Cecilia Grant's Database Performance Tuning Tips

Join Cris and Gavin for a chat about database performance tuning with Cecilia Grant (Architect, Oracle Development). Please review Cecilia's performance tips post on the Exadata blog (link below) ... we bring you the expert, and you bring the questions!

Highlights:

00:11 Welcome
00:43 Blog post http://blogs.oracle.com/exadata/ten-tips-for-database-performance-tuning
00:58 Discussion is about Database Performance everywhere, not just on Exadata
01:39 Gavin introduces Cecilia Grant
02:34 Safe Harbor slide
02:49 The 2-3 most important performance tips
02:57 -- Let the data guide you
03:50 -- Database tuning doesn't change much for Exadata
04:20 -- Keep good baselines
05:09 -- Recap & discussion
06:08 Should you tune performance on Exadata?
06:25 -- "Smart features" let you get away with a lot, but ...
07:01 -- You still need to write good SQL and design schemas properly
07:32 What is a Storage Index - the best I/O is the I/O you don't do
08:19 -- Storage Indexes/Indices are ephemeral - how are they rebuilt?
08:41 -- Conventional Indices/Indexes are still relevant - persistent and less CPU cost
09:19 How do I keep a baseline?
09:52 What is IORM? Should I use it?
09:55 -- IORM is on by default on Exadata
10:09 -- IORM useful to control I/O when hosting multiple databases
10:34 -- Backtrack: IORM defined
11:05 -- Plans and tiers with IORM
11:24 -- Examples of tiers
11:51 I/O outliers on Exadata?
12:13 -- Make sure it's an I/O problem
12:26 -- We expect workload to be distributed evenly
12:59 -- We saw recently a case like that, but...
13:20 -- Normally you reach max capacity on all disks
13:35 -- Apply top tips: use AWR, look at the data
14:15 Where do I find data showing Exadata performance benefits?
14:28 -- Reducing I/O, AWR shows SI savings and CC savings
14:45 -- The SQL monitor report - cell offload efficiency
15:08 -- Comparing to non-Exadata machines
15:33 What about performance on Autonomous DB?
15:50 -- You get an AWR report, but restricted to the PDB
16:12 -- The data you get is ...
16:25 -- Performance tuning?
16:52 -- Concentrate on the upper level / application
17:07 How to architect your data?
17:29 -- Normal forms are good but denormalization may be useful
17:48 -- Beyond the model, look at access patterns
18:01 -- Access patterns, explained
18:34 -- Example: model too complicated
19:24 Persistent Memory (PMEM) in write-through instead of write-back mode?
19:47 -- How it works with flash - write-through
19:58 -- How it works with flash - write-back
20:03 -- How it works with PMEM
20:20 -- Why use write-through with PMEM
20:32 -- -- DB writes are asynchronous, i.e., user doesn't wait for them
20:53 -- How is it different from flash?
21:54 Is the PMEM cache write-through by default?
21:58 New features planned for PMEM?
22:22 -- See also last month's AskTOM on Exadata X8M, with Jia Shi
22:49 -- We used PMEM in the architecturally best manner
23:20 How Cecilia got into performance tuning?
24:13 What it takes to work in performance
25:09 How do the customer experiences connect with our technology design and tuning?
25:30 -- A number of teams bring different facets of experience with the product to dev
26:08 -- Similarly with the Support escalations
26:51 If PMEM is not available, can I still benefit from, e.g., RAM cache features?
27:15 -- Flash speeds v. PMEM speeds
27:34 Websites, whitepapers and other resources?
28:45 Your ideas and questions for topics and experts are welcome
29:00 Do old DB performance methods / tools still apply?
29:27 -- Example recent escalation
31:12 Can Storage Index be stored in Flash cache?
31:28 What can cause increasing logfile parallel writes?
32:17 When is the Storage Index built?
33:09 Storage Index across Storage Servers / Cells
34:00 End remarks

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A monthly opportunity to interact with the Oracle Exadata development experts and technical leadership. Exadata is engineered to deliver dramatically better performance, cost effectiveness, and availability for Oracle databases. Learn how to make the most of Exadata and get your questions answered by Exadata experts!