VMWARE 5.5 ...
Experimental support for 2-way Virtual SMP
Assign up to two virtual processors to a virtual machine. Users can create more realistic and powerful development and testing environments when working with multi-threaded, resource-intensive software. This capability is available for all supported configurations of 32-bit and 64-bit host and guest operating systems running on multi-processor host machines, including dual-core and hyper-threaded, uni-processor machines.
I read that and immediately started the download.
I have an 2 cpu Dell machine in the basement I use a lot – my main desktop type machine (it is a 10lb notebook) has a hyperthreaded P4 in it so – I was very interested in SMP support in vmware. Normally, vmware uses 100% of one cpu when it is doing something really intense. Now with this setup, I can get 100% of both cpu’s going. Huge difference in performance. The main reason this is “good” – Oracle algorithms change radically when cpu_count goes from 1 to more than 1 (but don’t set it to more than 1 on a single cpu machine! It won’t be “a good thing”). In order to do tests of how something might scale (based on latch usage and such), I always had to get to my larger machines. Now I can do some of that on the road easier (and demonstrate the differences too – I could only report “what happened on another machine” instead of showing it).
Not only that – but the 2 cpu VM’s run faster on my machines so far than the 1 cpu VM’s – by a measurable difference (we are not talking fractions of a second here, it is so far significant). In order to test, I installed the same OS (red hat AS 4.0) twice using the same options – only one time the SMP version built itself and the other time a single cpu version. Then I installed 10gr2 twice on both VM’s. Other than one having 2 cpus and one having only 1 cpu – they were configured identically. The database runs measurably faster doing cpu intensive operations on the 2 way VM.
So, I’ll have to disagree with Howard as to this being a “non event”. The one thing I needed in vmware was this feature (SMP support). It was available only in their high end server product before, now that it is in the workstation offering – I can use vmware for even more stuff.
Only downside, now I have to rebuild some VM’s… But actually, that is a good thing – cleans them out. This time I’m going to keep my Oracle installs separate on linux (10gr2 in its own vm, 10gr1 in its own and so on). It was handy having them all in one, but there are advantages for having them separate.