What is the default depth of lookaside list ?
Some value invented by the OS. You’re not supposed to know it. Just specify
0.
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
xxxxx@storagecraft.com
http://www.storagecraft.com
----- Original Message -----
From: “Abhijit”
Newsgroups: ntdev
To: “Windows System Software Devs Interest List”
Sent: Wednesday, March 31, 2004 4:38 PM
Subject: [ntdev] Lookaside list
> What is the default depth of lookaside list ?
>
>
>
> —
> Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256
>
> You are currently subscribed to ntdev as: xxxxx@storagecraft.com
> To unsubscribe send a blank email to xxxxx@lists.osr.com
Ya, specifying 0 is fine. I just wanted to know the depth of list which OS
creates (when we pass 0 of course)
Thanks
Abhijit
“Maxim S. Shatskih” wrote in message
news:xxxxx@ntdev…
> Some value invented by the OS. You’re not supposed to know it. Just
specify
> 0.
>
> Maxim Shatskih, Windows DDK MVP
> StorageCraft Corporation
> xxxxx@storagecraft.com
> http://www.storagecraft.com
>
>
> ----- Original Message -----
> From: “Abhijit”
> Newsgroups: ntdev
> To: “Windows System Software Devs Interest List”
> Sent: Wednesday, March 31, 2004 4:38 PM
> Subject: [ntdev] Lookaside list
>
>
> > What is the default depth of lookaside list ?
> >
> >
> >
> > —
> > Questions? First check the Kernel Driver FAQ at
> http://www.osronline.com/article.cfm?id=256
> >
> > You are currently subscribed to ntdev as: xxxxx@storagecraft.com
> > To unsubscribe send a blank email to xxxxx@lists.osr.com
>
>
Typically it doesn’t create any depth, the first calls to it will initiate
a call to the alloc routine.
Last time I investigated this several years ago, I found that there’s a
system thread that goes around does housekeeping on all the
LookasideLists. It heuristically determines how deep a list of elements to
leave on the list based upon your usage of the list … hence Max’s comments.
If you actually want control of how the list behaves, then write your own
versions of ExInitialize(N)PagedLookasideList and
ExDelete(N)PagedLookasideList. Depending on how you want the list to
behave, you would either have to have a scavenger thread similar to how
Windows does it or add functionality into your own user defined Alloc and
Free functions.
I don’t see much point in doing that, you’ll waste too much time
re-inventing not as good a wheel as already exists when you should be
coding functionality.
Anyway, I note that the latest DDKs say that the Depth value is reserved
and must be passed as zero.
Mark.
At 09:56 AM 4/1/2004, Abhijit wrote:
Ya, specifying 0 is fine. I just wanted to know the depth of list which OS
creates (when we pass 0 of course)Thanks
Abhijit“Maxim S. Shatskih” wrote in message
>news:xxxxx@ntdev…
> > Some value invented by the OS. You’re not supposed to know it. Just
>specify
> > 0.
> >
> > Maxim Shatskih, Windows DDK MVP
> > StorageCraft Corporation
> > xxxxx@storagecraft.com
> > http://www.storagecraft.com
> >
> >
> > ----- Original Message -----
> > From: “Abhijit”
> > Newsgroups: ntdev
> > To: “Windows System Software Devs Interest List”
> > Sent: Wednesday, March 31, 2004 4:38 PM
> > Subject: [ntdev] Lookaside list
> >
> >
> > > What is the default depth of lookaside list ?
> > >
> > >
> > >
> > > —
> > > Questions? First check the Kernel Driver FAQ at
> > http://www.osronline.com/article.cfm?id=256
> > >
> > > You are currently subscribed to ntdev as: xxxxx@storagecraft.com
> > > To unsubscribe send a blank email to xxxxx@lists.osr.com
> >
> >
>
>
>
>—
>Questions? First check the Kernel Driver FAQ at
>http://www.osronline.com/article.cfm?id=256
>
>You are currently subscribed to ntdev as: xxxxx@muttsnuts.com
>To unsubscribe send a blank email to xxxxx@lists.osr.com
I remember some article on OSR site talks about Lookaside lists on NT 4 has
some pointer to this information.Please search for it too.
Regards
Subodh
Software Architect
Knowledge Architects Web India.
+91-9892335325
----- Original Message -----
From: “Mark S. Edwards”
To: “Windows System Software Devs Interest List”
Sent: Thursday, April 01, 2004 3:13 PM
Subject: Re:[ntdev] Lookaside list
> Typically it doesn’t create any depth, the first calls to it will initiate
> a call to the alloc routine.
>
> Last time I investigated this several years ago, I found that there’s a
> system thread that goes around does housekeeping on all the
> LookasideLists. It heuristically determines how deep a list of elements
to
> leave on the list based upon your usage of the list … hence Max’s
comments.
>
> If you actually want control of how the list behaves, then write your own
> versions of ExInitialize(N)PagedLookasideList and
> ExDelete(N)PagedLookasideList. Depending on how you want the list to
> behave, you would either have to have a scavenger thread similar to how
> Windows does it or add functionality into your own user defined Alloc and
> Free functions.
>
> I don’t see much point in doing that, you’ll waste too much time
> re-inventing not as good a wheel as already exists when you should be
> coding functionality.
>
> Anyway, I note that the latest DDKs say that the Depth value is reserved
> and must be passed as zero.
>
> Mark.
>
>
>
> At 09:56 AM 4/1/2004, Abhijit wrote:
> >Ya, specifying 0 is fine. I just wanted to know the depth of list which
OS
> >creates (when we pass 0 of course)
> >
> >Thanks
> >Abhijit
> >
> >
> >
> >“Maxim S. Shatskih” wrote in message
> >news:xxxxx@ntdev…
> > > Some value invented by the OS. You’re not supposed to know it.
Just
> >specify
> > > 0.
> > >
> > > Maxim Shatskih, Windows DDK MVP
> > > StorageCraft Corporation
> > > xxxxx@storagecraft.com
> > > http://www.storagecraft.com
> > >
> > >
> > > ----- Original Message -----
> > > From: “Abhijit”
> > > Newsgroups: ntdev
> > > To: “Windows System Software Devs Interest List”
> > > Sent: Wednesday, March 31, 2004 4:38 PM
> > > Subject: [ntdev] Lookaside list
> > >
> > >
> > > > What is the default depth of lookaside list ?
> > > >
> > > >
> > > >
> > > > —
> > > > Questions? First check the Kernel Driver FAQ at
> > > http://www.osronline.com/article.cfm?id=256
> > > >
> > > > You are currently subscribed to ntdev as: xxxxx@storagecraft.com
> > > > To unsubscribe send a blank email to xxxxx@lists.osr.com
> > >
> > >
> >
> >
> >
> >—
> >Questions? First check the Kernel Driver FAQ at
> >http://www.osronline.com/article.cfm?id=256
> >
> >You are currently subscribed to ntdev as: xxxxx@muttsnuts.com
> >To unsubscribe send a blank email to xxxxx@lists.osr.com
>
>
> —
> Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256
>
> You are currently subscribed to ntdev as: xxxxx@softhome.net
> To unsubscribe send a blank email to xxxxx@lists.osr.com
> Last time I investigated this several years ago, I found that there’s a
system thread that goes around does housekeeping on all the
LookasideLists.
Surely. That’s why forgetting ExDelete(N)PagedLookasideList causes BSOD in this
thread - in ExpScanGeneralLookasideList or such.
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
xxxxx@storagecraft.com
http://www.storagecraft.com