What are the side effects of raising the PROCESSES system parameter

oracle

We have a legacy application (ERP) that, because of technical issues, spawns a new OS process (.exe – ms windows clients) for each screen requested by the user. Also, each company branch (> 20) has its own schema, and the application deals using 1 connection for each. Since each user may open as many screens they deserve to, it is quite common that some users reach > 30 sessions.

That will result in opening many connections to Oracle.
In last report, we got 861 sessions for 87 users (~10 sessions/user).

My customer's DBA is saying that this will knock the database performance down, and demand heaps (really huge amounts) from the server's RAM & CPU.

Does this statement make sense?


So:

  • What are the side effects of raising the PROCESSES system parameter?
  • What is the cost of a open process (even if idle) in the server?

Best Answer

At least it has you have to increase most of the OS kernel parameters(like number of file handles). Most of them have a formula where use PROCESSES is an input. Also each server process allocates some RAM - the about is not big, but when multiplied by one thousand ...

Idle processes do not have any major overhead, but when DB server starts swapping RAM it's over. All the performance is away.