Estimating Memory Size

[Munish]

Hi All,
We need to estimate the virtual memory size (Scratch) for our project.
Can anyone provide some guideline or best practice to evaluate that.
Do we have any formulas to get those figures.
We are assuming that memory size is decided by
1. Input Data size.
2. Number of stages
3. Number of client accessing server.

Any input will be appreciated.

Thanks and regards,
Munish

[DSguru2B]

Do different levels of search on key words like "memory estimate" or "scratch space estimate". This has been discussed before.

[ray.wurlod]

Do you want to estimate virtual memory requirements or scratch disk requirements? They are not the same things. For example, scratch disk can be used when allocated memory is exceeded, even though there is plenty of free virtual memory - for example in the Sort stage you can limit the amount of virtual memory (by default to 20MB per partition); as soon as this is exceeded then the scratch disk is used. "True" virtual memory, on the other hand, is swapped out to the swap disk when process exchange occurs, and pages out to paging disk when exhausted in the one process. I don't believe you're clear on your terminology.