“Enq: FB contention” is an ASSM enque wich ensures that only one process format the block. This happen usually on parallel inserts on the same table.
June 1, 2012
April 27, 2012
Downgrading 18.104.22.168 to 22.214.171.124 works. But like everything with oracle 11.2 you have to apply a patch.
Oracle Restart (GI) is used for this setup.
# current release
drop user sysman cascade;
# change environment
srvctl downgrade database -d dsdb01 -o /opt/app/oracle/product/11.2.0/rdbms1 -t 126.96.36.199
srvctl modify database -d dsdb01 -p /opt/app/oracle/product/11.2.0/rdbms1/dbs/spfiledsdb01.ora
srvctl config database -d dsdb01
# get cat reload from patch 11811073
August 3, 2011
Actually i go an error ORA-600 [kkoipt:incorrect pwj] on 11.2 an i applied the patch 9929660.
But the error occured on a instance again. So i was wondering how i can check if the online patch is activated.
opatch lsinventory just shows if the patch is installed on the oracle home.
The solution was:
oradebug patch list
Here you see if the patch is activated on the instance. Aswell you could disable the patch for the instance.
April 11, 2011
I hade recently some trouble with Flashback Data Archive (Total Recal, FBDA) on Oracle 188.8.131.52
On a dissasciate Statement like:
Following Oracle error occured:
ORA-00600: internal error code, arguments: [ktfa_get_hist_objn]
The problem was a oracle bug. If you name any column in your table “DATE” – FDBA does not work properly.
November 1, 2010
I am just search since hours for the oracleasm-2.6.32 package … an just coulnd find it.
Now I just came across this pice of information. Maybe it shortens my search 🙂
Be advised that you will have to re-install oracleasm and ocfs2 if you want to revert to the previous PV kernel. Unbreakable Enterprise Kernel itself already includes ocfs2 and oracleasm, so the separate RPMs are not needed.
July 30, 2010
I’ve wrote a simple SQL script to list all ASM disks with state, size and their diskgroups, if any.
set pages 5000 lines 180 set heading on set feedback off set serveroutput on col LABEL for a28 col DISKGROUP for a9 col STATUS for a9 col TOTAL for a11 col MOUNT_STATE for a11 exec dbms_output.put_line('---'); exec dbms_output.put_line('--- DISK OVERVIEW'); exec dbms_output.put_line('---'); SELECT D.LABEL||' ('||D.NAME||')' LABEL, (SELECT NAME FROM V$ASM_DISKGROUP WHERE GROUP_NUMBER=D.GROUP_NUMBER) DISKGROUP, D.STATE STATUS, lpad(D.TOTAL_MB/1024,6)||' GB' TOTAL, D.MOUNT_STATUS MOUNT_STATE FROM V$ASM_DISK D ORDER BY 2; exec dbms_output.put_line('---'); set feedback on
The output looks as follow:
--- --- DISK OVERVIEW --- LABEL DISKGROUP STATUS TOTAL MOUNT_STATE ---------------------------- --------- --------- ----------- ----------- ORAASM1 (ORAASM1) DG1 NORMAL 99.984 GB CACHED ORAASM3 (ORAASM3) DG1 NORMAL 99.984 GB CACHED ORAASM5 (ORAASM5) DG1 NORMAL 99.984 GB CACHED ORAASM4 (ORAASM4) DG1 NORMAL 99.984 GB CACHED ORAASM2 (ORAASM2) FRA1 NORMAL 99.984 GB CACHED ORAASM6 () NORMAL 0 GB CLOSED ---
July 29, 2010
To lock the SGA into physical memory you have to set the lock_sga parameter to true.
Usually you get following Error message.
SQL> ORA-27102: out of memory
Linux-x86_64 Error: 12: Cannot allocate memory
The problem it ulimit -l
You have to set it in /etc/security/limits.conf and relogon to the system and restart database.
oracle soft memlock unlimited
oracle hard memlock unlimited
alter system set lock_sga=true scope=spfile;
And you SGA stays in physical memory.
If you SGA gets pages out you will encounter following waits.
Wait Event: latch: shared pool
July 28, 2010
Enabling and validating constraints is can take a huge amount of time in big oracle databases.
To speed the validaten up, it can be done in parallel.
This can save you valuable time in release windows.
- Enable Constraint with novalidate option
- Set parallel degree on the table or on session with force ddl parallel
- Enable nable the constraints with validation
ALTER TABLE T_1 ADD CONSTRAINT NC_1 not null (colname) disabled;
ALTER TABLE T_1 ENABLE NOVALIDATE CONSTRAINT NC_1;
ALTER SESSION FORCE PARALLEL DDL PARALLEL 8;
ALTER TABLE T_1 PARALLEL 8;
ALTER TABLE T_1 ENABLE VALIDATE CONSTRAINT NC_1;
ALTER SESSION DISABLE PARALLEL DDL;
SQL> startup nomount
ORA-27102: out of memory
Linux-x86_64 Error: 28: No space left on device
There are 64G physical memoray avaliable.
shmmax is set to 52G
But still its not possibel to start the Oracle instance with more than 30G SGA.
kernel.shmall is set to small.
This means that only 8248733 memory pages can be allocate.
4096 x 8248733 = 32G
To allocate 50G we need to set shmall to at least 13107200
July 15, 2010
I tried to run IO calibrate to check what the system is able to handle.
But I run into following error (using ASM / ASMlib)
ORA-56708: Could not find any datafiles with asynchronous i/o capability
ORA-06512: at "SYS.DBMS_RMIN", line 456
ORA-06512: at "SYS.DBMS_RESOURCE_MANAGER", line 1285
ORA-06512: at line 6
The ASM files show ASYNC_ON
SELECT name, asynch_io
FROM v$datafile f,v$iostat_file i
WHERE f.file# = i.file_no
AND filetype_name = 'Data File'
did not help as well
alter system set filesystemio_options=setall scope=spfile;
I guess that the problem is that moste datafiles (smallfiles) are full (max. number of blocks). So the io calibrate tool can not write to this files.
System aio slots:
To find out the maximum avalable asynch I/O slots: $ cat /proc/sys/fs/aio-max-nr 65536 To find out how many are being used: $ cat /proc/sys/fs/aio-nr increase fs.aio-max-nr if nessesary (or restart some db's) 65536