initiative Queue | for each IOP, there is one initiative queue | |
ACTIVITY RATE | rate, per second, at which the channel subsystem places requests on the I/O processor’s initiative queue | |
AVG Q LNGTH | average number of entries present on the initiative queue | |
IOP Utilization | ||
% IOP BUSY | ratio of the number of times that the IOP was found busy and the total number of samples taken | |
I/O START RATE | rate, per second, at which I/O requests are initiated on this IOP | |
INTERRUPT RATE | rate, per second, at which interrupts are processed on this IOP | |
% I/O Requests Retried, includes all initial I/O requests and all requests that were retried | ||
ALL | percentage of I/O requests that were retried for any reason | |
CP BUSY | percentage of I/O requests that were retried because of CHANNEL busy conditions | |
DP BUSY | percentage of I/O requests that were retried because of DIRECTOR PORT busy conditions | |
CU BUSY | percentage of I/O requests that were retried because of Control UNIT busy condition | |
DV BUSY | percentage of I/O requests that were retried because of DEVICE busy conditions | |
Retries / SSCH, versus the number of initial I/O requests | ||
ALL | ratio of I/O requests that were retried for any reason, | |
CP BUSY | ratio of I/O requests that were retried because of CHANNEL busy conditions | |
DP BUSY | ratio of I/O requests that were retried because of DIRECTOR PORT busy conditions | |
CU BUSY | ratio of I/O requests that were retried because of Control UNIT busy conditions | |
DV BUSY | ratio of I/O requests that were retried because of DEVICE busy conditions | |
LOGICAL Control UNITS SECTION | ||
LCU | Logical Control Unit identifier; a four-digit hexadecimal number; an LCU is a logical entity representing one or more physical control units | |
CNTL UNIT | four-digit hexadecimal number of each physical control unit pertaining to this LCU; an LCU can have up to four physical control units | |
DCM This data is available only for LCUs with DCM managed channel paths. Additionally, for all DCM-managed channel paths, the I/O activity rate, the director port contention, and the control unit contention are computed and shown. Note that these values can include managed channels that were only partially online. | ||
MIN | minimum number of DCM-managed channels for this LCU for the reporting period | |
MAX | maximum number of DCM-managed channels for this LCU for the reporting period | |
DEF | number of installation-defined managed channels for the LCU | |
CHAN PATH | two-digit hexadecimal number of each channel path that is assigned to this LCU An LCU can have up to four channel paths. Four asterisks (****) in this column indicate a summary line for all channel paths connected to this LCU. | |
PREF PATH | path attribute; displayed for subsystems that support Preferred Pathing (for example, the 1750) The path attribute values that can appear are preferred (PF), nonpreferred (NP), and not specified (NS). | |
CHPID TAKEN | rate, per second, of I/O requests handled by each CHPID during the reporting period If a channel path was offline or moved offline or online during the reporting period, this column could contain the following: OFFLINENOW OFFLINENOW ONLINE | |
% DP BUSY | percentage of I/O requests that were deferred because a director port was busy; this figure is a measure of director port contention | |
% CU BUSY | percentage of I/O requests that were deferred because the control unit was busy; this figure is a measure of control unit contention along each channel path | |
AVG CUB DLY | average number of milliseconds that the I/O request for the channel path waited because the control unit was busy | |
AVG CMR DLY | average number of milliseconds for a start or resume function needed before the first command of the channel program sent to the device is marked Accepted by the device | |
CONTNTN RATE | rate, per second, at which delayed I/O requests are placed on the Control Unit Header (CU-HDR) by the IOP | |
DELAY Q LENGTH | average number of delayed I/O requests present on the CU-HDR | |
AVG CSS DLY | average number of milliseconds for the start or resume function needed from the acceptance by the subchannel until the channel subsystem attempts to start the function; this figure is a measure of channel subsystem contention along each LCU | |
AVG SRVC TIME (MS) | average number of milliseconds it took to complete an I/O request for all devices attached to this LCU that were monitored by the device activity sampler This field is present only if SMF- type 74-1 records are available. | |
AVG IOSQ TIME (MS) | average number of milliseconds that I/O requests had to wait before a SSCH instruction was issued to queue the request, for all devices attached to this LCU that were monitored by the device activity sampler This field is present only if SMF- type 74-1 records are available. | |
HYPERPAV I/O WAIT | ratio of the number of times an I/O could not start (because no HyperPAV aliases were available) to the number of successful I/Os | |
HYPERPAV MAX USED | maximum number of concurrently in-use HyperPAV alias devices for the specified LCU during the interval For more information, see the description of the HPVHWM parameter in the IOQ Extractor control statement. | |
AVG OPEN EXCH | estimated average number of concurrent active I/O operations This value is calculated as follows:
where
| |
DATA XFER CONC | data transfer concurrency This value is calculated as follows:
where
| |
ALIAS MANAGEMENT GROUP REPORT | ||
AMG | Alias Management Group; a four-digit hexadecimal number; | |
CNTL UNIT | four-digit hexadecimal number of each physical control unit pertaining to this AMG; an AMG can have up to four physical control units | |
% DP BUSY | percentage of I/O requests that were deferred because a director port was busy; this figure is a measure of director port contention | |
% CU BUSY | percentage of I/O requests that were deferred because the control unit was busy; this figure is a measure of control unit contention along each channel path | |
AVG CUB DLY | average number of milliseconds that the I/O request for the channel path waited because the control unit was busy | |
AVG CMR DLY | average number of milliseconds for a start or resume function needed before the first command of the channel program sent to the device is marked Accepted by the device | |
CONTNTN RATE | rate, per second, at which delayed I/O requests are placed on the Control Unit Header (CU-HDR) by the IOP | |
DELAY Q LENGTH | average number of delayed I/O requests present on the CU-HDR | |
AVG CSS DLY | average number of milliseconds for the start or resume function needed from the acceptance by the subchannel until the channel subsystem attempts to start the function; this figure is a measure of channel subsystem contention along each LCU | |
AVG SRVC TIME (MS) | average number of milliseconds it took to complete an I/O request for all devices attached to this LCU that were monitored by the device activity sampler This field is present only if SMF- type 74-1 records are available. | |
AVG IOSQ TIME (MS) | average number of milliseconds that I/O requests had to wait before a SSCH instruction was issued to queue the request, for all devices attached to this LCU that were monitored by the device activity sampler This field is present only if SMF- type 74-1 records are available. | |
HYPERPAV I/O WAIT | ratio of the number of times an I/O could not start (because no HyperPAV aliases were available) to the number of successful I/Os | |
HYPERPAV MAX USED | maximum number of concurrently in-use HyperPAV alias devices for the specified LCU during the interval For more information, see the description of the HPVHWM parameter in the IOQ Extractor control statement. | |
AVG OPEN EXCH | estimated average number of concurrent active I/O operations This value is calculated as follows:
where
| |
DATA XFER CONC | data transfer concurrency This value is calculated as follows:
where
| |
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