Using zones in NTOS

[Aliberti Emanuele]

What are the advantages in using zones when allocating memory in kernel 
mode?
Are there other ways to pre-allocate an address range to be used for 
small memory objects management (NP pool)?

Emanuele

[KJK::Hyperion]

At 14.48 23/10/2004, you wrote:
>  What are the advantages in using zones when allocating
> memory in kernel mode? 
I assume you use "zone" as the old word for "lookaside lists". Since
there 
only are two possible kernel-mode pools vs infinite user-mode heaps, they 
are a way to have a sort of specialized "private heap" for frequent, small 
allocations (like IRPs and MDLs). They spare you frequent calls to the 
heavier (and globally locking - I don't know if reentrancy issues allow you 
to have a lock-free implementation) pool allocator

>  Are there other ways to pre-allocate an address range
> to be used for small 
> memory objects management (NP pool)? 
Aside from rolling your own, no. Lookaside lists would still have the 
advantage of being traced and profiled

[Aliberti Emanuele]

KJK::Hyperion wrote:

>   Are there other ways to pre-allocate an address range
> to be used for 
>  small memory objects management (NP pool)?
>
>  Aside from rolling your own, no. Lookaside lists would still have the 
>  advantage of being traced and profiled 

They seem what I need, but how do I set an upper limit in pool charge 
for a lookaside list? Can it grow indefinitely?

Emanuele

[KJK::Hyperion]

At 22.28 25/10/2004, you wrote:
> >  Aside from
> > rolling your own, no. Lookaside lists would still have the 
> > advantage of being traced and profiled 
> They seem what I need, but how do I set an
> upper limit in pool charge for 
> a lookaside list? 
define your own allocator (Allocate and Free parameters to 
ExInitializePagedLookasideList)

[Aliberti Emanuele]

KJK::Hyperion wrote:

>   At 22.28 25/10/2004, you wrote:
>
> > >   Aside
> > > from rolling your own, no. Lookaside lists would still have 
> > >  the advantage of being traced and profiled 
> >  They seem what I need, but how do I set an upper limit in pool charge 
> >  for a lookaside list? 
>
>  define your own allocator (Allocate and Free parameters to 
>  ExInitializePagedLookasideList) 
Really a nice solution! I can count how-much I de-/allocate and fail 
programmatically when the total is simply more than the set maximum pool 
charge.
thank you

[Casper Hornstrup]

Zones are pre-NT4 APIs. Microsoft recomends using lookaside lists instead.
Several ReactOS components use them (TCP/IP driver, storage stack and ntoskrnl to name a
few).

Casper

>   -----Original Message-----
>  From: ros-dev-bounces(a)reactos.com 
>  [mailto:[e-mail]] On Behalf Of Aliberti Emanuele
>  Sent: 23. oktober 2004 14:48
>  To: ros-dev(a)reactos.com
>  Subject: [ros-dev] Using zones in NTOS
>  
>  What are the advantages in using zones when allocating memory 
>  in kernel mode?
>  Are there other ways to pre-allocate an address range to be 
>  used for small memory objects management (NP pool)?
>  
>  Emanuele
>  _______________________________________________
>  Ros-dev mailing list
>  Ros-dev(a)reactos.com
>  http://reactos.com:8080/mailman/listinfo/ros-dev
>

[Aliberti Emanuele]

Casper Hornstrup wrote:

>  Zones are pre-NT4 APIs. Microsoft recomends using
> lookaside lists instead.
> Several ReactOS components use them (TCP/IP driver, storage stack and ntoskrnl to name a
> few).
>
>   
>  
Thank you for remembering me that zones are absolete. This explains why 
they are implemented in ROS with macros.

Among obsolete kernel APIs, I found ROS code often uses ExAllocatePool, 
which is marked as obsolete in the DDK. They suggest tagging memory 
wherever you allocate a block.

Emanuele