Pageable code

NTDEV
1

I’ve seen a lot of people write this recently. I’d like to remind you that
virtualization is happening in a big way, and that while the amount of
pageable code in your driver may be relatively small compared to the RAM in
the system, that amount is starting to be multiplied by the number of VMs
running on the system. We’re seeing lots of customers who want their VMs to
use as little memory as possible and small RAM images are becoming a lot
more common that they were even a couple of years ago.

–
Jake Oshins
Hyper-V I/O Architect
Windows Kernel Team

This post implies no warranties and confers no rights.

“Tim Roberts” wrote in message news:xxxxx@ntdev…
> At the risk of committing sacrilege, I would assert that worrying about
> paged memory in a driver is silly unless you have an unusually large
> driver. If all of the code in your driver fits in 32k bytes (as many
> do), then it is ridiculous to spend any time at all worrying about
> paging. Just remove all of the “#pragma code_seg()” statements
> completely.
>
> –
> Tim Roberts, xxxxx@probo.com
> Providenza & Boekelheide, Inc.
>
>

2

Jake Oshins wrote:

I’ve seen a lot of people write this recently. I’d like to remind you
that virtualization is happening in a big way, and that while the
amount of pageable code in your driver may be relatively small
compared to the RAM in the system, that amount is starting to be
multiplied by the number of VMs running on the system. We’re seeing
lots of customers who want their VMs to use as little memory as
possible and small RAM images are becoming a lot more common that they
were even a couple of years ago.

Yes, that’s an excellent point, and once you learn the rules, it’s not
that hard to Do The Right Thing. On the other hand, you’d have to have
256 copies of a 32kB driver before the cost of the memory it consumes
rises to $0.01.

–
Tim Roberts, xxxxx@probo.com
Providenza & Boekelheide, Inc.