Rig to run VMs

My QA guys runs several VM at same time on the ESX box (server class). some Xeon processors, 6-8 GB RAM. Is this machine sufficient to run many VMs? Well the answer is how much exactly is MANY and what OS you intend to run on VMs. 3-4 no problem but with each next VM there is contention for the resources. On 4 GB boxes I have seen slow down even with 4 VMs. Now I have another machine with a C2D with 8 GB of RAM and a QUAD with 3 GB of RAM. I can run 2-3 VMs(in workstation) in my C2D machine with ease but Quad slows the host a lot.

Many cores are good, but RAM is a lot desired. ESX or Workstation locks the amount of memory allocated by you to the VM in the launch itself, so that it will be available when required. I do not know how well it scale on a hyper threading model as I have not used one, But I will doubt that, google it and you should know, here is one such link for you Use Hyperthreading in ESX or not?. The reason is all HT provides is context(read registers), but L1 L2, execution units and many other remain same.

Additionally if all the cores are running on full and there will be no benefit on HT (as in gaming), checkhttp://communities.vmware.com/docs/DOC-5101. Same thing goes for your network, more VMs and speed will become bottleneck, and remember its the component with least speed which decide the speed of your system.

Long story short: Check how much extra u r paying for HT, if its too much, no point getting it. RAM 8 GB or plus. For nominal work like download RIG or browsing, you do not need high end VMs but they *WILL* share network bandwidth, so you still has to increase it for better results. Additionally your HDD speed will effect the performance ion case of concurrent disk IOs, you are better if you have VMs on separate HDD (2*2).

Now I am no h/w expert so you H/W experts suggestions to buy good parts (like DA),

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@thunder.dragon

>>try to get Windows 7 instead of Windows XP as XP doesnot have support for Intel VTx or AMD-V but Windows 7 has.

Intel Vt is at Hardware level and need to be enabled from BIOS, right? And we know we can run VMs on XP, so what was ur point which I missed.
 
phreak0ut said:
Thanks for the reply thunder.dragon. How much will an i7 and a good motherboard cost? I'll go for it, only if both of them fall in my budget.
@OT

Try searching 2nd hand i7's that will save some good bucks if you are low in budget mate. For Mobo Opt any 10-12k new one.. For mobo you have many choice... Sabertooth, UD3R, Pro-E etc etc. Also get 12GB kit of Corsair XMS3 ASAP as prices are low... if possible try buying 4GB x 3 = 12GB kits instead of 2GB x 3 = 6GB kits as this will give you headroom for future RAM upgrades.

Though 6GB kits are cheap now a days, 4.1K for 6GB Corsair XMS3 1600 CL9 now from TheItBazaar.com - cheapest out there, so you can get 6 x 2GB = 12GB

As you already have 8600GT so it will help you alot saving cost. Because X58 chipsets do not have onboard Gfx. But you have to forget HDMI then, as no port is there in 8600GT, still its matter of time.

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adi_vastava said:
@thunder.dragon

>>try to get Windows 7 instead of Windows XP as XP doesnot have support for Intel VTx or AMD-V but Windows 7 has.

Intel Vt is at Hardware level and need to be enabled from BIOS, right? And we know we can run VMs on XP, so what was ur point which I missed.

Yes mate you are right that Intel VT-x should be activated in BIOS first but VT-x is a hypervisor and it helps distributing the resources efficiently from hardware level (VT-x is form of Hardware Vistualization). THough you activate in BIOS still as Windows XP don't support this feature as this is far new so in your VMWare, VBox this won't show VT-x activated. That means you can efficiently distribute your resources from the hardware level but obviously you can do the same from software level (Software Vistualization). many tools like VMware, Virtuabox, Ms Virtual PC does. So lack of support in XP won't let you utilize the awsome feature but Windows server 2008R2, Windows 7 will provide you.

To explain in better and easy way.. all the system calls, sharing of resources will be directed by the Intel VT-x / AMD-V not from the host OS's kernel (this saves bandwidth and the little lag IMO). Hope I am wrong and if I am wrong please correct me but this is what I know from my Exp.
Also to add, the link of Hyperthreading in ESX is old topic mate, get updated please, now all days all the Xeons are comming with the Hyperthreading 4cores 8threads so the organisations are even buying 6cores xeon that gives them 12 logical cores. This helps them to save cost and better scale their servers. Now a days check the HP Blade servers which comes with 2 proccy sockets and companies opting for 2 x 6 cores i.e. 24Logical cores for the each blade servers.

Scaling is awsome in these configs.

@ OT

I don't think you will be using the ESX instead I think you will be on VMware Workstation.

