Re: libpager

[Brent W. Baccala]

On Sun, Aug 6, 2017 at 12:40 PM, Justus Winter <justus@gnupg.org> wrote:

"Brent W. Baccala" <cosine@freesoft.org> writes:

> but it's obviously got some issues

What kind of issues?

I was thinking of a multi-client environment where a disk-backed pager is also doing non-disk-backed (i.e, cache coherency) operations.  One client is trying to page in from the disk while two other clients (with write access) are passing a page back and forth between themselves with no disk operations required.  The clients doing non-disk stuff would have to wait for the disk operations to complete.  Now that I think about it more, I admit that it's a bit of a stretch.

 

> and could become a performance bottleneck at some point.  There's no
> good reason to block all access to page 100 while a disk operation
> completes on page 1.

Let's wait until it actually becomes a bottleneck...

Yes, I agree.

 

Are you aware of the pager rework in [0]?  I'm considering to review and
merge these changes.  It may make sense to try to come up with a common
API.  What is the state of your library, is it a drop-in replacement?

0: https://git.sceen.net/hurd/hurd.git/log/?h=mplaneta/gsoc12/review_v1

I was not aware of this link, exactly.  Richard Braun mentioned a GSoC 12 project a week ago, but I thought that it was a gnumach modification.  Glancing at this git repository, I see that it's all translator stuff.  I'll study it.  Is there corresponding gnumach work?

The state of my library is that it's in pseudo code.  It's intended to be a drop-in replacement for libpager.

    agape

    brent