Start of change

IGW289I D SMS,DSNAME,STATS(ZHLWRITE) Start of Report

Explanation

The message text:   
IGW289I 
D SMS,DSNAME,STATS(ZHLWRITE) Start of Report
DATA SET datasetname                                
STATISTICS SINCE timestamp
SUMMARY:

        TOTAL     %SYNC -------------%ASYNC---------------
  WRITE REQUESTS WRITES   SKIP LNKBSY   ¬EST   MISC DISABL
            stwr   spsy   spsk   splb   spne   spmc   spdi       
                        -------%ASYNC-------
                          MISS  DELAY   DUAL
                          spms   spdl   spdu
DEVICE STATISTICS                                                 
            TOTAL %SYNC--------------- %ASYNC---------------------
SSID DEVNO WRITES WRITES   SKIP LNKBSY   ¬EST   MISC   MISS  DELAY 
dsss  dsdn   dstw   dssy   dssk   dslb   dsne   dsmc   dsms   dsdl
D SMS,DSNAME,STATS(ZHLWRITE) End of Report

This message is issued in response to a D SMS,DSNAME(dsn),STATS(ZHLWRITE) command. It shows the time of the last reset of these statistics, or, if they were never reset, the time that the data set was opened. This message provides the zHyperLink write statistics for the data set in two sections. The first section has the summary information for the data set, and the second section shows the statistics per device. For the first section, only the first asynchronous reason encountered (if any) is counted. For the second section, only devices for which there was I/O activity since the time indicated by timestamp are displayed.

In the message text:
datasetname
The name of the data set. For VSAM data sets, this must be a component name. The sphere name will not work.
timestamp
The time from which zHyperLink write statistics were collected for this data set. This will reflect the time that these statistics were last reset, or if never reset, the time that the data set was opened.
SSID
Storage subsystem ID.
DEVNO
Device number.
TOTAL WRITES
Number of zHyperLink writes for a device.
%SYNC WRITES
Percentage of zHyperLink writes that were completed synchronously.
%ASYNC
Set of reasons for which a zHyperLink write went asynchronous.
SKIP
Percentage of zHyperLink writes for which zHyperLink was not attempted due to a previous zHyperLink failure to the same track that is being written to.
LNKBSY
Percentage of zHyperLink writes that encountered a busy link condition.
^EST
Percentage of zHyperLink writes where zHyperLink write access was not established.
MISC
Percentage of zHyperLink writes that were completed asynchronously due to other reasons.
MISS
Ppercentage of zHyperLink writes that were completed asynchronously due to a cache miss.
DISABL
The percentage of zHyperLink writes where zHyperLink was disabled. See the explanation for message IGW290I for a list of reasons.
DELAY
Percentage of zHyperLink writes that were completed asynchronously due to an operation delay.
DUAL
Percentage of zHyperLink writes that were completed asynchronously due to the other data set in a dual logging request.
stwr
Total number of zHyperLink write requests for the data set. If this number exceeds the display space available, E notation (with a lowercase e) will be used.
spsy
Percentage of the total number of zHyperLink write requests of successful zHyperLink writes.
spsk
Percentage of the total number of zHyperLink write requests that were skipped for zHyperLink due to a previous asynchronous write.
splb
Percentage of the total number of zHyperLink write requests that went asynchronous due to a busy link condition.
spne
Percentage of the total number of zHyperLink write requests that went asynchronous due to not having a complete set of write tokens. A zero or low nonzero number is expected.
smpc
Percentage of the total number of zHyperLink write requests that went asynchronous due to miscellaneous reasons.
spdi
Percentage of the total number of zHyperLink write requests that were disabled for zHyperlink.
spms
Percentage of the total number of zHyperLink write requests that went asynchronous due to a cache miss.
spdl
Percentage of the total number of zHyperLink write requests that went asynchronous due to an operation delay.
spdu
Percentage of the total number of zHyperLink write requests that could have been completed synchronously, but instead went asynchronous due to the other data set in a dual logging request.
dsss
Storage subsystem ID for the device.
dsdn
Subchannel set ID for the device followed by the device number for the device.
dstw
Number of zHyperLink writes for this device. If this number exceeds the display space available, E notation (with a lower case e) will be used.
dssy
Percentage of the zHyperLink writes for this device that were completed synchronously.
dssk
Percentage of the zHyperLink writes for this device that were skipped for zHyperLink due to a previous asynchronous request .
dslb
Percentage of the zHyperLink writes for this device that went asynchronous due to a busy link condition.
dsne
Percentage of the zHyperLink writes for this device that went asynchronous due to not having a write token, or due to an invalid write token.
dsmc
Percentage of the zHyperLink writes for this device that went asynchronous due to miscellaneous reasons.
dsms
Percentage of the zHyperLink writes for this device that went asynchronous due to a cache miss.
dsdl
Percentage of the zHyperLink writes for this device that went asynchronous due to an operation delay.
Note: If any percentage appears as <0.01, it indicates that the number is nonzero but less than 0.01% of the value in stwr or dstw.

System action

None.

Operator response

Contact the system programmer.

System programmer response

The issuer of the command will use the result to diagnose potential zHyperLink write issues.

Problem determination

Depending on the statistics provided, some actions are recommended.
  • For SKIP, a previous zHyperLink write failure may be the cause. Depending on the write pattern, the previous zHyperLink write failure may cause a high percentage of SKIP. Identify the next highest asynchronous percentage reason.
  • For LNKBSY, there may be other zHyperLink activity that is impacting the zHyperLink writes for this data set.
  • For a high percentage of ^EST (zHyperLink write access not established) and MISC, contact IBM support for further diagnosis.
  • For MISS, there may be other access to the data set that is impacting zHyperLink writes. Make sure that there are no other accesses to this data set.
  • For DELAY, there may be other access to the data set or other zHyperLink activity that is impacting zHyperLink writes.
  • For DISABL, message IGW290I may have been issued along with message IGW289I. If so, then check that message for the reason zHyperLink was disabled. Those reasons are counted in SMF type 42 subtype 6 records in the SyncIO section 2 fields.
  • For DUAL, check the zHyperLink write statistics for the other data set specified for dual logging.

Source

Common Measurement Manager (CMM)

Routing code

2,11

Descriptor code

None.

Automation

None.

End of change