On Tue, 18 Jul 2006 12:16:16 EDT, Allison said: > 2. How do I make sure that no updates take place in memory from the > time I initiate the snapshot till it is done. Hint: If you're running a program to dump memory, it's going to be calling I/O drivers and so on - and all this activity has to modify at least *some* memory (unless you're on an architecture with a *really* deep register stack ;) You can't ensure that *no* updates take place. At best, you can minimize the number of pages touched. For an example of the kind of hoops you need to jump through, I suggest a careful reading of the 'suspend' and/or 'suspend2' source code - a large part of that code is basically taking a snapshot of memory. Also, you'll need to make sure that whatever software is running that you're trying to snapshot is fairly tolerant of pauses - if you have a disk that manages 20MBytes/second and you have 256M of memory, you're going to be sitting there for 10 seconds. This can come as a surprise to programs that were sleeping on a timer interrupt.. :)
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