xerosaburu wrote:What "part" would you think does it?
I've been doing this for years, but I don't know the answer to this question.
xerosaburu wrote:I understand that. What is NOT apparent from you post is just what you consider a "part". A background process like dbwr, pmon, smon, etc? Or something else?
Oracle architecture is complex and often you read in the documentation that "Oracle" does this and "Oracle" does that, later you find out that a component of Oracle did this or did that and that these components had subcomponents all the way down the rabbit hole.
I want to go down that rabbit hole on this.
Edited by: xerosaburu on Dec 12, 2012 6:48 AM
xerosaburu wrote:Sounds like you are talking about
Before the pmon starts, something else has to happen to boot the whole thing.
I think it's the oraspawn.dll in windows, but I'm not sure what "things" exist to get things going in linux.
However I don't know where that gets you or whether your next question will be What spawns the process spawner process?
PSP0 Process Spawner Spawns Oracle background processes Process after initial instance startup
xerosaburu wrote:I'd guess it is probably built into the kernel, or very close to it, in the code that implements the 'startup' command.
We know that the background processes can't start until the parameter file is read, so the initial post was asking about what "part" (using the term "part" as a variable) or "parts" precede in the logical chain.
xerosaburu wrote:I would probably guess that this means sqlplus "bequeaths" a server process, which on win platform is a thread of oracle.exe, which, when acting on startup command, reads the spfile and creates the pmon process which continues to start the instance (remaining background processes/threads and memory areas).
... sqlplus.exe loads the oraspawn.dll and itself appears to boot the process, whereafter the oracle.exe itself reads the parameter file, and then creates the memory structures and background processes.