New Linux-MM homepage

New Linux-MM homepage

[Rik van Riel]

Hi,

I've written a new, more structured and more complete
Linux MM homepage. It's not finished yet, but I need
the input of you guys to make it better...

You can find it on:  <http://www.phys.uu.nl/~riel/mm-patch/>

TIA for suggestions,

Rik.
+-------------------------------------------------------------------+
| Linux memory management tour guide.        H.H.vanRiel@phys.uu.nl |
| Scouting Vries cubscout leader.      http://www.phys.uu.nl/~riel/ |
+-------------------------------------------------------------------+

Re: New Linux-MM homepage

[Eric W. Biederman]

>>>>> "RR" == Rik van Riel <H.H.vanRiel@phys.uu.nl> writes:

RR> Hi,
RR> I've written a new, more structured and more complete
RR> Linux MM homepage. It's not finished yet, but I need
RR> the input of you guys to make it better...

RR> You can find it on:  <http://www.phys.uu.nl/~riel/mm-patch/>

RR> TIA for suggestions,

 * The current code also has some small bugs regarding page aging and administration of
   shared pages; they are scanned multiple times and we sometimes loose track of them. ->
   Vnodes & shmfs.

Q: We loose track of shared pages?  I'm not aware of this, could I get
a better description.

Suggestion:
We might possibly want to include on the developers page everyone's
email address, and then on the suggestions page just link back to the
developers page...

Also,
Thanks for writing documentation.  I am really bad at doing that.

Eric

Re: New Linux-MM homepage

[Rik van Riel]

On 19 Jun 1998, Eric W. Biederman wrote:
> >>>>> "RR" == Rik van Riel <H.H.vanRiel@phys.uu.nl> writes:
> 
> RR> You can find it on:  <http://www.phys.uu.nl/~riel/mm-patch/>
> 
>  * The current code also has some small bugs regarding page aging and administration of
>    shared pages; they are scanned multiple times and we sometimes loose track of them. ->
>    Vnodes & shmfs.
> 
> Q: We loose track of shared pages?  I'm not aware of this, could I get
> a better description.

Well, there are several cases where we 'forget' about
shared area's. One of them is where SysV shared memory
is unmapped from all processes but the handle remains.
Since we do page scanning by process, we can't find
such an area. I don't know if this has been fixed by
now, but I certainly remember the messages about it...

> Suggestion:
> We might possibly want to include on the developers page everyone's
> email address, and then on the suggestions page just link back to the
> developers page...

OK, I'll do that.

> Thanks for writing documentation.  I am really bad at doing that.

"To teach is to learn twice" I'm not a very productive
programmer yet, I don't even do a CS study. By writing
docs, I get to think about things more and as a result
I am becoming a better programmer.

Also, I really like it when people can actually use
the code we're writing. We don't _just_ write it for
fun...

Rik.
+-------------------------------------------------------------------+
| Linux memory management tour guide.        H.H.vanRiel@phys.uu.nl |
| Scouting Vries cubscout leader.      http://www.phys.uu.nl/~riel/ |
+-------------------------------------------------------------------+

Re: New Linux-MM homepage

[Eric W. Biederman]

>>>>> "RR" == Rik van Riel <H.H.vanRiel@phys.uu.nl> writes:

RR> On 19 Jun 1998, Eric W. Biederman wrote:

RR> Well, there are several cases where we 'forget' about
RR> shared area's. One of them is where SysV shared memory
RR> is unmapped from all processes but the handle remains.
RR> Since we do page scanning by process, we can't find
RR> such an area. I don't know if this has been fixed by
RR> now, but I certainly remember the messages about it...

I hadn't quite categorized it that way.  
But I both discovered the problem and have posted a fix to linux-mm
that should work.

So for that case of swapoff we are fine.  Or should be soon :)
Now if there are any other cases I don't know about.

I was afraid you were talking about a memory leak...

Eric