Can anyone give some insight on the performance impact of enabling Shadow Copy on a file server? We have a volume that has about 700 GB of data on it, used by 100 users. There isn't a really high load for changing files, but many reads.
Shadow Copies can only be enabled on the same volume due to size, and lack of alternative drives. Does having the source and storage area on the same drive severly impact performance? I know the documentation says it will, but I'm looking for real world examples.
Best Answer
I've got a similar situation (more data less uses - around 60) and the benefits of having shadow copies available to undo mistakes is invaluable. That being said your question was about performance.
Microsoft doesn't say much about it because it's quite subjective. With mostly reads you probably wont notice anything. NTFS uses copy on write to achieve snapshots. (akin to zfs if you've heard their marketing) Which means for each write to an existing file it has to write a new block and make a note about the old block being old. I've got most of my servers on a raid 5 or 6 setup so I don't notice the extra writes. On a single spindle you might.
I also use the snapshots for backup purposes, I don't need to worry about open files etc. A lot of different backup utilities (ghost, true image, and possibly Microsoft backup) leverage this.
There are so many other variables to network share performance (network, cpu, application) snapshots weren't noticed by any of our staff. Until they did did something stupid with a file that is.
It is possible to turn snapshotting on and then turn it off again later if there's a problem. So it's worth a try.