i need to run a few visual studios on windows XP and it seems to take up a lot of memory. i am also running resharper which is a memory hog.
i am running 32 bit XP. How much memory can i put into my machine until i get to the point where the OS hits its limit.
Also, any other ways of running multiple visual studio without such slow performance.
32-bit Operating Systems are limited to 4 GB of RAM, which may or may not be enough for you. Also, I think Windows shows 3 GB of RAM if you install 4 GB.
I suggest you switch to 64-bit and upgrade to 8 GB if you can.
UPDATE: See Jeff's blog post on the subject: Dude, Where's My 4 Gigabytes of RAM?
The maximum amount of memory that can be seen by 32bit WinXP is somewhere between 3 and 4 gigabytes depending on your chipset.
I have also run into issues running multiple instances of VS when I had resharper installed. The only thing you can do is run 64bit XP with more memory, or not use resharper (which is a bummer).
32-bit Windows kernel divides the 4GB virtual addressing space in 2GB/2GB partitions. If you feed the /3GB switch to NTLDR it will offer 1GB kernel space / 3GB user mode space. Note that this NOT implies that you can't write software to take advantage of machines with 32-bit CPUs and address more than 4GB at once.
A workaround is the hardware-supported feature to access the remaining memory in banks or "windows" since the CPU still sees a maximum of 4GB addressable space at once. Some database and GIS software offer this possibility. This is called Physical Address Extensions and allows to use (not addressing at once) up to 64GB with 36-bit addresses. WinXP offers AWE, an API built on top of PAE.
That's the theory. For using Visual Studio you can get the full 4GB for your system or upgrade to a 64-bit OS with more RAM. This only if VS offers a 64-bit version.
"Also, any other ways of running multiple visual studio without such slow performance."
+1 trick: you should use a RAM disk (download) to accelerate I/O.
If you're using - and hopefully do - source-managament system (ie. Subversion), you must just checkout your projects there. VS.NET makes tons of I/O calls, and RAM disks are much faster than real disks.
CAUTION! If you turn off your computer, RAM Disk disappers.
Related
My original question is that, is this technically rational to check the required heap-size of my Java program on Windows 7, via VisualVM, and come to this conclusion that the program will require the same amount of heap on Linux(RedHat) as well?
I don't know how the system(OS or even CPU and RAM), affect memory management of JVM.
well, the windows is my development system with 4GB of RAM and a Core 2 Due CPU, however the
Linux is the production system with 32GB of RAM and multiple powerfull processors,
Actually, my concern is that the program on Linux might need more memory. less is ok.
I hope someone with a bit of knowledge can clear this up. There's many discussions about the reasons to run a 64-bit OS (e.g. Windows 7 x64), but many people seem to think that their old x86 apps will be able to take advantage of any RAM greater than 3.5GB.
As I understand it, though, x86 apps cannot address memory that high... unless they've been specifically programmed to (which very few will have).
Can someone knowledgeable clear this up for me, once and for all? Can 32-bit apps take advantage of a system running 8GB of RAM?
E.g. If a user decided (for whatever reason) to run several x86 apps at once, filling the RAM as much as possible, would the extra addressable memory available in Windows 7 x64 be used?
Thanks!
On a 64 bit system, 32 bit applications are able to use the full 4GB virtual address space, minus about 64K. A default 32 bit windows system will only allow a 32 bit process to use 2 GB of virtual address space. By specially configuring the OS it's possible to push that limit up to 3 GB, but it's still not as good as what you would get on a 64 bit version of windows.
If you have 8GB of ram, that 8 GB can be divided up between multiple 32 bit processes, and the entire 8 GB will be utilized if necessary. However, no single 32 bit process will be allocated more than 4 GB of memory.
Although i don't have sources to cite, but from my knowledge: 32bit app will not be able to address more than 4GB of memory itself, unless it uses some tricks(that is very unlikely), but if you have some 32bit apps running at the same time, they can all have 4GB each, and thus two 32bit apps should be able to use all 8GB of memory. Though I'm not 100% sure.
Yes. x86 apps cannot use more than 2GB of memory at once without special tricks, but they can use any memory available.
Adding to the other (correct) answers:
Instead of the term "application" the word "process" should be used. Applications often consist of multiple processes whereas the limits discussed here apply to single processes.
Thus applications benefit from x64 that either are linked with the LARGEADDRESSAWARE flag (they can use 4 GB instead of 2 GB) or that share the load between multiple processes.
32-bit processes can work with more than 4 GB RAM even on 32-bit systems by using AWE. But a 32-bit process can only ever use 2 GB at once (4 GB with LARGEADDRESSAWARE on 64 bit respectively). AWE is primarily used by databases where it is essential for performance that the entire database fit into RAM. It works by providing a 2 GB window into a larger chunk of memory.
Here are some articles for further reading:
Windows x64 – All the Same Yet Very Different, Part 1: Virtual Memory
Windows x64 – All the Same Yet Very Different, Part 2: Kernel Memory, /3GB, PTEs, (Non-) Paged Pool
x64? My Terminal Servers Run Just Fine With 32 Bits and 8/12/16 GB RAM!
