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Log Bytes report

The Log Bytes report supplies information about the distribution of log records in the Db2 log. The Log Bytes report focuses on the type, size and distribution of log records, and not on the actual data contained in the log records.

Filters that you specify in the log scan are not used for selecting records that BMC AMI Log Master reports in a Log Bytes report.

Related topic

 Reference-of-default-Log-Master-reports

Use the Log Bytes report for tuning purposes, to help you reduce unnecessary overhead in the log. The Log Bytes report displays the following information about log records:

  • Counts of log record types
  • Total number of bytes used by the log records
  • Percentage of space the log records use

To request a Log Bytes report

  1. From any task dialog (any option from 0 through 7 under the Actions category on the Main Menu), select the Define Report and File Outputs option.
  2. On the Output Options panel, select Log Bytes.

When you generate a Log Bytes report, BMC AMI Log Master cannot include any other forms of output in the same log scan, such as other reports or SQL. To generate other forms of output for the same work ID add an additional separate log scan step.

Example of a Log Bytes report 

Click here to see an example of a Log Bytes report.

Date: 2022-01-18     BMC AMI Log Master for Db2 - V13.01.00        Page:       1
Time: 16.55.19       Copyright BMC Software, Inc. 1995-2023
                          Log Bytes Report, By Plan
--------------------------------------------------------------------------------
From: Date 2022-01-18 16.25.17.774795
  To: Date 2022-01-18 16.40.17.774795
  Total Bytes: 2262820
--------------------------------------------------------------------------------
Report Information:
Work ID    : LOGMSTR.LOGBYTESRPT         Run Number:    1  Subsystem: DEMO
Description:
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
URID Records:
Plan: 'DSNREXX '
                                               Count          Bytes  Log Percent
                                       -------------  -------------  -----------
Urid                                               8           1044      0.04614
Savepoint                                         18           1602      0.07080
DM Committed                                     648         152908      6.75741
DM Rolledback                                      0              0      0.00000
Compensation                                       0              0      0.00000
Exclusive Lock                                    36           4392      0.19409
Invalidate Obj                                     5            660      0.02917
                                       =============  =============  ===========
                                                 715         160606      7.09760
Plan: 'DSNTEP2 '
                                               Count          Bytes  Log Percent
                                       -------------  -------------  -----------
Urid                                              16           2088      0.09227
Savepoint                                         38           3382      0.14946
DM Committed                                     344         157617      6.96551
DM Rolledback                                      0              0      0.00000
Compensation                                       0              0      0.00000
Exclusive Lock                                     4            488      0.02157
Invalidate Obj                                     2            264      0.01167
                                       =============  =============  ===========
                                                 404         163839      7.24048
URID Totals:
                                               Count          Bytes  Log Percent
                                       -------------  -------------  -----------
Urid                                            1416         184788      8.16627
Savepoint                                        498          44322      1.95871
DM Committed                                    3801        1780250     78.67396
DM Rolledback                                      0              0      0.00000
Compensation                                       0              0      0.00000
Exclusive Lock                                    40           4880      0.21566
Invalidate Obj                                     7            924      0.04083
                                       =============  =============  ===========
                                                5762        2015164     89.05543
--------------------------------------------------------------------------------

Space Name: D8297F40.T8297F40
DBID:PSID: 064B:0002
Record Type                                    Count          Bytes  Log Percent
-------------------------------------  -------------  -------------  -----------
Space Map Records                                 55           6896      0.30475
Page Format Records                               18           3276      0.14478
Header Format Records                             91         570270     25.20174
Segment Alloc/Dealloc Records                     18           2466      0.10898
Pageset Open                                      19           4708      0.20806
Pageset Close                                     19           2356      0.10412
Pageset Write                                     55          11998      0.53022
DBE Table w/ Exception Data                      495         152960      6.75971
Sysobd                                            18          16164      0.71433
Dummy CLR                                         34           4556      0.20134
                                       =============  =============  ===========
                                                 822         775650     34.27802
Space Name: D8297F40.T8291FIV
DBID:PSID: 064B:0005
Record Type                                    Count          Bytes  Log Percent
-------------------------------------  -------------  -------------  -----------
Header Format Records                              5           5478      0.24209
Pageset Open                                       1            252      0.01114
Pageset Close                                      1            124      0.00548
Pageset Write                                      2            524      0.02316
DBE Table w/ Exception Data                       62          20480      0.90507
                                       =============  =============  ===========
                                                  71          26858      1.18693
DM Totals:
Record Type                                    Count          Bytes  Log Percent
-----------------------------          -------------  -------------  -----------
Inserts                                          308          84906      3.75222
Updates                                          429         215999      9.54557
Delete                                           266          73048      3.22818
Index Updates                                   1418         333484     14.73754
Space Map Records                                166          21104      0.93264
Page Format Records                               18           3276      0.14478
Header Format Records                            106         586784     25.93154
Page Compaction Records                            3            348      0.01538
Segment Alloc/Dealloc Records                     18           2466      0.10898
Lob Space Map Alloc Records                       52           9244      0.40852
Pageset Open                                      22           5464      0.24147
Pageset Close                                     58           7192      0.31783
Pageset Write                                    161          35270      1.55867
Locking Records                                   40           4880      0.21566
DBE Table w/ Exception Data                      681         214400      9.47490
DBD Virtual Memory Copy                          214          36860      1.62894
Lob Map Change                                    26           5636      0.24907
Lob Data Page Change                              43         171877      7.59570
Sysobd                                            18          16164      0.71433
Dummy CLR                                         34           4556      0.20134
Add/Alter Column Diagnostic                        1             98      0.00433
                                       =============  =============  ===========
                                                4082        1833056     81.00759
--------------------------------------------------------------------------------
System Event Records:
Record Type                                    Count          Bytes  Log Percent
-------------------------------------- -------------  -------------  -----------
Trace Records                                    222         106012      4.68495
Non-URID Related Lock Records                     45           8100      0.35796
Create DS/Extend/Drop List Records                42          56784      2.50944
System Event Totals:                   =============  =============  ===========
                                                 309         170896      7.55235
--------------------------------------------------------------------------------
Page Overhead and Free Bytes:
                          Page Count     CI Overhead     Free Bytes  Log Percent
                       -------------   -------------  -------------  -----------
                                 552           23824           5010      1.27425


Log Bytes report contents

The information presented in the Log Bytes report is grouped into the following sections:

  • URID records
  • data management records, reported by table space (DBID and PSID), and divided into the following record subtypes:
    • inserts, updates, and deletes (This section includes XML records.)
    • compensation
    • index
    • space map
    • page format
    • pointer update
    • page compaction
    • pageset (open, close, and write)
    • locking
    • LOB
    • database exception (DBE) table update
    • DBE table with piece data
  • checkpoint records
  • diagnostic records
  • SYSCOPY records
  • system event records
  • miscellaneous records
  • Db2 page overhead information, including totals for
    • number of pages
    • amount of CI bytes on those pages
    • amount of free space on the pages

Log Bytes report ordering

BMC AMI Log Master orders most sections of the Log Bytes report by DB2 record type and subtype. BMC AMI Log Master orders records in the diagnostic records section by member ID, and includes information about each member.

You can order this report by the following unit of recovery (URID) options:

  • Plan name
  • Authorization ID
  • Connection type
  • Connection ID
  • Correlation ID
  • (BMC.DB2.SPE2310) Logical unit of work identifier (LUWID)

 

Tip: For faster searching, add an asterisk to the end of your partial query. Example: cert*

BMC AMI Log Master for Db2 13.1