Jet engine and multiple processors

[Rod]

Does Access and in particular the Jet engine make use of multiple processors
in any version of Office?

If yes, does it know to distinguish between physical and logical processors?


many thanks

Rod

 

[Douglas J. Steele]

As far as I'm aware, no version of Access has ever made use of multiple
processors.

 

[david]

Windows normally puts multiple threads from the same
program onto the same processor. Processor Affinity
gives better cache behaviour when you are running
multiple different tasks.

This approach is optimal for a workstation, because it
gives you good UI response, and allows the computer to continue
with other tasks.

Obviously, it is not optimal for a dedicated database
server, but it is a deliberate design decision for Windows
(workstation) and Office.

The Jet engine is multi-threaded. All the threads will
run on one processor.

 

[Rod]

Seems that if I spash out on a multi-core machine I would be wasting my
money.
I may do two things at once, but that leaves 4 cores twiddling their digits.

 

[david]

Multi-processor is huge in the server and calculation
markets. It is worth paying for in the home video
processing market, which is a calculation task.

It is less convincing in the office PC market.

Still, people use to love Dual Pentium Pro workstations,
because it let them get on with their life while downloading
mail or some other slow task.

I certainly would not pay for hyper-threading on a
workstation, that has no place on a workstation, as
lots of people have discovered.

Linux uses a different thread affinity algorithm. MS might
change as more cores become more common. I wouldn't
like to predict the future, except to say the MS already
has a database product which scales across multiple cores
-- I don't see them changing Access/Jet to cannibalize that
market.

(david)

 

[vanderghast]

Disk IO may be preformed by another CPU, since the Kernel mode is likely to
kick in... but that matters only if the db is local.


Vanderghast, Access MVP