E.g. If a user decided (for whatever
reason) to run several x86 apps at
once, filling the RAM as much as
possible, would the extra addressable
memory available in Windows 7 x64 be
used?
The answer is yes. That's one of the benefits a virtual address space gives us--the ability for each process to appear (to the process) as though it's executing in a linear address space that starts at 0 and goes up from there.
As far as each of the 32-bit applications is concerned, it has its own address space from 0 to 2 gigabytes (without special tricks). The operating system handles the virtual-to-physical address translation.
Imagine the same hardware running Windows XP 32bit, or Windows XP 64bit..
(being that it's a 64bit processor currently running XP 32bit)
2gigs of ram...
Will the performance of Visual Studio benefit from going to the 64bit OS?
The hardware and ram is currently out of my control... If I could throw more hardware or ram at it I would.
For 2 GB of RAM, most likely not. The biggest advantage of 64-bit is the additional address space. With 2GB of physical RAM, 32-bit OS's can map all of physical memory.
Above 3GB 64-bit OS does give some benefit, since some of your physical memory may be unusable on 32-bit OS's due to devices mapping physical addresses for their own use.
And obviously if you want to use above 4 GB of memory you should absolutely go for a 64-bit OS.
Yes, if you have sufficient physical memory, you will gain some benefits from running Visual Studio in 64-bit Windows as described in Visual Studio: Why is there no 64 bit version? (yet):
Doesn’t being a 64 bit application save you all kinds of page faults and
so forth?
A 64 bit address space for the process
isn’t going to help you with page
faults except in maybe indirect ways,
and it will definitely hurt you in
direct ways because your data is
bigger. In contrast a 64 bit
operating system could help you a lot!
If you’re running as a 32 bit app on a
64 bit OS then you get all of the 4G
address space and all of that could be
backed by physical memory (if you have
the RAM) even without you using 64 bit
pointers yourself. You’ll see
potentially huge improvements related
to the size of the disk cache (not in
your address space) and the fact that
your working set won’t need to be
eroded in favor of other processes as
much. Transient components and data
(like C++ compilers and their big .pch
files) stay cached in physical
memory, but not in your address space.
32 bit processes accrue all these benefits just as surely as 64 bit
ones. (my emphasis added)
not unless you add more RAM.
In fact 64 bits might even slow you down because 64-bits Windows sometimes have to load both 32-bits and 64-bits versions of a same DLL in RAM.
Add more RAM is the way to go because if you are using Windows 7 or Vista they aggressively caches disk files in RAM.
I have ASP.NET 2.0 applications running on 32 bit Windows 2K3 Standard edition with 4GB of RAM. I want to upgrade the server to Enterprise edition and add more memory to a total of 6GB. I assume that I will need to enable PAE extensions to do this.
How much of this extra 2GB will be usable to the W3WP worker processes? The root issue is that 2 of the WPs are exceeding 900MB every so often and causing OutOfMemory Exceptions.
The alternative is that I get a new server and move half the applications to it, which is a more expensive and time consuming option.
Thanks
In order to use the extra 2GB /PAE must be enabled in the boot.ini. Each WP will then still be limited to 2GB physical memory.
http://support.microsoft.com/kb/283037
http://msexchangeteam.com/archive/2004/08/20/217772.aspx
You will not need the PAE extensions. As long as you don't have a WP that needs more than 2GB of its own.
Obviously, that's 64-bit windows.
Also, what's the maximum amount of memory a single 64-bit process can use?
I was kind of counting on using it all...
(Yes, I know what I'm doing, please don't tell me that if I need that much RAM i must be doing something wrong)
Also, is this the same for a .Net 2.0 process? Or is there a lower limit for .Net?
What version of windows? it differs from XP to vista and from home to business versions of vista, and I would guess again for server.
see here for more info on maximum ram for diffrent windows versions
for Windows Server 2008 Datacenter MS quote 2 TB of physical memory.
Link
From http://technet.microsoft.com/en-us/library/cc758523.aspx
- Windows Server 2003, 64 bit Datacenter Edition supports physical memory up to 512GB
A single process should be able to use most of it, some will be used by the OS.
The answer from Re0sless is better then mine. The limit is now 2TB, in Datacenter SP2, and 2008.
We run Windows boxes with 16 gigs of memory, but that is because we are running multiple VM Ware instances, I presume you mean in a single instance. On Vista it depends upon the edition. It breaks out like this:
Vista Basic: 8 GB
Vista Home Premium: 16 GB
Vista Business/Enterprise/Ultimate: 128+ GB
Something we found out recently: with MySQL running on Win32, you can only use up to 2GB per process. On Win64, the memory is not managed as well and a single MySQL instance will run your memory into the ground. Ours used up all 16GB we have. So regarding how much memory 1 64-bit process can use: the answer is however much the OS allows.
According to wikipedia you can have 128 GB of physical RAM in a 64-bit Windows XP computer.
This is a Windows Server machine.
As for which edition (Datacenter, Enterprise, etc)... Whatever it takes to give my little .Net Process as much memory as it can.
Switch to Linux. You will not have any of these issues and you will get better performance.