Jim Lawrence
accessd at shaw.ca
Sun Jun 28 01:09:46 CDT 2009
Impressive John... all those nice new toys as well... I hope I do not sound too jealous. ;-) ...but there is many medium companies who do not have the hardware you do. Jim -----Original Message----- From: accessd-bounces at databaseadvisors.com [mailto:accessd-bounces at databaseadvisors.com] On Behalf Of jwcolby Sent: Saturday, June 27, 2009 8:10 PM To: Access Developers discussion and problem solving Subject: [AccessD] Running four VMs on Windows 2003 Server I finally got around to fixing the issue I was having running multiple VMs on my Windows 2003 X64 servers, now running 16 gigs of ram. The first problem I was having which was a real b****to solve was that the VMs simply would not connect to the network. It turns out that I had Hamachi installed on the server. Apparently what happens is that hamachi installs a new NIC and all that stuff and now when the VMs fire up they grab the Hamachi NIC instead of the physical NIC. As soon as I uninstalled Hamachi that problem went away. BTW I have been googling this problem for MONTHS and finally found this tip as the very last post in one of the threads about VMs not connecting. So... I now have four VMs running, each VM with three gigs of ram. I run a specific software package which does address validation. A couple of weeks ago I bought a new Vertex Solid State Disk: http://www.newegg.com/Product/Product.aspx?Item=N82E16820227393 I create four partitions on that and then assign one of the partitions to each virtual machine. I then copy all of the database files that Accuzip uses for the address processing. These files are read-only BTW. I used to use an iRam (hardware) RAM disk with 4 gigs total, and do the same thing, partition it into four 1 gb partitions and give each VM a partition. That worked for one VM but the performance was awful for any more than that. The iRam has a total bandwidth of about 125 gbytes / sec (it was SATA I) and it just wasn't up to the job. Just as a benchmark, I was getting about 1 million records / hour running on a raid 6 disk array, so even the iRam was a big improvement, at least for one instance. At any rate, I would get about 2.5 million records / hour processing in my one VM using the iRam. Using the new SSD I get about 4.1 million records per hour, and I am getting that in FOUR virtual machines running simultaneously! I upgraded one of my servers to the new AMD Phenom II X4: http://www.newegg.com/Product/Product.aspx?Item=N82E16819103471 And on that machine, running only one VM (and using that SSD) I achieved about 6.4 million records / hour. That processor is about 40% faster so it makes sense that I would get a much higher records / hour. I am going to order a new processor for the server that I am setting up as my VM server and see if I can jack the four VMS up to something close to that rate as well. 'Twould be nice if that happens! I originally had SQL Server running on this machine and had assigned 7 gigs to it. With four VMs trying to use 3 gigs each, performance on the VMs slowed to worse than a crawl. Once I remembered that SQL Server was there, I stopped the service, stopped all of the VMs, closed the VM host software, reopened the host and reopened all of the VMS and the performance is stellar. The thing to understand is that I often have to validate tens of millions of records. My total processing time for a two million record chunk was about 40 minutes on the faster machine so to do 50 million records (25 files) would take most of a 24 hour day. If I can split those 25 files out over four machines I will drop the total turnaround down to a more reasonable 6 hours or so, especially if I can get the faster processor going on the VM server. I will be a happy camper. -- John W. Colby www.ColbyConsulting.com -- AccessD mailing list AccessD at databaseadvisors.com http://databaseadvisors.com/mailman/listinfo/accessd Website: http://www.databaseadvisors.com