DB2 runstats和reorg操做

[db2inst1@xifenfei ~]$ db2 connect to xff

 

    Database Connection Information

 

  Database server        = DB2 /LINUX 9.5.9

  SQL authorization ID   = DB2INST1

  Local database alias   = XFF

 

[db2inst1@xifenfei ~]$ db2 list tables

 

Table /View                      Schema          Type  Creation time            

------------------------------- --------------- ----- --------------------------

T_01XFF                         DB2INST1        T     2012-04-11-18.23.05.723478

T_02XFF                         DB2INST1        T     2012-04-11-18.30.26.639326

T_03XFF                         DB2INST1        T     2012-04-11-21.33.12.479480

 

   3 record(s) selected.

 

[db2inst1@xifenfei ~]$ db2 "select STATS_TIME from syscat.tables where tabname in('T_01XFF','T_02XFF','T_03XFF')"

 

STATS_TIME               

--------------------------

2012-04-12-04.35.07.539790

2012-04-11-19.55.12.023748

2012-04-11-22.20.07.016905

 

   3 record(s) selected.

 

--收集表和索引統計信息,包括數據分佈

[db2inst1@xifenfei ~]$ db2 "runstats on table db2inst1.t_01xff on all columns

with distribution and detailed indexes all"

DB20000I  The RUNSTATS command completed successfully.

[db2inst1@xifenfei ~]$ db2 "select STATS_TIME from syscat.tables where tabname in('T_01XFF')"

 

STATS_TIME               

--------------------------

2012-04-28-23.43.23.904759

 

   1 record(s) selected.

 

--收集索引統計信息,若是表沒有被收集,也會同時對錶收集統計信息,對不會收集數據分佈信息

[db2inst1@xifenfei ~]$ db2 "runstats on table db2inst1.t_02xff for  indexes all"

DB20000I  The RUNSTATS command completed successfully.

 

 

[db2inst1@xifenfei ~]$ db2 "select STATS_TIME from syscat.tables where tabname in('T_01XFF','T_02XFF')"

 

STATS_TIME               

--------------------------

2012-04-28-23.43.23.904759

2012-04-28-23.44.39.762858

 

   2 record(s) selected.

db2 reorg操做

--刪除部分表數據

[db2inst1@xifenfei ~]$ db2 "delete from t_01xff"

DB20000I  The SQL command completed successfully.

[db2inst1@xifenfei ~]$ db2 "delete from t_03xff"

DB20000I  The SQL command completed successfully.

 

--reorgchk檢查是否須要進行reorg

[db2inst1@xifenfei ~]$ db2 reorgchk on schema db2inst1

 

Doing RUNSTATS ....

 

 

Table statistics:

 

F1: 100 * OVERFLOW / CARD < 5

F2: 100 * (Effective Space Utilization of Data Pages) > 70

F3: 100 * (Required Pages / Total Pages) > 80

 

SCHEMA.NAME                     CARD     OV     NP     FP ACTBLK    TSIZE  F1  F2  F3 REORG

----------------------------------------------------------------------------------------

Table: DB2INST1.T_01XFF

                                    0      0      0     42      -        0   0   0   0 -**

Table: DB2INST1.T_02XFF

                                  371      0     42     42      -   152110   0 100 100 ---

Table: DB2INST1.T_03XFF

                                    0      0      0     83      -        0   0   0   0 -**

----------------------------------------------------------------------------------------

 

Index statistics:

 

F4: CLUSTERRATIO or normalized CLUSTERFACTOR > 80

F5: 100 * (Space used on leaf pages / Space available on non-empty leaf pages) > MIN(50, (100 - PCTFREE))

F6: (100 - PCTFREE) * (Amount of space available in an index with one less level / Amount of space required for all keys) < 100

F7: 100 * (Number of pseudo-deleted RIDs / Total number of RIDs) < 20

F8: 100 * (Number of pseudo-empty leaf pages / Total number of leaf pages) < 20

 

SCHEMA.NAME                 INDCARD  LEAF ELEAF LVLS  NDEL    KEYS LEAF_RECSIZE NLEAF_RECSIZE LEAF_PAGE_OVERHEAD NLEAF_PAGE_OVERHEAD  F4  F5  F6  F7  F8 REORG 

--------------------------------------------------------------------------------------------------------------------------------------------------------------

Table: DB2INST1.T_01XFF

Index: DB2INST1.I_T_01XFF

                                   0     3     3    2     0       0            2             2                822                 822 100   0   -   0 100 ----*

--------------------------------------------------------------------------------------------------------------------------------------------------------------

 

CLUSTERRATIO or normalized CLUSTERFACTOR (F4) will indicate REORG is necessary

for indexes that are not in the same sequence as the base table. When multiple

indexes are defined on a table, one or more indexes may be flagged as needing

REORG.  Specify the most important index for REORG sequencing.

