Skip to main content

UKOUG Tech15 is over, looking forward to Tech16

What a busy week! The UKOUG Tech15 conference made me busy for four days, postponing any other work and non work stuff.
As usual, I met many people actually using our products - it's always a bit strange feeling and a strong confirmation seeing people trusting their data and apps to something a developer writes:-)
And of course, seeing many old friends again was also very nice. Especially talking to Gluent guys (http://gluent.com) and seeing what they are up to was very interesting and promising - I hope they succeed in a big way and change the data landscape.

And of course, the Twinkies...

Comments

Popular posts from this blog

ORA-27048: skgfifi: file header information is invalid

I was asked to analyze a situation, when an attempt to recover a 11g (standby) database resulted in bunch of "ORA-27048: skgfifi: file header information is invalid" errors.

I tried to reproduce the error on my test system, using different versions (EE, SE, 11.1.0.6, 11.1.0.7), but to no avail. Fortunately, I finally got to the failing system:

SQL> recover standby database;
ORA-00279: change 9614132 generated at 11/27/2009 17:59:06 needed for thread 1
ORA-00289: suggestion :
/u01/flash_recovery_area/T1/archivelog/2009_11_27/o1_mf_1_208_%u_.arc
ORA-27048: skgfifi: file header information is invalid
ORA-27048: skgfifi: file header information is invalid
ORA-27048: skgfifi: file header information is invalid
ORA-27048: skgfifi: file header information is invalid
ORA-27048: skgfifi: file header information is invalid
ORA-27048: skgfifi: file header information is invalid
ORA-00280: change 9614132 for thread 1 is in sequence #208


Interestingly, nothing interesting is written to alert.log n…

Reading data from PGA and SGA

Overview For our investigation of execution plan as it is stored in memory, we need in the first place to be able to read the memory.

We have the options of
x$ksmmem, reading SGA using SQL. Personally I don't like it, it's cumbersome and slow.direct SGA read: obviously reading SGA only; it's fast and easy to doread process memory: can read PGA, process stack - and since the processes do map the SGA, too, you can read it as well. Unfortunately ptrace sends signals to the processes and the process is paused when reading it, but so far all my reads were short and fast and the processes did not notice. Some OS configurations can prevent you from using ptrace (e.g. docker by default), google for CAP_SYS_PTRACE.gdb: using your favorite debugger, you can read memory as well. Useful when investigating. Direct SGA read I always considered direct SGA read of some dark magic, but the fundamentals are actually very easy. It still looks like sorcery when actually reading the Oracle in…

A few thoughts about OCM 12c upgrade

Yesterday I sat for the 12c OCM upgrade exam, which I mentioned in few blog posts before. The first step after checking your ID is of course signing the NDA, and thus you won't find much real information here.

This time I chose Utrecht as the place to take the exam. Not that I have any special preference, I took each of the exams in a different place so far. The only requirements were convenient time and location defined as 'somewhere in Europe'. But in the end, Utrecht turned out to be a good place. Oracle NL headquarters are easy accessible, it's a very new building, the lunch was good:-)
And the city is nice to see.

Regarding the exam, the usual important notes still hold true:

Arrive on time. It's a long day and you will have a lot of things to do.You will work hard the whole day. Get a good sleep before, be well rested.Review the exam topics well. Note that they may have change over time. There is for example an update as of January 1, 2016: Flex ASM was added…