3GB switch my findings 4

[SBaugh]

I don't know if this will be helpful to anyone, but I wanted to share this with all of you.

I was reading back through thread559-189982 and decided to investigate 3GB switch again.

I started reading up on just about all the 3GB articles I could find. I read Ed Eaton's and Wayne Tiffany's articles on the 3GB switch along with Microsoft's info. but Wayne Tiffany showed me the most of what can be done.
thread559-155411

http://kcswug.com/documents/articles/

Other articles I found:

http://www.gehrytechnologies.com/catia/catia/catia_windows_large_memory.htm

http://www.amiravis.com/3GBswitch-instruction.html

On my system I have just 3GB of RAM. But XP of course could only use 2GB still. I initially used the MS line for the 3GB switch and I have to say it ran like crap... it was slower, SW was slower it was ridiculous. So I went back to just the readable 2GB. I had not pursued it further until this morning. I am still testing, but I found an option that seems to have worked.

[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional 3GB Limited" /fastdetect /3GB /userva=2000

This one worked for me. I have other bootable lines, but this one works and the memory allocation is actually better then it was before. I don’t have an AV on my system and that does allow for less memory to be taken away from Windows and SW. Which is why I don’t want an AV, I will take my chances. I now have Outlook open along with IE, Mozilla (4 tabs), SW (complex assembly opened), Word, 2 windows Explorers, Task manager and my boot.ini file opened. I am approximately using just around a single GB of memory. I have a total of 36 processes running along with my PDMworks services running on this machine.

I have to say I am very impressed as before I would be running a higher amount of memory and running slower.

But this is just how my system is reacting to these changes. Your Mileage may vary... so if you decide to pursue the 3GB switch I recommend those articles and any others you can find online. Then try it out on your system as long as you keep your default boot, you should not have to worry about not getting back into windows.

,

Scott Baugh, CSWP

http://www.scottjbaugh.com

"If it's not broke, Don't fix it!"
faq731-376

 

[JMirisola]

Thanks for the info, Scott!

Jeff Mirisola, CSWP
CAD Administrator
SW '07 SP2.0, Dell M90, Intel 2 Duo Core, 2GB RAM, nVidia 2500M

http://designsmarter.typepad.com/jeffs_blog

 

[EEnd]

I think that running without the /3GB switch is equivalent to /3GB /userva=2048, and running with just /3GB is equivalent to /3GB /userva=3072. Using /userva=2000 is likely to leave less memory available for applications than running without the /3GB switch.

In

http://support.microsoft.com/kb/316739/

Microsoft recommends /userva=2900 or less for stability. This is probably why some experience problems when the /3GB switch is enabled; by default it sets aside too much space for applications, and not enough for the OS.

Eric

 

[SBaugh]

I have to say the 2000 is giving me great stability and the system is running better then it has in the past. Once i reached 1GB of memory my system started running slow and SW would run even slower sometimes... but now it's a lot better.

Cheers,

Scott Baugh, CSWP

http://www.scottjbaugh.com

"If it's not broke, Don't fix it!"
faq731-376

 

[gwubs]

SBAUGH - I agree with you that any time you can run a PC without antivirus, it has positive benefits. My SW machine at home is not online, never will be, and has no AV installed. What stikes me about that machine whenever I use it, is how crisp and fast it runs. We also use a laptop - Dell M90 - for mobile reverse engineering. It has never been connected to a network, doesn't run AV and is rock solid, fast, and stable. I am not suggesting that networking/being online is bad, or that AV is, it seems a shame that our high powered SW computers that are online, spend significant resources on keeping out worms and virus's....

 

[PDMAdmin]

As with CAD systems, some AV programs are more resource-intensive than others. Running Windows without an effective AV/anti-spyware program is not something I would ever recommend, since it affects not only the user's machine and network, but also every computer/network that comes into contact with that user's machine. (Many viruses are capable of spreading through an open e-mail client or simply being connected to a network, without any effort required from the user.) The wrong "baddie" on your computer could bring your network to a screeching halt, causing lots of grief and downtime for your coworkers and potentially even your customers. Is that worth the ability to run 20 programs at the same time?

Bottom line: For people like Scott, who know what they're doing, running without AV can work, as long as lots of caution and know-how are involved. For the rest of us, why take unnecessary risks?

