12C first experience

[cmmrfrds]

Hi Dave, my company is in the process of upgrading to Oracle 12C and we are testing now. The environment is 12 CPU AIX Unix OS running 4 virtual Oracle Servers. We have installed 12C on one of the virtual servers. Each instance has 250 gigs of memory shared 70 for the OS and 180 for Oracle. The application is a data warehouse with 12 terabytes of data. We will upgrade our production system when the testing is complete. Also, most queries are scheduled from a Business Objects application. In addition, a data management tool called Meta Miner that captures information on the scheduled instances including run times. In our typical upgrades we run a test instance of Business Objects and Meta Miner, which allows us to compare the run times of the test instances with the production instances.

On our first tests we have run into memory problems that the DBA is working on along with the Unix admins. This is impacting our ability to get good test runs. Since I work on the application side, I am familiarizing myself with the difference in the Explain Plans between 11 and 12C. The first thing I notice is that it is taking longer to compile the explain plans in 12C. Some of the queries are quite large and complex, so as an example a plan that is taking 5 seconds in 11 is taking 5 minutes in 12C. Most of the times are closer, but there are some extreme examples. Once we get the memory problem worked out I will be able to proceed.

I am excited to get the testing done, so I can look into some of the new features of 12C. What new features do you recommend and have the most impact on throughput.

 

[SantaMufasa]

cmmrfrds, I'm sorry for the delay in responding...I've been buried with company work lately, and it's really impaired my ability to get onto Tek-Tips.

I feel your pain with 12C implementation. I highly recommend logging a defect on Oracle Metalink (if you haven't done so already). Having one of Oracle's people on the hook to solve the problem is probably the quickest way to get it resolved.

Please do update this thread with the resolution to your need.

Best regards,

Mufasa
(aka Dave of Sandy, Utah, USA)
ôPeople may forget what you say, but they will never forget how you made them feel.

 

[cmmrfrds]

Hi Dave. We did upgrade to 12C but kept the 11G optimizer since we didn't eliminate all the problems with our queries. The 11G optimizer works okay in 12C and our DBA wants to wait until 12C release 2 before we run any more tests with the 12C optimizer.

One of the things we want to do shortly is do a POC on the in-memory features of 12C. Do you have any experience you can share on the in-memory option.

Thank you,
Jerry