Anne & Lynn Wheeler <[EMAIL PROTECTED]> writes: > when I did the swaptable migration ... i created an abbreviated psuedo > virtual address space for each virtual machine ... primarily so that > the paging subsystem could be leveraged for moving data to/from disk. > basically nearly all control blocks could be copied into this dummy > virtual address space ... leaving only a small stub left in real > storage. at least one of the vm370-based time-sharing service bureaus > got very aggresive with this technique in the amount of resources that > an idle virtual machine had left behind in real storage: > http://www.garlic.com/~lynn/subtopic.html#timeshare
as real storage has gotten larger and larger ... there is less of a need to use control block migration to address constrained real storage limitations (unless really humongous amount of real storage is involved for idle activity). note however, once there is a really aggresive implementation of moving all control blocks to secondary storage ... it was no longer necessary to bring the virtual machine back into the same real processor as it started with (in a loosely-coupled environment). as some of the early vm370-based time-sharing service bureaus went 7-24 with world-wide customers ... they started to encounter issues with scheduled maint. downtime. at least one of them used really aggressive control block migration as basis for moving everything off a processor that had scheduled pm downtime to another processor complex in the same configuration (w/o customers seeing any service disruption). some recent posts mentioning loosely-coupled: http://www.garlic.com/~lynn/2006.html#16 Would multi-core replace SMPs? http://www.garlic.com/~lynn/2006.html#32 UMA vs SMP? Clarification of terminology http://www.garlic.com/~lynn/2006.html#34 UMA vs SMP? Clarification of terminology -- Anne & Lynn Wheeler | http://www.garlic.com/~lynn/
