Re: Pro*C Size/Speed issues

Jennifer R. Amon (bamon_at_ocvaxc.cc.oberlin.edu) wrote:
> Hi,
 

> Platform: VAX/VMS v5.5-2, VAX C
> Oracle RDBMS 7.0.15.4
> Pro*C 1.5.6.2.0
 

> I've got a Pro*C program. It was a C program, to which I added only
> as much as necessary to logon to Oracle. There will be much more to
> come later, but for now, it just logs on. The .exe jumped from 171
> blocks to 1735 blocks. The whole program slowed down, probably due
> to page faulting.

The extra size is for all the Oracle libraries. They're statically linked into the executable. Good isn't it?

> What are my options now? What is the extra size, a map of the SGA?
> Note: on a machine with a considerably smaller SGA, the executable
> is only 797 blocks.

I didn't think the SGA was that big. I've never checked though.

> For example, I'm using dynamic memory allocation to deal with data
> that's coming in from flat files. Would I be any better off if I
> pre-allocate a large static array?

I managed to improve performance of my code by moving frequently accessed reference tables from the database into memory, which means I can then access it using a binary search rather than a SELECT and waiting for the DBMS to supply results.

The side-effect of this is that I need to lock the tables which I cached in memory (to ensure read consistancy). This located a bug in Forms (users not getting a "Attempt to lock record failed: Retry/Cancel" messages).

And so it goes.

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