Just my $0.02

 

[Theophilus]

Whatever it's worth, I use a compact AV solution (also inexpensive) that uses MUCH fewer of my system resources that the kludge known as Norton Internet Security (total RAM pig). I use Avast Professional and have had no problems with slow-down issues, etc. I checked what it does in the Task Manager and the RAM usage is negligible (I'm using 3GB of RAM also with the /3GB switch).

Scott, would you mind doing a check with the new SW benchmark and posting updated results with your present configuration? I'm quite interested in knowing what sort of difference you're seeing in performance with that bit of code in the boot.ini.

Also, can someone else explain what the "new" bits of code in the file really mean/do? I'd like to understand what's going on before making the change in my own system. Eric mentioned variations in the settings above, but I don't quite understand what is being done with those settings.

Thanks!



Jeff Mowry

http://www.industrialdesignhaus.com

Reason trumps all. And awe transcends reason.

 

[CorBlimeyLimey]

Basically the userva is a fine tuner for the /3GB switch.

Use of the /Userva switch
With the /Userva switch, you can customize how the memory is allocated when you use the /3GB switch. The number following /Userva= is the amount of memory in megabytes (MB) that will be allocated to each process. If you set /3gb /Userva=3030, this reserves 3,030 MB of memory to the process space, as compared to 3,072 MB when you use the /3GB switch alone. The 42 MB that is saved when you set /Userva=3030 is used to increase the kernel memory space, free system page table entries (PTEs). The PTE memory pool is increased by the difference between 3 GB (specified by the /3GB switch) and the value that is assigned to the /Userva switch.

 

[CorBlimeyLimey]

This is one of the better explanatory links

http://support.microsoft.com/kb/316739

 

[CorBlimeyLimey]

This is very interesting;

Taken from

http://www.microsoft.com/whdc/system/platform/server/PAE/PAEdrv.mspx

PAE is supported only on 32-bit versions of the Windows operating system. 64-bit versions of Windows do not support PAE. For information about device driver and system requirements for 64-bit versions of Windows, see 64-bit System Design.

Although support for PAE memory is typically associated with support for more than 4 GB of RAM, PAE can be enabled on Windows XP SP2, Windows Server 2003, and later 32-bit versions of Windows to support hardware enforced Data Execution Prevention (DEP).

I interpret that to mean that a 32 bit system can use more than the stock 4GB. Can anyone shed more light on this?

 

[Standing]

Jeff,
I use Avast at home and never thought about going to Professional. I will check it out.


Bradley
SolidWorks Premim 2007 x64 SP4.0
PDM Works, Intel(R) Pentium(R) D CPU
3.00 GHz, 5 GB RAM, Virtual memory 12577 MB, nVidia 3400

 

[Theophilus]

Thanks, CorBlimeyLimey. I've got some reading to do.



Jeff Mowry

http://www.industrialdesignhaus.com

Reason trumps all. And awe transcends reason.

 

[StefanHamminga]

PAE is nice, but i've never seen anything in NVIDIA release notes about supporting it... Taken from this link (a more descriptive link about PAE):

http://www.microsoft.com/whdc/system/platform/server/PAE/pae_os.mspx

Driver Issues
Typically, device drivers must be modified in a number of small ways. Although the actual code changes may be small, they can be difficult. This is because when not using PAE memory addressing, it is possible for a device driver to assume that physical addresses and 32-bit virtual address limits are identical. PAE memory makes this assumption untrue.

So if stability goes down the drain when enabling PAE try updating your drivers before giving up. I've personally never messed with PAE (64bit is the future in my opinion).

Stefan Hamminga
EngIT Solutions
CSWP/Mechanical designer
Searching Eng-Tips forums

 

[CorBlimeyLimey]

Thanks for the link, Stefan.

64 bit is definitely the way to go for memory issues, but unfortunately, some (most ?) of us are going to be stuck with 32 bit for quite a while.

 

[StefanHamminga]

http://support.microsoft.com/default.aspx?scid=kb;en-us;888137

I found this while doing a quick google on PAE... Seems like PAE in XP SP2 is only to be able to turn DEP on (a safety feature, which most people don't use). The amount of RAM does not differ from /3GB anymore.

Also I came across a site hinting that AGP videocards could be robbing address space in the address region that is used by the 3GB swich, so perhaps experimenting with BIOS settings (lower AGP apperture) could make larger Userva settings stable

Stefan Hamminga
EngIT Solutions
CSWP/Mechanical designer
Searching Eng-Tips forums