On Thu, 2003-08-14 at 13:26, Carpenter, Mark wrote: > Problem: In a shared disk environment, changes made by the owner (R/W) are > not seen by R/O sharers in a timely fashion. This is especially problematic > when the Linux virtual machine has a sizable virtual memory size allowing it > to have lots of buffercache. In small memory Linux images, the changes are > recognized fairly quickly, you can force by editing a sizeable file which > will cause the buffercache pages to be re-used (stolen).
This is why I recommend having a pair of master images, updating them one at a time, and manipulating directory entries so that the guests always have a view of one or the other, and scheduling logoff/reipls so that they pick up the changes in a controlled fashion. It's reasonably easy to script the directory change process. However, it doesn't let you do it on the fly and I don't think there's a good way to do that. At least if there is I don't know about it. Adam
