Hi Doug, >My reason for posting this message is to solicit feedback on the pros and cons >of moving >an existing system to a virtual environment. The IT department at a client >site is pushing >a client to virtualize their 4D system and I've been asked to provide input.
>In a short, my understanding is that 4D can work well in a virtual environment >providing >that the VM is configured for OLTP. The hallmarks of that configuration >appears to be >use of SSD's as the primary drives, apparently acting in a caching function, >and as well >as optimization to support small block transfers (2k? 8k?). It's works great, especially if, as you've stated, sufficient resources are allocated to 4D. That really is the key. Also, make sure that the primary resources are dedicated to 4D. VM is extremely smart and, unless specifically told not to, will divert resources away from 'idle' applications. So if 4D Server is 'quiet' for a period of time, it may 'lose' it's priority with respect to resources (CPUs, caches, SSDs etc) and performance will go down the tube. And it may take 10-15 minutes for those resources to be 'moved' back to 4D Server, once 4D activity resumes. This can be avoided by dedicating resources. The other key is to have lots of experience with VM management and configuration in the IT team. Hopefully, your app is not going to be their first VM. Also, if they say they are doing it to save money on hardware, be very suspicious. Enterprize grade VM hardware is extremely expensive. The savings is in the flexibility, fault tolerance and redundancy it provides. Adding a server is a task measured in minutes rather than days. Moving a server is a completely transparent operation done while the wheels are spinning. It's really quite remarkable. We have a 250 user 150 GB 4D Server fully virtualized. Along with a number of Test and Dev servers. It pretty much just works. One thing we still use hardware for is monthly data file compacts (via MSC). The VM system isn't optimized for that kind of activity evidently. Other than that, it works great. HTH, Tom Benedict Optum This e-mail, including attachments, may include confidential and/or proprietary information, and may be used only by the person or entity to which it is addressed. If the reader of this e-mail is not the intended recipient or his or her authorized agent, the reader is hereby notified that any dissemination, distribution or copying of this e-mail is prohibited. If you have received this e-mail in error, please notify the sender by replying to this message and delete this e-mail immediately. ********************************************************************** 4D Internet Users Group (4D iNUG) FAQ: http://lists.4d.com/faqnug.html Archive: http://lists.4d.com/archives.html Options: http://lists.4d.com/mailman/options/4d_tech Unsub: mailto:4d_tech-unsubscr...@lists.4d.com **********************************************************************
