转由于PGA单个进程只能使用4GB大小限制导致Oracle 11g版本AUTO SQL TUNING遇到ORA-04030错误

作者：dbdream 发布：2019-06-12 11:02 分类：Oracle, oracle 11g 抢沙发

今天，用友NC的一个数据库又出问题了，这次遇到的是ORA-04030错误：

01
Mon Jun 10 22:05:19 2019

02
Dumping diagnostic data in directory=[cdmp_20190610220519], requested by (instance=1, osid=101922 (J001)), summary=[incident=48330].

03
Errors in file /u01/app/oracle/diag/rdbms/ncdb1/ncdb1/incident/incdir_48329/ncdb1_j001_101922_i48329.trc:

04
ORA-04030: out of process memory when trying to allocate 82456 bytes (pga heap,control file i/o buffer)

05
ORA-04030: out of process memory when trying to allocate 432 bytes (kxs-heap-c,kprbalo temp memory)

06
Dumping diagnostic data in directory=[cdmp_20190610220521], requested by (instance=1, osid=101922 (J001)), summary=[incident=48331].

07
Mon Jun 10 22:06:19 2019

08
Sweep [inc2][48331]: completed

09
Sweep [inc2][48329]: completed

10
Mon Jun 10 22:08:56 2019

11
Errors in file /u01/app/oracle/diag/rdbms/ncdb1/ncdb1/trace/ncdb1_j001_101922.trc  (incident=48332):

12
ORA-04030: out of process memory when trying to allocate 432 bytes (kxs-heap-c,kprbalo temp memory)

13
Incident details in: /u01/app/oracle/diag/rdbms/ncdb1/ncdb1/incident/incdir_48332/ncdb1_j001_101922_i48332.trc

14
Use ADRCI or Support Workbench to package the incident.

15
See Note 411.1 at My Oracle Support for error and packaging details.

下面是相关的trace文件的头部的部分信息：

1
*** 2019-06-10 22:12:35.316

2
*** SESSION ID:(650.32147) 2019-06-10 22:12:35.316

3
*** CLIENT ID:() 2019-06-10 22:12:35.316

4
*** SERVICE NAME:(SYS$USERS) 2019-06-10 22:12:35.316

5
*** MODULE NAME:(DBMS_SCHEDULER) 2019-06-10 22:12:35.316

6
*** ACTION NAME:(ORA$AT_SQ_SQL_SW_1803) 2019-06-10 22:12:35.316

通过ACTION NAME部分可用看出来，这是AUTO SQL TUNING触发的错误。下面是触发这个错误的SQL。

001
/* SQL Analyze(650,1) */

002
select SUM(nvl(nnum, 0)) nnum,

003
       SUM(nvl(nmny, 0)) nmny,

004
       datatype,

005
       pk_brsetting

006
  from ((((select sum(nvl(nnum, 0)) nnum,

007
                  sum(nvl(nmny, 0)) nmny,

008
                  'begin' datatype,

009
                  '1001D21000000021WO54' pk_brsetting

010
             from (((select sum(nvl(nabnum, 0)) nnum,

011
                            sum(nvl(nabmny, 0)) nmny

012
                       from ia_periodnab

013
                      where pk_group = '0001A1100000000003Z3'

014
                        and pk_book = '1001A110000000001GQU'

015
                        and pk_org = '1001A110000000001GTH'

016
                        and dr = 0

017
                        and caccountperiod = '2018-12') union

018
                   all((select sum(nvl(ninnum, 0)) nnum,

019
                                sum(nvl(ninmny, 0)) nmny

020
                           from ia_monthin

021
                          where pk_group = '0001A1100000000003Z3'

022
                            and pk_book = '1001A110000000001GQU'

023
                            and pk_org = '1001A110000000001GTH'

024
                            and dr = 0

025
                            and caccountperiod >= '2019-01'

