JIT, NGen, and other Managed Code Generation Stuff - All Comments

re: Array Bounds Check Elimination in the CLR

Ondrej Petrzilka — Sun, 17 Mar 2013 01:59:32 GMT

I miss one piece of information, this will make bound checks on x86:

for(int i = 0; i < array.Length; i++)

array[i] = MyMethod(i);

However this won't:

for(int i = 0; i < array.Length; i++)

MyMethod(out array[i], i);

I guess problem is that "i" variable is on stack when MyMethod is called in first example, however in second example, it's not on stack (only it's copy is), so it's safe to skip bound check.

In second example, when "i" is changed when running MyMethod, it's ok, because it's incremented and checked (by loop check), before being used as array index.

Great article!

re: Improvements to NGen in .NET Framework 4

sonic7777 — Sat, 17 Nov 2012 23:34:31 GMT

Just need to run I think the above command and that makes the image for ngen 2.0 to run in 4.0.

re: Improvements to NGen in .NET Framework 4

Sonic — Sat, 17 Nov 2012 23:32:37 GMT

So do I run the command "%WINDIR%\Microsoft.NET\Framework\v4.0.xxxxx\ngen.exe install <2.0 assembly> " to make netframework 2.0 applications run in net framework 4.0? I have a chipset driver that installed (intel) and it targets the ngen 2.0 which is now disabled after update to 4.0. I want to ensure that my applications and drivers will run properly in ngen4.0.

I think you reboot afterwards but I am not sure if this above command is right. If I run this or another command do I need to change ngen2.0 to manual? It's disabled.

re: NGen: Measuring Working Set with VMMap

Jamal — Tue, 23 Oct 2012 21:23:29 GMT

I am using .NET 3.5 and my application uses 290 MB of Working Set (10 MB managed heap) when one instance of app is deployed. When two instances of the same app are deployed it takes 390 MB of heap for each instance. Will the NGEN technology help reduce the memory footprint of the apps in this case. Particularly if we have 10 different apps deployed in the same machine.

re: NGen: Getting Started with NGen in Visual Studio

Jeff O — Thu, 18 Oct 2012 14:59:31 GMT

Our app has some 30 accompanying DLLs, so of which are 3rd party supplied. Can nGen be used on this type of solution? How would one go about creating the file NI images for an application like this?

re: NGen: Getting Started with NGen in Visual Studio

crazy — Wed, 11 Apr 2012 05:43:14 GMT

hi ..

i, usunig ngen uninstall mscrolib ...

i am using vissual dtudio 2010....while issuing the above cpmmand error msg show cannot find specified path

re: NGen: Walk-through Series

arun.passioniway — Sun, 19 Feb 2012 19:18:43 GMT

Good links pracheeti. Thanks for your efforts in putting them here for us.

re: NGen: Walk-through Series

Matthias Mueller — Thu, 26 Jan 2012 22:05:15 GMT

Hello Pracheeti,

I read your great 2010th article "NGen: Measuring Working Set with VMMap".

And I have several questions on the NGEN, ASLR, and Rebasing issues you mentioned.

Maybe you can bring some more light in these topics.

1) Regarding Vista and newer, is it still necessary to do a basing of one's managed DLLs when generating NIs to achieve code sharing?

2) If basing is still necessary, do I have to calculate the base addresses based on the NI's size (which is twice as large as the IL)?

3) If basing is no longer required, will the NIs code pages still get shared among different processes using the same DLL?

Best regards

-Matthias

re: Improvements to NGen in .NET Framework 4

wraith — Fri, 02 Dec 2011 16:27:55 GMT

Hi Surupa,

We're trying to generate native images for approx 3000 (!) assemblies and faced with a problem.

After installation the files are queued up with 'ngen /queue' command and there is a reboot performed slightly later and after the machine comes up some files are not getting ngen'd... the queue seems to be empty.

Before the reboot, it is clearly visible that files were in 'StatusPending' state.

Any idea?

re: Improvements to NGen in .NET Framework 4

khan — Wed, 12 Oct 2011 00:09:40 GMT

i see. AC is looking for partner here. if surupa is married then not good for AC :(