32 bits app in 64 bits server, in the x64 Terminal Server / Citrix forum on BrianMadden.com

Hi everyone..
Con you helpme with a cuestion?
I have a server with Windows Server 2003 64 bits edition and Citrix Presentation Server for x64 bits.
The apps are for 32 bits.

My cuestion is: The app (32bits) use all features of 64 bits; or the performance is the same that if it was in a 32 bits server.

Thanks for your answer

regards

Mario Durand S.

It basically uses a WOWEXEC process to run itself in a 32bit OS. It does gain performance slightly but I would not recommend running 32bit apps on a 64 bit platfrorm as you are not getting the full potential from the 64bit operating system environment

Im running 64bit PS4 with mostly 32bit apps. Performance is on par with the 32bit server we also have but nothing special. If you only have 32bit apps, you will not notice much performance increase. The benefits of 64bit for you would then be higher memory capabilities and overall system performance. If price is comparable might as well go 64bit and future proof your setup.

ORIGINAL: jasebert

It basically uses a WOWEXEC process to run itself in a 32bit OS. It does gain performance slightly but I would not recommend running 32bit apps on a 64 bit platfrorm as you are not getting the full potential from the 64bit operating system environment

Obviously this would be the case, but in the real world - all your enterprise apps are just not suddenly going to be 64bit. Hell, we are still running 16 bit apps out there from vendors!

I had a similar question to this - essentially you'll be able to put more RAM in these things running a 64 bit OS (eg. 8 or 16GB), PS 4.x itself will probably take advantage of it, but it will take a long time before our apps all are 64 bit I suspect.

So - I'm thinking you will overall get more users/box though the apps will perform the same. Is this a correct assumption?

Also - how does PS 4.5 use dual vs. quad core procs? Which is better? Our environment is we are running all remote desktops with a lot of applications deployed to hundreds of users in a fairly sizable farm.

Thanks

Hi Joe,

In responce to your comment in relation to 64 bit enterprise applications, you have to remember all new servers (from last year) are 64 bit capable and you can install 32 bit OS on them (you are probably doing it now).

For the rest of your questions, read this :)

http://www.wtstek.com/item2/Article_64Bit_20070424.htm

There are numerous parameters that impact the performance and scalability of a Terminal Server. As a result there is no easy answer to the question. Moreover, as has been pointed out, the applications remain 32bit even when running on top of a 64bit server. OTOH the OS on which the applications are running in this scenario is 64bit, and any gains to the OS also impact the applications.

There are two main benefits in using a 64bit TS:

1. A 64bit OS can manage more memory so while each 32bit application gets the same address space (more-or-less), the number of applications you can run simultaneously, as a factor of memory, goes up.

2. The kernel address space is no longer limited to 2GB. As a result limitations on kernel resources, e.g. handles, essentially disappear. This removes a major restriction on the number of applications you can run simultaneously.

Two additional points to note:

1. 64bit servers are newer and as result generally more powerful than the 32bit servers you already have.

2. An RTO whitepaper that analyzed server performance (http://critical3.com/clients/pinPointNewsLetter/docs/RTO_Terminal_Services_Scalability_Study_PART-1_The_Effect_of_CPS_4_0.pdf) showed that installing Citrix on a Terminal Server can significantly reduce server capacity. In the context of 64bit, this whitepaper also showed that x64 improves capacity when it has enough of memory, but can actually have lower capacity than 32bit if it doesn't have enough memory.

A final point: as far as I know only Citrix and Ericom PowerTerm WebConnect currently support 64bit Terminal Servers.