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Oracle database and grid home patches to install

This blogpost is about Oracle database and grid infrastructure software homes, which patches should be applied to which homes, and what it then looks like. This is fully documented by MyOracleSupport notes, but you will see that with version 18 and up this is unclear.

I keep a script-set that automatically installs and patches the Oracle database software and creates a database. This script-set is called vagrant-builder, and it can install any version with any PSU applied between 11.2.0.2 up to 19.5, which is the latest PSU of the latest version, with a few exceptions: for 11.2.0.2 and 11.2.0.3 I only created an install for the base version and the latest PSU for the database, and version 12.1.0.1 is left out entirely.

Oracle internal data dictionary oddity

This blogpost is about an inconsistency I found in the X$ tables X$KQFTA and X$KQFCO. This is very specific. If you don’t care about that, you can skip this post.

The Oracle database’s “dynamic performance views” are views that are prefixed with “GV$” and “V$”. The “G” with “GV$” stands for “global” and gets you the results from its “V$” equivalent for all instances. In most cases, but that’s not the purpose of this blog. In most cases, the “V$” version simply is the “GV$” view with inst_id (instance id, used in RAC to specify the instance id) set to the current instance. I’ll refer to both simply as “V$” for simplicity.

The “V$” views are mostly build on top of “X$” tables. The “X$” tables are Oracle internal tables, and not officially supported, therefore you should use the “V$” views.

What’s new with Oracle database 18.8 versus 18.7

The amount of changes between version 18.7 and 18.8 is truly minimal. There’s one spare parameter renamed to an underscore parameter, which seems to be a back port of functionality created version 19:

What’s new with Oracle database 19.5 versus 19.4

It seems that the most eye-catching difference between Oracle database versions 19.5 and 19.4 is three underscore parameters spare parameters being changed to specifically named underscore parameters, two of them have a bug number in them which is not publicly visible.

In v$sysstat/v$sesstat, a group of statistics are renamed from ‘OS %’ to ‘Server %’. All these statistics are about networking. One changed parameter directly points to networking (tcpinfo). These statistics are added in version 19.

One DBA view was added: DBA_DV_COMMON_OPERATION_STATUS. This view is specific and owned by to DVSYS.

Oracle memory troubleshooting using analysis on heapdumps, part 2

In the article oracle memory troubleshooting using analysis on heap dumps I introduced heap_analyze.awk.

The reason the tool exists is because I am using it myself. Therefore, I ran into additional things that I wanted the tool to do. I added some stuff, which is that significant, that I decided to make another blogpost to introduce the new features.

1. Percentages
In order to get an idea of the relative size of the summarised topic, I added a percentage. For example:

Oracle memory troubleshooting using analysis on heapdumps

This blogpost is about analysing Oracle heap dumps. It is an extension to earlier work, Tanel Poder’s heap dump analyzer. So hat tip to Tanel, he’s done the hard work, I merely increased the presentation options. The heap analyser script that I wrote analyses Oracle heapdumps from the trace file that the dump was written to by the Oracle database. Because the heap dump representation is the same between PGA and SGA memory, it can work on both. The reason for this is that memory management is done by the same memory manager, and is commonly called ‘kgh’ (kernel generic heap) managed memory.

Please mind that for PGA analysis, not all memory is managed by the kgh memory manager. For example memory used for networking (sqlnet) is allocated totally outside of the kgh memory manager.

What’s new with Oracle database 19.4 versus 19.3

The most notable thing here is an “official” (non-underscore) parameter has been introduced with 19.4, “ignore_session_set_param_errors”. The description is: ‘Ignore errors during alter session param set’. I did a quick check to see if I could set it to true or false, which I couldn’t (resulted in an error).

With the Oracle database version 19.3 patched to 19.4 on linux, the following things have changed:

What’s new with Oracle database 18.7 versus 18.6

With the Oracle database version 18.6 patched to 18.7 on linux, the following things have changed:

What’s new with Oracle database 12.2.0.1.190416 versus 12.2.0.1.190716

There are a couple of underscore parameters changed from spare to named ones.
It’s interesting to see that in sysstat, ‘spare statistic 2’ changed to ‘cell XT granule IO bytes saved by HDFS tbs extent map scan’. This obviously has to do with big data access via cell servers. What is weird is that this is the only version where this had happened.

What’s new with Oracle database 12.1.0.2.190416 versus 12.1.0.2.190716

There are a couple of undocumented spare parameters changed to named undocumented parameters, this is quite normal to see.

With the Oracle database version 12.1.0.2.190416 patched to 12.1.0.2.190716 on linux, the following things have changed: