Here I’ll describe some strange/interesting/ behaviour of Global Application Context connected with usage of Session Client Identifier, that is quite usually met in Application Express, J2EE Agent, Oracle Data Integrator starting from release 184.108.40.206 and many other applications that uses JDBC Connection Pooling in conjunction with setting Session Client Identifier.
So what is the problem ?
The problem is that Global Application Context doesn’t work as expected and described in documentation – attributes’ VALUES ARE NOT VISIBLE… (more…)
Oracle RDBMS PatchSet version 220.127.116.11 is available for downloading since 27-AUG-2013 ! again some time earlier than OOW2013
But(as of 29-AUG-2013) it’s still available only for Linux x86-64 + Linux x86 and all Oracle Solarises(x86, x86-64, SPARC 32-bit, SPARC 64-bit)
Checked on 29-OCT-2013 – patchset aditionally available for next platforms: Microsoft Windows(32-bit), Microsoft Windows x64(64-bit), HP-UX Itanium(32-bit), HP-UX Itanium(64-bit), IBM AIX on POWER Systems (32-bit), IBM AIX on POWER Systems (64-bit)
Based on NOTE:742060.1 Release Schedule of Current Database Releases:
18.104.22.168 on Linux x66(new platform ? ;)) released – this joke no more present in mentioned document ;-)
- this is the terminal patch set for 11.2 (more…)
Today I was contacted by one of our customers with very non-typical issue on their 10.2.0.4 database. They have added new column to one table at the middle of the day and now they are not able to compile some of invalidated packages.
Now I’m clarifying what does it mean ‘NOT ABLE TO COMPILE‘:
ALTER PACKAGE PKG_ERP_MAIN COMPILE;
ALTER PACKAGE PKG_ERP_MAIN COMPILE BODY;
Package body altered.
select object_type,status from dba_objects where object_name='PKG_ERP_MAIN';
PACKAGE BODY INVALID
Funny! Isn’t ? (more…)
I have faced quite interesting situation with Flashback Data Archive(FBDA) that wasn’t covered yet in blogosphere.
So I have just created new Flashback Archive and altered some tables specifying it(Flashback Archive).
Just after some time of any DMLs on altered tables next error appears in alert.log
Starting background process FBDA
Thu Feb 21 11:07:07 2013
FBDA started with pid=203, OS id=3626
Errors in file /u01/app/oracle/diag/rdbms/siam_opt/siamopt/trace/orcl_fbda_3626.trc (incident=57628):
ORA-00600: internal error code, arguments: [ktfa_error_handler_map], , 
ORA-00942: table or view does not exist
Please, notice presence of additional funny error – ORA-00942. Why it may be here ? we’ll see later… (more…)
Just short post about Something Coming Soon from mentioned note
Modified:Jan 23, 2013
COMING SOON!!! Stay Tuned
Still have to wait ;)
Despite the fact that there were some speculations that Oracle Database 12c will be released on 12.12.(20)12 to use the Magic of 3×12, this opportunity was missed by Oracle and Release 12c is still in Beta Testing period,
so we have to wait for the another ‘good’ moment like 3×13(12.13.13) ;)
Later we’ll see if it add more power to new Release… ;)
I have been contacted by one of our customers to provide reference information on troubleshooting Oracle Log File Sync waits.
I think that this information worth short blog post.
- Log File Sync waits occur when sessions wait for redo data to be written to disk
- typically this is caused by slow writes(IO subsystem saturation,…)
- spikes in Log File Parallel Write, as shown by James Morle
- or the application is committing too frequently
- improper Operating System configuration(check 169706.1)
- CPU overburning(very high demand => LGWR on run queue, check Kevin Closson post)
- high Log Parallelism, which saturates filesystem/OS, as investigated by Nikolay Savvinov
- BUGs in Oracle(especially with RAC option) and 3rd Party software(like ODM/DISM)
Recently I was involved in performance troubleshooting of one quite expensive system
that had performance problems during business hours.
I’ll not provide all details, but just post some pictures that will show resource usage:
Oracle memory allocation:
Linux memory allocation
or from other side:
MemTotal: 98848220 kB
MemFree: 75109972 kB
Buffers: 597460 kB