026
                            and caccountperiod <= '2019-04') union all

027
                        (select sum(-nvl(noutnum, 0)) nnum,

028
                                sum(-nvl(noutmny, 0)) nmny

029
                           from ia_monthout

030
                          where pk_group = '0001A1100000000003Z3'

031
                            and pk_book = '1001A110000000001GQU'

032
                            and pk_org = '1001A110000000001GTH'

033
                            and dr = 0

034
                            and caccountperiod >= '2019-01'

035
                            and caccountperiod <= '2019-04')))) a) union all

036
        (select sum(nvl(nnum, 0)) nnum,

037
                  sum(nvl(nmny, 0)) nmny,

038
                  'end' datatype,

039
                  '1001D21000000021WO54' pk_brsetting

040
             from (((select sum(nvl(nabnum, 0)) nnum, sum(nvl(nabmny, 0)) nmny

041
                       from ia_periodnab

042
                      where pk_group = '0001A1100000000003Z3'

043
                        and pk_book = '1001A110000000001GQU'

044
                        and pk_org = '1001A110000000001GTH'

045
                        and dr = 0

046
                        and caccountperiod = '2018-12') union

047
                   all((select sum(nvl(ninnum, 0)) nnum,

048
                                sum(nvl(ninmny, 0)) nmny

049
                           from ia_monthin

050
                          where pk_group = '0001A1100000000003Z3'

051
                            and pk_book = '1001A110000000001GQU'

052
                            and pk_org = '1001A110000000001GTH'

053
                            and dr = 0

054
                            and caccountperiod >= '2019-01'

055
                            and caccountperiod <= '2019-05') union all

056
                        (select sum(-nvl(noutnum, 0)) nnum,

057
                                sum(-nvl(noutmny, 0)) nmny

058
                           from ia_monthout

059
                          where pk_group = '0001A1100000000003Z3'

060
                            and pk_book = '1001A110000000001GQU'

061
                            and pk_org = '1001A110000000001GTH'

062
                            and dr = 0

063
                            and caccountperiod >= '2019-01'

064
                            and caccountperiod <= '2019-05')))) b)) union

065
        all((select sum(nvl(nnum, 0)) nnum,

066
                     sum(nvl(nmny, 0)) nmny,

067
                     'begin' datatype,

068
                     '1001D21000000021WZP4' pk_brsetting

069
                from (((select sum(nvl(nnum, 0)) nnum, sum(nvl(nmny, 0)) nmny

070
                          from ia_goodsledger

071
                         where pk_group = '0001A1100000000003Z3'

072
                           and pk_book = '1001A110000000001GQU'

073
                           and pk_org = '1001A110000000001GTH'

074
                           and dr = 0

075
                           and fintransitflag = 0

076
                           and caccountperiod < '2019-05') union all

077
                      (select sum(-nvl(nnum, 0)) nnum, sum(-nvl(nmny, 0)) nmny

078
                          from ia_goodsledger

079
                         where pk_group = '0001A1100000000003Z3'

080
                           and pk_book = '1001A110000000001GQU'

081
                           and pk_org = '1001A110000000001GTH'

082
                           and dr = 0

083
                           and fintransitflag = 1

084
                           and caccountperiod < '2019-05'))) c) union all

085
             (select sum(nvl(nnum, 0)) nnum,

086
                     sum(nvl(nmny, 0)) nmny,

087
                     'end' datatype,

088
                     '1001D21000000021WZP4' pk_brsetting

089
                from (((select sum(nvl(nnum, 0)) nnum, sum(nvl(nmny, 0)) nmny

090
                          from ia_goodsledger

091
                         where pk_group = '0001A1100000000003Z3'

092
                           and pk_book = '1001A110000000001GQU'

093
                           and pk_org = '1001A110000000001GTH'

094
                           and dr = 0

095
                           and fintransitflag = 0

096
                           and caccountperiod <= '2019-05') union all

097
                      (select sum(-nvl(nnum, 0)) nnum, sum(-nvl(nmny, 0)) nmny

098
                          from ia_goodsledger

099
                         where pk_group = '0001A1100000000003Z3'

