• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 6591
  • Last Modified:

VmWare ESX 3.5 Swap file size

I'm still new to the VmWare world and only install ESX 3.5 for the second time today. The server that I installed it on has 700GB of disk space and 20GB of ram. I left the swap file size at the default when I was going through the install which I believe was 500mb or so. Here are my questions 1) Since it have 20GB of ram should I increase my swap file size. 2) Can the swap file size be increased. 3) how may VM show I be able to run on a server with 8 processors, 700GB of disk and 20GB of ram???
1 Solution
Each VM will have it's own swap file. The size of this file will by default be the same as the size of ram allocated for the VM. This swap file will be created when you start the VM.

2) The swap file (and the ram) for the Service Console can be increased to 800MB if you for some reason get short on ram there.

3) You can give a single VM a maximum of 4 vcpus. All your VMs will however be load balanced across all 8 processors. You can also give your VM 700GB disk and 20GB ram if you want:

Regarding this hardware, I think that the disk space will be the limiting factor. How many virtual machines you can run on this host depends on what VMs you're about to create, but to do some maths: If you want to install Windows XP sessions (e.g. to utilize VDI) with each having assigned one CPU and 512MB RAM, you can run about 40 virtual machines on this system.
Assuming further that each XP session has about 15GB of disk space, you're up to 600GB for all the vmdks (left alone the swap files, logfiles, and the ESX server installation itself).
Besides that, having so many VMs on just one physical disk will probably result in slow disk access times as in the worst case, 40 processes are trying to access the disk concurrently.

You can even have a centralized swap store for your ESX server so that all virtual machines use the same swap space, but I wouldn't recommend that if you're going to do snapshots, hot backups or DRS migrations using VMotion etc. with this VMs.

Is using VMCB (VMware Consolidated Backup) or Storage VMotion interesting for you? If so, make sure to have enough free space on your harddisk as in times when the machine needs to be backed up or copied to another data store, it will consume twice as much disk space as usual.
compdigit44Author Commented:
We are not using shared storage at this time but plan on move to one very soon. Here is another question. In ESX 3.5 can I easily increase the allocated hard disk space , CPU count and memory on the fly?
Hire Technology Freelancers with Gigs

Work with freelancers specializing in everything from database administration to programming, who have proven themselves as experts in their field. Hire the best, collaborate easily, pay securely, and get projects done right.

Of what? Of the ESX server itself or of the virtual machines?
The only thing you can increase while running is disk space. Other devices need either that the VM is powered down or that the host is powered down. If you can do vmotion you will see that your guests might get a higher uptime than your hosts because of such things as hw upgrades and/or patching.
First of all you have a monster server! congrats! I'm running ESX server in a proliant DL380 with 8 GB RAM and 2 processors.

You need to plan your VMs to know how many will you deploy. It depends on which will be the workload of each VM (by example a DB Server should have more CPU, RAM and Disk resources assigned than a simple Web Server). Remember that you can assign resources usage (CPU, DISK, MEM and network) in a per-VM basis.

Swap space for the host computer isn't a big issue because its workload will be small. So default swap space will be good. If you want to assign more disk resources to your host server, I strongly recommend that you rebuild your VMWare server and DO NOT select the default partition config and make your own with your desired disk space for the swap partition. It is possible to expand/shrink your VM Swap partition but it will imply lot of effort.
Has this question been answered already?
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Featured Post

Get expert help—faster!

Need expert help—fast? Use the Help Bell for personalized assistance getting answers to your important questions.

Tackle projects and never again get stuck behind a technical roadblock.
Join Now