Comments on: KVM vs. VMware: A Case Study

By: Dan

Dan — Thu, 18 Mar 2010 15:43:53 +0000

Sure some vmware solutions are free. But as soon as you ACTUYALLY use them in production, you will realize that without vmotion, you’re gonna feel some pain.

Example: in order to add a 2nd virtual ethernet to vmware, you need to run vmware-setup.pl. Guess what, you have to shut down vmware for that ! yay !

Maturity… I have seen so many weird bugs and esoteric workarounds on vmware server 2, that I don’t put much hope is vmware’s free offerings anymore.

Bottom line is, although great, vmware free offerings are designed to lure you into pricey options. If you don’t intend to eventually buy into it, look into some other product.

By: Mr Sant

Mr Sant — Fri, 05 Mar 2010 18:17:24 +0000

Sorry help in address this point:

In case of maintenance (update of VMware release) for VMware I need to update virtual HW and so a downtime planned, maybe short. I can choose to avoid to do that

With KVM? Is an update with no impact on service continuity? If yes, how?

By: Hang

Hang — Mon, 23 Nov 2009 18:54:23 +0000

I was running VMWare ESXi because it is “free”, but I was unable to get reasonable performance. On my dual core/3G machine (desktop model) with 4 VMs running (each VM has 1 CPU, 512M mem, 10G disk), a memcached-like application (no disk IO) gave me 50ms/write. I cut to 2 VMs then I got 25ms/write, which seems 2 VMs is what VMWare can support on this box.

Then (couple of days ago) I heard of proxmox, installed, created same 4 VMs, running with same application, the number was … 8ms/write.

I could not believe the number so I searched online, and this post jumped out – if you are saying VMWare/XenServer are doing much more better would you please post your numbers?

BTW, I’m using Fedora as guest, and I don’t need any fancy features other than migration.

By: Joe

Joe — Mon, 16 Nov 2009 15:55:30 +0000

Steve Chambers, please stop. You make yourself look foolish.

By: Dean Rantala

Dean Rantala — Tue, 13 Oct 2009 13:39:12 +0000

Steve Chambers: get over it man. Are you some anti-open source spokesman?

Running both KVM and ESXi in tests at our data center I have determined (in a production environment serving http://www.nationalguard.com 24/7) KVM *is* faster. I achive less load average (under.8 on the app server) with kvm as compared to over 1.4 with esxi – this is on the guest side. So my conclusion is KVM surely runs the guest faster.

Perhaps ESXi *IS* faster is other situations.

Also note these two tests were of mirror images running Debian Lenny, Apache 2, and PHP.

As a former programmer, the low-down-n-dirty documentation for interfacing with KVM is less obscured than esxi’s.

Factor in that there are no Linux clients for esxi. The whole .Net thing is cheesy marketing partnership with Microsoft most likely.

Why do I run Open Source? Well hell, why do you run Windows? I run Linux because it was the closest thing to a [then-dying] Solaris I grew up on until several years back. And that was *NOT* free. We all use (at lease the non-zealous ones) what we use because it is what we are familiar with.

On pricing… Vsphere for 6 CPU’s: over $13,000. Give me a break. The only reason THEY are charging that much is because there are millions of Microsoft patriots who’s opinion is so clouded by *cough* religious zeal *cough* that they absolutely justify the cost.

Most people buying VMWare also work in a Corporate environment where they are spending someone else’s money. $13,000 is a raise for a good employee (or bonus for a couple) who is/are willing to learn a new technology IMO.

By: Michael

Michael — Fri, 29 May 2009 14:08:10 +0000

To add, there is a really awesome virtualization project happening that is centered around KVM and OpenVZ called Proxmox VE (Virtual Environment). It’s a turn key solution that in my opinion rivals the best features in ESX and Citrix Xen such as Vmotion and live migrations. The software is built on a highly customised Debian OS and clustering software, which is one of the most crucial features as you can live migrate virtual machines from one cluster node to another. Did I mention it is all based on a really simple GUI interface that is accessible via web browser (even has Java based VNC consoles you can open to any server in the cluster from your desktop!) I have been evaluating this software for my IT department and it looks like this is going to replace VMware and save us thousands of dollars. Check it out here:
http://pve.proxmox.com/wiki/Main_Page
There are too many features to list here, and pass the word along… it seems no one is familiar with this software, it’s amazing!

By: Christopher Tozzi

Christopher Tozzi — Mon, 25 May 2009 15:19:59 +0000

Les: the guests were both Linux and Windows server 2003. I didn’t benchmark Windows on KVM vs. Windows on VMware, but its performance was fine on both.

By: Les Stott

Les Stott — Mon, 25 May 2009 13:08:17 +0000

I didn’t see any mention of the guest operating systems that you used. I was curious whether you used windows guests or not and whether they performed better under KVM or vmware.

By: Paul Milligan

Paul Milligan — Wed, 06 May 2009 09:36:55 +0000

Some of the comments relating to *free* and *cost* simply don't make sense in a commercial environment. In most environments an IT person has a burdened cost of $60-$100 per hour. So if you spend more than a day trying to configure KVM then Vmware's $995 management suite is pretty good value for money. Almost all the paid for low end virtualization products represent reasonable investments as an alternate to relying on an administrator to hack config files. A vendor worth considering for smaller enterprises is Virtual Iron They offer a low cost solution that is more complete than Vmware's base offering.

By: aikiwolfie

aikiwolfie — Sun, 03 May 2009 14:10:03 +0000

Only some components are free. The strategy is to draw customers in with the promise of “free”. Get them hook and then hammer on the charges.

http://store.vmware.com/store/vmware/ContentTheme/pbPage.buyesxi/ThemeID.1120800&src=PaidSearch_EMEA-ALL_EMEA-ALL_VI_VI_WWW_BuyESXi