100
                           and pk_book = '1001A110000000001GQU'

101
                           and pk_org = '1001A110000000001GTH'

102
                           and dr = 0

103
                           and fintransitflag = 1

104
                           and caccountperiod <= '2019-05'))) d))) union

105
        all((((select sum(nvl(nnum, 0)) nnum,

106
                      sum(nvl(nmny, 0)) nmny,

107
                      'credit' datatype,

108
                      '1001D21000000021WO54' pk_brsetting

109
                 from (select sum(nvl(noutnum, 0)) nnum,

110
                              sum(nvl(noutmny, 0)) nmny

111
                         from ia_monthout

112
                        where pk_group = '0001A1100000000003Z3'

113
                          and pk_book = '1001A110000000001GQU'

114
                          and pk_org = '1001A110000000001GTH'

115
                          and dr = 0

116
                          and caccountperiod >= '2019-05'

117
                          and caccountperiod <= '2019-05') g) union all

118
             (select sum(nvl(nnum, 0)) nnum,

119
                      sum(nvl(nmny, 0)) nmny,

120
                      'debit' datatype,

121
                      '1001D21000000021WO54' pk_brsetting

122
                 from (select sum(nvl(ninnum, 0)) nnum,

123
                              sum(nvl(ninmny, 0)) nmny

124
                         from ia_monthin

125
                        where pk_group = '0001A1100000000003Z3'

126
                          and pk_book = '1001A110000000001GQU'

127
                          and pk_org = '1001A110000000001GTH'

128
                          and dr = 0

129
                          and caccountperiod >= '2019-05'

130
                          and caccountperiod <= '2019-05') h)))) union all

131
        (select sum(nnum) nnum, sum(nmny) nmny, datatype, pk_brsetting

132
           from (((select nvl(nnum, 0) nnum,

133
                          nvl(nmny, 0) nmny,

134
                          case

135
                            when fintransitflag = 0 then

136
                             'debit'

137
                            else

138
                             'credit'

139
                          end datatype,

140
                          '1001D21000000021WZP4' pk_brsetting

141
                     from ia_goodsledger

142
                    where pk_group = '0001A1100000000003Z3'

143
                      and pk_book = '1001A110000000001GQU'

144
                      and pk_org = '1001A110000000001GTH'

145
                      and dr = 0

146
                      and caccountperiod >= '2019-05'

147
                      and caccountperiod <= '2019-05'))) o

148
          group by datatype, pk_brsetting)) s

149
 group by datatype, pk_brsetting

从这里也可用看出这个错误是由AUTO SQL TUNING触发的，这个错误的原因是遇到了单个进程最多只能使用PGA只有4G的限制导致，下面是trace中的相关信息。

01
Dumping Work Area Table (level=1)

02
=====================================

03
 
04
  Global SGA Info

05
  ---------------

06
 
07
    global target:    12856 MB

08
    auto target:       8467 MB

09
    max pga:           2048 MB

10
    pga limit:         4096 MB

11
    pga limit known:  0

12
    pga limit errors:     0

13
 
14
    pga inuse:         3447 MB

15
    pga alloc:         4705 MB

16
    pga freeable:       164 MB

17
    pga freed:        13398681 MB

18
    pga to free:          0 %

19
    broker request:       0

20
 
21
    pga auto:             0 MB

22
    pga manual:           0 MB

23
 
24
    pga alloc  (max):  5882 MB

25
    pga auto   (max):  2084 MB

26
    pga manual (max):     1 MB

27
 
28
    # workareas     :     1

29
    # workareas(max):   106

可用看到，当前的PGA设置是12G，但是单个进程最多只能使用4G，根据MOS文档PLSQL Procedure Causing ORA-04030: (pga heap,control file i/o buffer) And ORA-04030: (koh-kghu sessi,pmuccst: adt/record) or ORA-04030: (koh-kghucall ,pmucalm coll) Errors (文档 ID 1325100.1)的说明，这是因为操作系统默认单个进程最多只能打开65530个内存映射条目限制的。

