Questions[x86](server)

How much overhead does x86/x64 virtualization (I'll probably be using VirtualBox, possbly VMWare, definitely not paravirtualization) have for each of the following operations a Win64 host and Linux64 guest using Intel hardware virtualization?

• Purely CPU-bound, user mode 64-bit code

• Purely CPU-bound, user mode 32-bit code

• File I/O to the hard drive (I care mostly about throughput, not latency)

• Network I/O

• Thread synchronization primitives (mutexes, semaphores, condition variables)

• Thread context switches

• Atomic operations (using the lock prefix, things like compare-and-swap)

I'm primarily interested in the hardware assisted x64 case (both Intel and AMD) but wouldn't mind hearing about the unassisted binary translation and x86 (i.e. 32-bit host and guest) cases, too. I'm not interested in paravirtualization.

Currently I have Windows Server 2008 x64 installed on my machine. I'm about to reinstall when R2 comes out (few more days). Since I still remember all the tweaking with various device drivers, I'm thinking of installing an x86 version which has better Vista x86 driver support (that are also compatible with WinSrv2k8 AFAIK).

I have 4GB of memory which should be utilised without a problem on both platforms.

Would you suggest going to x86 or try the same driver hell all over again on x64? Would there be any significant speed issues? Memory issues?

I am/will also running several VMs of various kinds (x86 and x64). I know my hardware supports running x64 guests in x86 hosts already, so that shouldn't be a problem.

Recently I was performing an OS upgrade on one of our DB servers, moving from Server 2003 to Server 2008. The DBMS is SQL Server 2005. While reinstalling SQL on the new Windows installation, I went to another of our DB servers to verify a couple of settings.

Now, I always thought this second server was Server 2003 x64 + SQL 2005 x64 (from what I'd been told), but I now have my doubts about this. I now suspect that it is in fact only 32 bit SQL, however I'd like to verify this.

Here's some details:

The OS is definitely 64 bit.

xp_msver shows Platform as NT INTEL X86

SELECT @@VERSION shows Microsoft SQL Server 2005 - 9.00.4035.00 (Intel X86)...

However sqlservr.exe is not shown with '* 32' in taskmgr, does anyone know why this is the case, if it is in fact 32 bit as claimed? Despite this, it does seem to be running out of the x86 program files folder.

If I do the same checks on a confirmed 64 bit installation, it does give back the expected 64 bit readings, which can only prove that this server in question is only running in 32 bit.

Now, that being the case, the question arises about how much memory this '32 bit' install can use. Task manager reports about 3.5GB memory usage for sqlservr.exe (The server has 16GB physical). I suspect that AWE has not been configured at all, and therefore the server will be significantly under-utilised (remembering that the OS is 64 bit) if SQL is simply using a 32bit address space.

Is this assumption correct?

I feel the server should have SQL reinstalled as 64 bit in order to fully utilise the hardware platform, however it is currently heavily in production; this will be no easy task. I suspect we may just have to configure AWE correctly and let it be for the time being (Unless this is a bad idea?).

I apologise that this question is a little vague/lost; I'm no SQL expert, just trying to get a handle on what's going on here.

I have always wondered about this and never totally understood how 32 bit machines are addressing more than 4 GB of RAM. I mean, there are no more address lines left, correct?

I know even in our facility that we have Dell database servers with 8 GB of RAM addressable by the machine and a 32-bit version of SQL Server. Is it achieved similar to EMS memory of the 20 address line 8086, using a window of rotating memory?

What is the best free SSL VPN client that works on 64 and 32 bit windows clients?