How Many Concurrent Users For Oracle Database? This is to analyse and get perfect result for How many concurrent use

[rajeshprasath 0]

Hi friends,

How many concurrent users can practically access the oracle database?

they say tht the figure is hundreds of thousands users...is there any exact figure?

or does the number of concurrent users depend on any other factors as wel?

 

I think depend on parameter

1.session

2.processes

 

session

Specific connection of a user to an Oracle instance through a user process. A session lasts from the time the user connects until the time the user disconnects or exits the database application.

 

Multiple sessions can be created and exist concurrently for a single Oracle user using the same user name. For example, a user with the user name/password of SCOTT/TIGER can connect to the same Oracle instance several times.

 

In configurations without the shared server, Oracle creates a server process on behalf of each user session. However, with the shared server, many user sessions can share a single server process.

 

So please clarify my doubsts.........

 

Regards

Rajeshprasath.T

[yordan 10]

The biggest Oracle system currently tested (with a huge AIX machine) performs three million transactions per minute. I don't know if you really realize what this means. In order to sustain such an amount of users concurrently perform transactions, the system mainly needs a lot of CPU power (64 procesors on the same motherboard). But the system also needs a lot of disks, because the transactions have to be written on disks. Do you know how many disks need to be used, in order that the system never has towait for the disks : several tousands of disks !Of course, Oracle hasto be fine-tuned in order to perform this. Have a look a the tuning guides at technet.oracle.com Of course you have to tune sessions, processes. And a lot of other parameters : if you allow enough sga (system global area) and enough pga (private global area), each user will use a lot of memory and the response times will be short. If each user has less memory, more disk usage will slow down the performances. If each user has enough memory, the total system usage will be greater thant the physical system memory, and swapping will occur, and response time will become disk response time instead of memory response time, so performances will be about one hundred times worse.So, tuning an Oracle database is a nice game, where you have a lot of resource tu tune, according essentially to the money you have : if you buy less disk, you will be slower ; if you buy less memory, you will be slower ; if you have enough disks and memory, you will have to buy more cpu's in order to go faster. So, the real game will be to achieve the exact degree of performances you want (how many users doing how many things in how much time) for the exact money you have : if you buy too much hardware you loose your money, if you don't buy enough material you don't reach your performances. Of course, your questions was about the ultimate Oracle database performances. These performance are also obtained on the ultimate system, where the database system is a small part of a big thing (involving the web servers and the application servers providing service for the customers), whe whole thing being several million dollars worth...A nice job, a nice dream, a long experience needed, and of course not each detail will be explained here in five minutes while wathing my movie on the TV...RegardsYordan