1
[root@SL010A-NCDB1 ~]# cat /proc/sys/vm/max_map_count

2
65530

数据库也有和这个相对应的隐含参数_realfree_heap_pagesize_hint，默认是65536。

01
SQL> col NAME for a30

02
SQL> col VALUE for a20

03
SQL> col DESCRIB for a45

04
SQL> set lines 200

05
SQL> SELECT x.ksppinm NAME, y.ksppstvl VALUE,x.ksppdesc describ

06
  2  FROM SYS.x$ksppi x, SYS.x$ksppcv y

07
  3  WHERE x.indx = y.indx AND x.ksppinm LIKE '%realfree%';

08
 
09
NAME                           VALUE                DESCRIB

10
------------------------------ -------------------- ---------------------------------------------

11
_realfree_heap_max_size        32768                minimum max total heap size, in Kbytes

12
_realfree_heap_pagesize_hint   65536                hint for real-free page size in bytes

13
_realfree_heap_mode            0                    mode flags for real-free heap

14
_use_realfree_heap             TRUE                 use real-free based allocator for PGA memory

_realfree_heap_pagesize_hin隐含参数的意思是realfree当前的分配大小是65536 bytes，也就是64K，也就对应操作系统上每个内存映射条目的内存大小是64K，而操作系统上又限制每个进程最多能打开65530个内存映射条目，因此，每个进程使用PGA就不能超过4G。

1
SQL> select 65536*65530/1024/1024/1024 GB  from dual;

2
 
3
        GB

4
----------

5
3.99963379

那么对应的就有两种解决方案，一种是调整操作系统单个进程打开内存映射条目的大小，另一种就是在数据库调整对应的分配单元大小。

操作系统调整单个进程打开内存映射条目大小，需要修改sysctl.conf文件，在最下面增加下面这一行即可。

1
[root@SL010A-NCDB1 ~]# vi /etc/sysctl.conf

2
--在最下面增加下面这行

3
vm.max_map_count=262144

然后通过sysctl –p命令使之生效。这样每个映射条目大小64K，262144个条目就是16G，应该足够用了。

或者在数据库调整realfree的分配单元的大小，但是这个隐含参数是静态参数，需要重启数据库才能生效。

1
SQL> alter system set "_realfree_heap_pagesize_hint"=262144 scope=spfile;

2
 
3
System altered.

然后重启数据库，使之生效。

以上两种方法，不管是修改操作系统的限制还是修改数据库的参数，只修改一个就可用，如果两种方法都修改，需要设置合理的值，避免单个进程使用的内存限制过大，万一有个进程出了问题，可能直接就把内存耗尽了。

对本案例来讲，还有一种解决方法，当然只对本案例有效，因为本案例ORA-04030错误是由于AUTO SQL TUNING导致的，而AUTO SQL TUNING对我来讲又没啥用，完全可用通过禁用AUTO SQL TUNING来解决这个问题。可用通过下马的方法关闭AUTO SQL TUNING。

1
BEGIN

2
dbms_auto_task_admin.disable(

3
client_name => 'sql tuning advisor',

4
operation => NULL,

5
window_name => NULL);

6
END;

7
/

如果需要开启AUTO SQL TUNING，可用通过下面的方法来开启。

1
BEGIN

2
dbms_auto_task_admin.enable(

3
client_name => 'sql tuning advisor',

4
operation => NULL,

5
window_name => NULL);

6
END;

7
/

针对单个进程只能使用4G的PGA导致的ORA-04030错误的问题，具体还要看是什么原因导致的，本案例特殊，由于是AUTO SQL TUNING触发的，而AUTO SQL TUNING对我这套数据库来讲并没什么用，所以可用通过禁用AUTO SQL TUNING的方式来解决，如果是业务程序的存储过程等PL/SQL导致的这个错误，就不能这样解决了，只能从上面的修改操作系统单个进程打开内存映射条目数或者修改数据库对应的每个映射条目内存分配大小来解决了。