performance impact of vmware tools

[LucasAlbers]

We have had some discussions concerning the performance impact of installing vmware tools on a vm.

Are their any comparison's between a system running vanilla versus one running with the vmware tools installed?

Obviously I think the system will run faster with the vmware drivers installed.

[weinstein5]

It is not that the system will run fatser per se but you will get better perfomance out of your virtual hardware - if you do not install VMware tools you will rely on device drivers (netowrk, scsi, video, mouse etc) that are designed for physica hardware - with vmware tools these are replaced with drivers that are deisgned for the virtual environment and give your best performance - l

If you find this or any other answer useful please consider awarding points by marking the answer correct or helpful

[LucasAlbers]

Has anyone done any measurements of the performance difference?

We have a deployment where vmware tools are not installed, because we disagree about the level of performance improvement.

My opinion is that it has a marked performance improvement, but I cannot find any ballpark figures for the difference.

In my case this is for redhat servers.

[Rumple]

I doubt anyone has any benchmarks because we all install the tools. Compare not installing the tools to not installing the motherboard chipset drivers on a physical system. It will work, but you will have performance problems.

Also, you lose transparent page sharing I believe (but cant' remember..maybe it was just ballooning) and your scsi and network will using higher utilization then if its using optimized drivers.

[AndreTheGiant]

VMware Tools can provide:

• "paravirtualized" drivers that (usually) are faster than the emulated one

• memory balloon driver (that can optimize memory usage on ESX)

• VM heartbeat

• guest script integration (for example to guest shutdown or VCB pre-freeze)

• time synchronization

The first 2 point could usually improve overall performance.

Andre

**if you found this or any other answer useful please consider allocating points for helpful or correct answers

[Scissor]

I'm curious... what reason do your coworkers give for not wanting to install the VMware Tools?

[LucasAlbers]

His argument was:

no signifigant performance improvement.

redhat won't support non redhat drivers.

[Randall Robertson]

Tools will only help I/O performance (besides generally making things like graphics and time synchronization work better). If your VM has no significant networking or storage requirements, then you probably don't need tools. I usually don't bother.

If you want very good networking performance without tools, do make sure you are using e1000 virtual device. You can set ethernet0.virtualDev="e1000". This is not quite as good as real vmxnet (or new vmxnet3) but is a lot better than the default vlance. If you are regularly pushing 1Gbit or more actual traffic to your VMs, I would consider doing this.

Paravirtualized SCSI is fairly new, but from benchmarks I've seen it gives a fairly significant performance boost. But again, most probably you do not need it, unless you are running a very disk I/O heavy VM, such as an Oracle database server.

If you are consolidating underutilized physical machines which don't ever use 100% CPU/Network/Disk, then tools are probably a waste of time. But if you want as close as possible to native performance and CPU usage during intensive I/O, then tools are worth it.

As for Redhat not supporting our VMware Tools Drivers, I don't see why this would practically be a problem- if you have some issue/crash that you think may be related to our tools, you can always uninstall them and go back to where you were before. If you have an unrelated issue, and you are worried Redhat would refuse to help you because of tools, you can do the same. So what is the harm in trying them?

^^ If you found this post helpful, please consider buying me a beer some time :smileyhappy:

[LucasAlbers]

an article on the performance comparision between the intel and vmxnet card.

Description

The networking performance of a virtual machine is greatly influenced by the choice of virtual network devices in the virtual machine and the physical devices configured on the host machine. ESX Server 3.5 supports multiple virtual network devices (vlance, e1000, vmxnet), each with its own usability advantages and performance benefits. It is clear that vlance is not the best choice for high-performance workloads. However, many users are still uncertain about the performance differences between e1000 and vmxnet virtual network devices.

[Josh26]

The difficulty is that for anyone in an enterprise environment running a cluster and hoping to use HA etc, the tools are necessary, whether you want the performance or not.

Unless you plan on never growing, this will be something you'll have to face at some point.