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latch: row cache objects

jjkApr 30 2012 — edited Jun 18 2013
Hello everyone,

Note: Apologize for the bad formatting, tried
 but it seems I forgot how to use it

BANNER
----------------------------------------------------------
Oracle Database 11g Release 11.2.0.2.0 - 64bit Production
I've seen high "*latch: row cache objects*" in SP/ASH report for ~14 hours back, when the users were unable to connect to the database. There were, WARNING: inbound connection timed out (ORA-3136) Time: 30-APR-2012 02:24:36 Tracing not turned on. Tns error struct: errors all over the alert log for the duration of 6 minutes of the problem. I've put few records in bold due to which I concluded that the problem was with "dc_users" thing. Can anybody tell me how/where I should proceed forward ? SP report:
Instance Efficiency Indicators
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Buffer Nowait %: 100.00 Redo NoWait %: 100.00
Buffer Hit %: 99.84 Optimal W/A Exec %: 100.00
Library Hit %: 97.43 Soft Parse %: 87.86
Execute to Parse %: 22.54 Latch Hit %: 99.95
Parse CPU to Parse Elapsd %: 0.30 % Non-Parse CPU: 87.83

Shared Pool Statistics Begin End
------ ------
Memory Usage %: 45.09 46.98
% SQL with executions>1: 11.49 13.15
% Memory for SQL w/exec>1: 72.96 21.33

