Advice on Oracle RAC

[Andrew Young_2]

Hi All.

I'm busy designing an Oracle 10G RAC solution for a tiny telco and was wondering at what sort of level of transaction load (or any other criteria) I would need to start using an Infiniband interlink instead of Gigabit Ethernet?

Your wisdom in this regard would be appreciated.

Regards

Andrew Y

[Ivan Ferreira]

Telco normally requiere very small delay in their transactions, independently of the volume of them.

Considering the availability of the technology, and the possible future requirements, I would go for infiniband.

[Steven E. Protter]

Shalom Andrew,

The bigger the pipe the better.

Oracle 10G RAC is not a thin client. It's a thick one and it will benefit greatly from a large pipe, particularly if you plan to use dataguard to replicate data to a DR site or backup site.

Response time needs to be very good, so overdesign the server and make sure the disk is set up as fast as possible. Redo, index and data should be raid 1 or raid 10, not raid 5 as this slows down write intensive databases.

SEP

[Andrew Young_2]

Hi Steve and Ivan

Thanks for your responses.

The client is tiny. They have an installed base of 50000 lines and that includes leased data lines. The client currently runs on Alpha ES40's with Oracle 8i, data to and from the exchanges is batched every hour using dblinks and daily to the remote payment stations (they use Oracle PE) via good old dialup. Their production database is 65Gb or less and that includes month-to-date transaction data, 5 years transaction history is estimated at 350 Gb in a seperate database. Online queries and capturing use Oracle Forms client server running on a DL360 citrix server and WSYE (Windows CE) thin clients. There are +- 190 users, with no concurrent database connections. Realistically only two thirds of the users are regular users.

The idea is to replace the forms with Oracle 10G AS R2 but their budget is really tight with essentialy 1 000 000 USD to do the hardware refresh, database upgrade and the conversion to Application Server(300 forms and 350 reports). There is also a small development environment to cater for.

Essentially their current requirements can easilly be met using dual core rx2660's and a small 2C2D EVA4000 for the database so somehow putting in two AD313A Infiniband adaptors and two 24 port Infiniband switches seems overkill.

So my question really is at what load level do I need to get worried that Gigabit Ethernet is not going to be sufficient to manage their requirements. Are there any other alternatives?

Regards

Andrew Y

[Steve Lewis · Accepted solution]

Andrew,

Whilst Infiniband is itself a very low latency technology all the manufacturers put a tcp/ip stack on top of it, which nullifies some of the benefits.

With the size of your system I think you will be fine with a 1gig copper ethernet card provided you enable the special features in the latest drivers,

checksum offload;
tcp segmentation offload.

See the latest lanadmin man page for details of these.
You can also increase the tcp send/recv windows.

Another option to consider instead of infiniband is 10Gb Ethernet.

A third option to consider is APA.

[Andrew Young_2]

Thanks for everyones input.

Regards

Andrew Y

[Andrew Young_2]

thx