 

Tables defined using the ORGANIZE BY clause and the corresponding dimension

indexes have a '*' suffix to their names. The cardinality of a dimension index

is equal to the Active blocks statistic of the table.

 

--離線reorg index

[db2inst1@xifenfei ~]$ db2 reorg table db2inst1.t_01xff index DB2INST1.I_T_01XFF allow read access

DB20000I  The REORG command completed successfully.

 

--在線reorg table

[db2inst1@xifenfei ~]$ db2 reorg table db2inst1.t_01xff inplace allow write access

DB20000I  The REORG command completed successfully.

DB21024I  This command is asynchronous and may not be effective immediately.

 

[db2inst1@xifenfei ~]$ db2 reorg table db2inst1.t_03xff inplace allow write access

DB20000I  The REORG command completed successfully.

DB21024I  This command is asynchronous and may not be effective immediately.

 

--證實異步操做完成

[db2inst1@xifenfei ~]$ ps -ef| grep db2reo

db2inst1  1496  1311  0 00:24 pts /1    00:00:00 grep db2reo

 

--檢查reorg操做結果

[db2inst1@xifenfei ~]$ db2 reorgchk on schema db2inst1

 

Doing RUNSTATS ....

 

 

Table statistics:

 

F1: 100 * OVERFLOW / CARD < 5

F2: 100 * (Effective Space Utilization of Data Pages) > 70

F3: 100 * (Required Pages / Total Pages) > 80

 

SCHEMA.NAME                     CARD     OV     NP     FP ACTBLK    TSIZE  F1  F2  F3 REORG

----------------------------------------------------------------------------------------

Table: DB2INST1.T_01XFF

                                    0      0      0      1      -        0   0   -   0 ---

Table: DB2INST1.T_02XFF

                                  371      0     42     42      -   152110   0 100 100 ---

Table: DB2INST1.T_03XFF

                                    0      0      0      1      -        0   0   -   0 ---

----------------------------------------------------------------------------------------

 

Index statistics:

 

F4: CLUSTERRATIO or normalized CLUSTERFACTOR > 80

F5: 100 * (Space used on leaf pages / Space available on non-empty leaf pages) > MIN(50, (100 - PCTFREE))

F6: (100 - PCTFREE) * (Amount of space available in an index with one less level / Amount of space required for all keys) < 100

F7: 100 * (Number of pseudo-deleted RIDs / Total number of RIDs) < 20

F8: 100 * (Number of pseudo-empty leaf pages / Total number of leaf pages) < 20

 

SCHEMA.NAME                 INDCARD  LEAF ELEAF LVLS  NDEL    KEYS LEAF_RECSIZE NLEAF_RECSIZE LEAF_PAGE_OVERHEAD NLEAF_PAGE_OVERHEAD  F4  F5  F6  F7  F8 REORG 

--------------------------------------------------------------------------------------------------------------------------------------------------------------

Table: DB2INST1.T_01XFF

Index: DB2INST1.I_T_01XFF

                                   0     1     0    1     0       0            2             2                822                 822 100   -   -   0   0 -----

--------------------------------------------------------------------------------------------------------------------------------------------------------------

 

CLUSTERRATIO or normalized CLUSTERFACTOR (F4) will indicate REORG is necessary

for indexes that are not in the same sequence as the base table. When multiple

indexes are defined on a table, one or more indexes may be flagged as needing

REORG.  Specify the most important index for REORG sequencing.

 

Tables defined using the ORGANIZE BY clause and the corresponding dimension

indexes have a '*' suffix to their names. The cardinality of a dimension index

is equal to the Active blocks statistic of the table.

Please refer to : http://www.xifenfei.com/3013.html