Seeing Exadata in action 9

Last week I was able to attend a 3 day exadata workshop conducted by performance engineers from Singapore. It was supposed to be a 5 day workshop with hands on labs but everything was squeezed (unfortunately no hands on) and just the critical sections were tackled.. The workshop highlight was the demos and these are as follows:

– loading large amount of data from an external table
– cell offloading on a typical datawarehouse query
– creation of a 400gb tablespace
– linear scalability of storage cells

Although all of these demos were done on Exadata Version 1.. and just 13 of the storage servers were running..I can say that the performance is still stunning!!!


RAC system load testing and test plan 3

Yesterday I was browsing through some docs in Metalink regarding RAC on Windows… then again came across the “RAC Starter Kit and Best Practices” notes…

RAC Assurance Support Team: RAC Starter Kit and Best Practices (Generic) (Doc ID 810394.1)
RAC Assurance Support Team: RAC Starter Kit and Best Practices (Windows) (Doc ID 811271.1)


Diagnosing and Resolving “gc block lost” 34

Last week, one of our clients had a sudden slow down on all of their applications which is running on two node RAC environment

Below is the summary of the setup:
– Server and Storage: SunFire X4200 with LUNs on EMC CX300
– OS: RHEL 4.3 ES
– Oracle (database and clusterware)
– Database Files, Flash Recovery Area, OCR, and Voting disk are located on OCFS2 filesystems
– Application: Forms and Reports (6i and also lower)

As per the DBA, the workload on the database was normal and there were no changes on the RAC nodes and on the applications. Hmm, I can’t really tell because I haven’t really looked into their workload so I don’t have past data to compare.