FreeBSD under Vmware

FreeBSD under Vmware

From: http://ivoras.sharanet.org/freebsd/vmware.html

The following tips work both under VMware ESX (2 & 3) and VMware Server 1.0 and 2.0. See also information about VMware Server 2 and FreeBSD.

1. General tips

Don't use a virtual machine for network-heavy workloads. VMware and other full-hardware virtualization alization environments (MS Virtual PC, qemu, etc .) introduce a heavy penalty on I/O, especially network I/O. fail CT to be able to get only around und 30%-40% out of a gigabit interface (which still amounts ~~ 40 MB/s ). for example, don't use virtual machines for network routers and similar tasks. also, don't use them for tasks which require exact timing (e.g. multimedia Processing, industrial machine control, etc .). these points are actually valid for any combination of virtualization software and Guest OS.

2. Don't use Lnc

This tip is no longer current, as lnc doesn't exist in FreeBSD 7. It's still valid for FreeBSD 6.3 and earlier versions.

While it's the default,LncDriver is the worst Network Driver for your virtual machine. it's giant-locked (meaning it doesn't allow for much parall1_m in the OS), and it's actually deprecated and will be dropped in FreeBSD 7. the replacementLncIsLeAnd it's present at least in FreeBSD 6.2 and newer, but it's not supported in the default generic kernel. Thus, you'll have to configure and compile a custom kernelDevice lncReplacedDevice le. (Just loadingIf_leKernel module won't work becauseLncDriver present in the kernel at boot time will detect and use the hardware first .)

There's an uninitialized ented configuration option for the virtual machines that enables VMware to emulate intel e1000 hardware instead of the amd Lance. To use it, edit the. vmx file and putEthernet0.virtualdev = "e1000"In the appropriate place (anywhere ). the simulated device also Has TSO support (which is usable in FreeBSD 7, though I don't know what performance can be achieved with the simulated hardware ). deviceEmIs faster and not giant-locked so it shoshould give the best performance.

3. Reduce Kern. Hz

Kernel's timer frequency ("HZ") in FreeBSD 6.x and 7.x is set to a relatively large value-1000Hz. this was done in attempt to reduce latency in the interim period while some kinks are sorted out and it's planed for it to be converted back to 100Hz in future versions of FreeBSD. high Hz setting has a negative impact on simulated machine's performance because the VM software developed DS a lot of time handling timer interrupts instead of doing real work.

You can change the Hz setting by adding a line likeKern. hz= 100In/Boot/loader. conf. In the extreme cases you might want to use very low values for Kern. Hz like 20, but test first!

4. Disable internal VMware swapping

Consider disabling VMware internal memory swapping and make the Virtual Machine fit in the physical memory of the host for best performance.

5. VMware Tools not necessary

It wocould be nice to have VMware Tools working on FreeBSD but apparently the company doesn't want to support it properly. currently, the only thing that VMware Tools are useful on FreeBSD is to get GUI features like clipboard sharing and automatic mouse focus grab in X. org. VMware Tools on Linux seem to include a driver that does something with memory management, but it's not available for FreeBSD. you don't need VMware Tools for the following things to work: Networking, timer, X. org GUI.

Networking is handled byLeDriver orEmDriver. These two will work without any special configuration of FreeBSD. To use the EM driver, you might need to modify the VM configuration to includeEthernet0.virtualdev = "e1000"Or a similar appropriate line. To use the VMwareVmxnetDriver (which as far as I can see isn' t much different than the Le driver), you need to build a kernel withoutLeDriver first.

Timer issues can be lessened (never resolved, even with VMware Tools) by groupingKern. HzTo something like 50 or 100Hz (inLoader. conf), And installing ntpd.

X. org can use the generic "VMware" display driver which is stored in the default X. org collection of drivers. Mouse, etc. are also handled generically.

The only remaining functionality is the ability to "shrink" drives. If you're running VMware Server on Windows host, there are third party utilities for VMware that can do the same thing.

6. SMP

SMP, at least in VMware Server 2.x, can be useful at least for certain workloads. receivalized Io is slow and it seems slightly slower with SMP so there are no benefits in enabling SMP for IO-driven workloads (either disk, network or something else ). on the other hand it will help with CPU-driven workloads. for example, runningMake buildworld-J2Will make a farily good use of a real hardware 2cpu system, but when running was alized, Io wait is so pronounced it takes at least-J3To avoid long idle times.

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I have never heard of this before and never heard of lnc In the second VMware environment. I have been using lnc and have never encountered any problems. However, I seldom perform network-related tests, try to change lnc to em