Top 5 Timed Events Avg %Total
~~~~~~~~~~~~~~~~~~ wait Call
Event Waits Time (s) (ms) Time
----------------------------------------- ------------ ----------- ------ ------
latch: row cache objects 6,655 634,260 95306 97.0
log file sync 289,923 6,469 22 1.0
CPU time 5,039 .8
db file sequential read 310,084 2,840 9 .4
log file parallel write 451,706 1,144 3 .2

ASH Report

Analysis Begin Time: 30-Apr-12 02:24:00
Analysis End Time: 30-Apr-12 02:30:00
Elapsed Time: 6.0 (mins)
Begin Data Source: DBA_HIST_ACTIVE_SESS_HISTORY
in AWR snapshot 12185
End Data Source: DBA_HIST_ACTIVE_SESS_HISTORY
in AWR snapshot 12185
Sample Count: 1,385
Average Active Sessions: 38.47
Avg. Active Session per CPU: 1.60
Report Target: None specified

Top User Events DB/Inst: NIKU/niku (Apr 30 02:24 to 02:30)

Avg Active
Event Event Class % Event Sessions
----------------------------------- --------------- ---------- ----------
latch: row cache objects Concurrency 75.45 29.03
CPU + Wait for CPU CPU 9.75 3.75
log file sync Commit 3.83 1.47
db file sequential read User I/O 3.61 1.39
-------------------------------------------------------------

Top Event P1/P2/P3 Values DB/Inst: NIKU/niku (Apr 30 02:24 to 02:30)

Event % Event P1 Value, P2 Value, P3 Value % Activity
------------------------------ ------- ----------------------------- ----------
Parameter 1 Parameter 2 Parameter 3
-------------------------- -------------------------- --------------------------
latch: row cache objects 75.60 "42287858200","279","0" 75.60
address number tries

  1* select addr, latch#, child#, name, misses, gets from v$latch_children where name like '%row%cache%objec%'  order by gets , misses
niku> /

ADDR                 LATCH#     CHILD# NAME                                                   MISSES       GETS
---------------- ---------- ---------- -------------------------------------------------- ---------- ----------
0000000A16FF21C8        279         26 row cache objects                                           0          0
0000000A16FF14C8        279          2 row cache objects                                           0          0
00000009D88D7ED8        279          3 row cache objects                                           0          0
0000000A16FF1B48        279         14 row cache objects                                           0          0
00000009D88D8558        279         15 row cache objects                                           0          0
0000000A16FF1CE8        279         17 row cache objects                                           0          0
0000000A26265A28        279         19 row cache objects                                           0          0
0000000A16FF1E88        279         20 row cache objects                                           0          0
00000009D88D8898        279         21 row cache objects                                           0          0
0000000A26265BC8        279         22 row cache objects                                           0          0
0000000A16FF2028        279         23 row cache objects                                           0          0
00000009D88D8A38        279         24 row cache objects                                           0          0
0000000A26265D68        279         25 row cache objects                                           0          0
00000009D88D8BD8        279         27 row cache objects                                           0          0
0000000A26265F08        279         28 row cache objects                                           0          0
00000009D88D8D78        279         30 row cache objects                                           0          0
0000000A262660A8        279         31 row cache objects                                           0          0
0000000A16FF2508        279         32 row cache objects                                           0          0
0000000A16FF26A8        279         35 row cache objects                                           0          0
00000009D88D90B8        279         36 row cache objects                                           0          0
0000000A262663E8        279         37 row cache objects                                           0          0
0000000A262668C8        279         46 row cache objects                                           0          0
0000000A26266A68        279         49 row cache objects                                           0          0
0000000A16FF2368        279         29 row cache objects                                           0         11
0000000A16FF2848        279         38 row cache objects                                           0        116
0000000A16FF29E8        279         41 row cache objects                                           0        200
00000009D88D93F8        279         42 row cache objects                                           0        318
00000009D88D9258        279         39 row cache objects                                           0       1010
0000000A16FF2EC8        279         50 row cache objects                                           0       1406
00000009D88D9598        279         45 row cache objects                                           0       1472
0000000A26266588        279         40 row cache objects                                           0       1705
0000000A26266728        279         43 row cache objects                                           0       7383
0000000A16FF2B88        279         44 row cache objects                                           0      32346
00000009D88D98D8        279         51 row cache objects                                          19      63948
0000000A26265888        279         16 row cache objects                                           0      88045
0000000A26266248        279         34 row cache objects                                           0     141176
00000009D88D9738        279         48 row cache objects                                           0     326672
0000000A16FF19A8        279         11 row cache objects                                         867    1770385
00000009D88D8078        279          6 row cache objects                                           9    1979542
0000000A16FF2D28        279         47 row cache objects                                           2    3435018
00000009D88D86F8        279         18 row cache objects                                        2557   14956121
0000000A26265068        279          1 row cache objects                                         224   24335868
0000000A262653A8        279          7 row cache objects                                       29760  133991553
00000009D88D8F18        279         33 row cache objects                                       60612  677263122
00000009D88D83B8        279         12 row cache objects                                       23981  739014460
0000000A26265208        279          4 row cache objects                                    19973399  852043775
0000000A26265548        279         10 row cache objects                                      280137  856097342
00000009D88D8218        279          9 row cache objects                                   715879777 1219000976
0000000A262656E8        279         13 row cache objects                                     3856073 2397402780
0000000A16FF1668        279          5 row cache objects                                    12763217 2920278217
*0000000A16FF1808        279          8 row cache objects                                    67329804 4145389092*

51 rows selected.

niku> list
  1 select addr, latch#, child#, name, misses, gets from v$latch_children where name like '%row%cache%objec%'  order by gets , misses
niku> select distinct s.kqrstcln latch#,r.cache#,r.parameter name,r.type,r.subordinate#
from v$rowcache r,x$kqrst s
where r.cache#=s.kqrstcid
order by 1,4,5;  2    3    4

    LATCH#     CACHE# NAME                                               TYPE        SUBORDINATE#
---------- ---------- -------------------------------------------------- ----------- ------------
         1          3 dc_rollback_segments                               PARENT
         2          1 dc_free_extents                                    PARENT
         3          4 dc_used_extents                                    PARENT
         4          2 dc_segments                                        PARENT
         5          0 dc_tablespaces                                     PARENT
         6          5 dc_tablespace_quotas                               PARENT
         7          6 dc_files                                           PARENT
         *8         10 dc_users                                           PARENT*
         *8          7 dc_users                                           SUBORDINATE            0*
         *8          7 dc_users                                           SUBORDINATE            1*
         *8          7 dc_users                                           SUBORDINATE            2*
         9          8 dc_objects                                         PARENT
         9          8 dc_object_grants                                   SUBORDINATE            0
        10         17 dc_global_oids                                     PARENT
        11         12 dc_constraints                                     PARENT
        12         13 dc_sequences                                       PARENT
        13         16 dc_histogram_defs                                  PARENT
        13         16 dc_histogram_data                                  SUBORDINATE            0
        13         16 dc_histogram_data                                  SUBORDINATE            1
        14         54 dc_sql_prs_errors                                  PARENT
        15         32 kqlsubheap_object                                  PARENT
        16         19 dc_table_scns                                      PARENT
        16         19 dc_partition_scns                                  SUBORDINATE            0
        17         18 dc_outlines                                        PARENT
        18         14 dc_profiles                                        PARENT
        19         47 realm cache                                        PARENT
        19         47 realm auth                                         SUBORDINATE            0
        20         48 Command rule cache                                 PARENT
        21         49 Realm Object cache                                 PARENT
        21         49 Realm Subordinate Cache                            SUBORDINATE            0
        22         46 Rule Set Cache                                     PARENT
        23         34 extensible security user and rol                   PARENT
        24         35 extensible security principal pa                   PARENT
        25         37 extensible security UID to princ                   PARENT
        26         36 extensible security principal na                   PARENT
        27         33 extensible security principal ne                   PARENT
        28         38 XS security class privilege                        PARENT
        29         39 extensible security midtier cach                   PARENT
        30         43 AV row cache 1                                     PARENT
        31         44 AV row cache 2                                     PARENT
        32         45 AV row cache 3                                     PARENT
        33         15 global database name                               PARENT
        34         20 rule_info                                          PARENT
        35         21 rule_or_piece                                      PARENT
        35         21 rule_fast_operators                                SUBORDINATE            0
        36         23 dc_qmc_ldap_cache_entries                          PARENT
        37         52 qmc_app_cache_entries                              PARENT
        38         53 qmc_app_cache_entries                              PARENT
        39         27 qmtmrcin_cache_entries                             PARENT
        40         28 qmtmrctn_cache_entries                             PARENT
        41         29 qmtmrcip_cache_entries                             PARENT
        42         30 qmtmrctp_cache_entries                             PARENT
        43         31 qmtmrciq_cache_entries                             PARENT
        44         26 qmtmrctq_cache_entries                             PARENT
        45          9 qmrc_cache_entries                                 PARENT
        46         50 qmemod_cache_entries                               PARENT
        47         24 outstanding_alerts                                 PARENT
        48         22 dc_awr_control                                     PARENT
        49         25 SMO rowcache                                       PARENT
        50         40 sch_lj_objs                                        PARENT
        51         41 sch_lj_oids                                        PARENT

61 rows selected.

niku> select parameter, gets from v$rowcache order by gets desc;

PARAMETER                              GETS
-------------------------------- ----------
dc_users                         2802019571
dc_tablespaces                   2405092307
dc_objects                       1815427326                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     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Locked on Jul 16 2013
Added on Apr 30 2012
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