Also +1 to adi_vastava in case of RAMs the more you buy the more you can scale your VM's

At end it all depends what you want to RUN in VMs. If it's case like me Running demo of DEV-QA-PRD SAP instances.. get as better as u can.
 
^^

>>VT-x is a hypervisor and it helps distributing the resources efficiently from hardware level

Intel® Virtualization Technology: Hardware Support for Efficient Processor Virtualization, I checked this and it says same thing as you said about system call. So in its basic essence it allows Guest OS to run at ring 0. Though the noun Hypervisor is not applicable I think, in hypervisor case we allow guest OS to run at ring 1, where hypervisor runs at ring 0.

>>Also to add, the link of Hyperthreading in ESX is old topic mate, get updated please,

err, it does not matter how old the link is, HT is not changed drastically in last many years, this explains its clearly VMware Communities: Hyper-Threading on ESX Server and it is still same. it varies on the use of guest VM, for processor centric application running in guest, the notice will not be significant. In the end its all abt performance one is getting for the price and that is what I suggested to OP. if it is cheap get it else leave it.

Thanks for pointing to VT-x, will be a good read for some time. I'll update here in case I find something different than what we both think :).
 
@thunder.dragon & @adi_vastava .. damn you guys have awesome knowledge of virtualization.. write a blog on this.. it will help others.. besides, how about using KVM? It is also a good hypervisor.. I've read a lot about it..
 
One recommendation from the vmmon group is to leave the standard options selected by VMware (ESX/Workstation etc) whether it enables stuff like VTx/AMDv or not, because in some CPUs/OS guest/host combinations the hardware virtualisation can be slower than software MMU.
 
I'll be getting the quotes today from various shops around SP. Will post them here. I might buy them next week. If you guys know the shopkeepers well, can you please point me to the right ones and if I can get a good price? I've bought many peripherals and 2 PCs from Bangalore, but his disgusting attitude when he refused to replace a Transcend thumb drive under warranty even after the Bangalore distributor agreed to replace I don't want to go back there.

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Just back from SP Road and here is the best quote among the lot from Parvat Computers

Processor AMD Phenom II X6 1090T BE 9000
Motherboard Gigabyte GA-890GPA-UD3H 8000
RAM Corsair 2x4GB RAM XMS3 1600MHz 4100
Monitor Dell ST2220M 7600
Cabinet NZXT Gamma 2600
PSU/SMPS Corsair VX 450 3300

Total 35985 net

He has put it as 36300 net. I don't know how he came to that conclusion :p Will be leaving out the speakers for now. Will probably invest in a 5.1 sometime later. Saw a Sony 5.1(don't know the model) available for 4600 which I think is a good deal!
 
Hey guys! Back after a long time. I'll be buying my rig next week and am disappointed with our dumb CM who increased tax from 4% to 5% Also, the Dell monitor which I was looking out for (ST2210L) is also discontinued. Need suggestions on few more things. What is the difference between the mobos Asus M4A88T-M and gigabyte GA-890GPA-UD3H? If I can land with an ASUS which costs 3k less for more or less the same features, I can go for it. It's actually not about the cost, but what I'm getting out of the extra 3k on the Gigabyte. Can you guys also suggest a good 22" monitor now? HDMI preferred. Dell has cut back heavily on features for the cost per size. Now, only the 23" and 24" are coming with decent features. Thanks in advance! :)

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Just checked out the ASUS forum and found that M4A88T-M has issues. Any good ASUS mobos in the same price range or less the Gigabyte?
 
It's been nearly a month since I bought the new rig. It was really tough to get the Gamma case. Everyone was asking if it was from Coolermaster. Hehehe.... Unfortunately, the Dell monitor which I was eyeing for a long time has been discontinued. Only the 24" one has HDMI output. I'm sticking with my decade old Samtron 15" CRT :( Total cost : Rs. 30700.
 
Oh, then get the Benq G2222 HDAL for around 8~8.5k. Its a true successor of g2220 HD, with LED backlight. About the chassis, Elite 430 from CM is almost as good, but still I prefer GAMMA if its available.
 
A long pending update. Bought the rig around 2 months back and it's kickin' a$$! :D Running VMs on this machine is a dream! The base OS is a Win 7 Ultimate x64. One downside to this rig is, the horrible heatsink. Due to the small size, it needs to spin faster to cool. Sounds like a fighter jet ready to take off when it is blasting away as I run some heavy loads on the VMs. Didn't buy the monitor since Dell has decided to stop the production and the dealers are making a killing by quoting their own sweet price if we really want the same model. Will wait for few more months on the monitor since I realized that I badly need more storage now :D Thanks again for your inputs guys! :)
 
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