Posted by Just a quick tip today thanks to the one of the readers on my blog. If you’re installing Oracle 12c with the standard database installer, you’re probably used to that moment when the installation is ever so close to finishing and we just need to sync up the installation inventory. You’ll typically see the following screen.
Reader Ernie Kalwa reported some findings which I managed to reproduce, which can be summarised simply as:
The time to save the inventory seems to be proportional the number of files residing under the ORACLE_BASE directory structure.
On my own machine , I’ve long had a standard of having a base directory called “oracle” and having everything under that. Over time that adds up to a lot of versions of various software components 
Conducting a few tests I too found that installing 12c into this existing structure (with the ORACLE_BASE being nominated as C:\ORACLE) yielded several minutes sitting at the “Save Inventory” phase. I then shifted a lot of the directories that would not be impacted/required for the installation to another directory on the same drive but away from C:\ORACLE and the installation ran much quicker, with the inventory phase being just a quick blip and the installation was done!
I could not find any bug references etc to conclusively prove that this is an known issue, but to add my broken record of pontificating about why you should be moving to 19c, I could not reproduce this issue with an 19c installation no matter how many files I had sitting under ORACLE_BASE.
Please let me know if you’re seeing slow inventory times with your software installations and which versions you’re using.
Of course, there are even faster ways of getting up and running with an Oracle database.
Happy installing!
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