After reading my earlier post on shared pool A stroll through shared pool heap , one of my client contacted me with an interesting ORA-4031 issue. Client was getting ORA-4031 errors and shared pool size was over 4GB ( in a RAC environment). Client DBA queried v$sgastat to show that there is plenty of free memory in the shared pool. We researched the issue and it is worth blogging. Client DBA was confused as to how there can be ORA-4031 errors when the shared pool free memory is few GBs.
At this point, it is imperative to take heapdump in level 2 and Level 2 is for the shared pool heap dump. [ Please be warned that it is not advisable to take shared pool heap dumps excessively, as that itself can cause performance issue. During an offline conversation, Tanel Poder said that heapdump can freeze instance as his clients have experienced.]. This will create a trace file in user_dump_dest destination and that trace file is quite useful in analyzing the contents of shared pool heap. Tanel Poder has an excellent script heapdump_analyzer . I modified that script adding code for aggregation at hea, extent and type levels to debug this issue further and it is available as heapdump_dissect.ksh . ( with a special permission from Tanel to publish this script.)
Shared pool review
I get to see a lot of "in house" applications - those applications developed internally for and by a company itself.
The screens on these applications many times have more fields on them than the mind can fathom. Fields and buttons galore.
Just like this cartoon demonstrates...
It is so true - I like simple user interfaces (yes, I'm a metalink classic fan too...)
Every now and then, you read something that makes you go "huh".
I was answering some questions on asktom today and had one about a CSV (comma separated values) file. Thought I would point the person to the 'specification' for that file format and the first searching I did turned this up (from a forum)
Perhaps I misunderstand the question because I'm not sure what
"format" and "escape" characters are.
However, to my knowledge, CSV files are nothing more than ascii text
files, which means the font is courier and 12 pt.
The emphasis is mine - a CSV file is just a file where the text is in 12pt courier! That is so simple.
Sometimes, you read something and it just makes you laugh out loud...