"Schuh, Richard" <[EMAIL PROTECTED]> writes: > As others have pointed out, accessing an active SFS directory can be > a big contributor. I confirmed this by letting a machine sit idle > for 2 hours while it had such a directory accessed. After 2 hours, I > released the directory and it was disconnected 15 minutes later. In > this case, I would expect to see VTIME incrementing because CMS is > accepting the interrupts. If they are IUCV interrupts, that measure > is blown out the door, too. Is there no such thing as an idle user > anymore?
cp kernel time charge to the virtual machine ... can be anything that the kernel does on behalf of the process. I had originally done the pageable kernel stuff on cp/67 (as an undergraudate) ... by creating a dummy virtual machine id (called system) with dummy virtual address space tables ... into which were mapped all the kernel code. the end of the fixed kernel was identified and then everything else was was allowed to "page". this wasn't shipped as part of cp/67 but was picked up as part of vm370. 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 when idle virtual machine was found, the kernel overhead for moving various control blocks out of storage to disk would be charged against that virtual machine. however, it wouldn't be ongoing ... unless the virtual machine was being periodically woken up for other reasons (and the control blocks had to be brought back and then again removed later). i shipped this as part of the vm370 resource manager. recent post referencing resource manager announcement letter: http://www.garlic.com/~lynn/2006.html#19 DCSS as SWAP disk for z/Linux -- Anne & Lynn Wheeler | http://www.garlic.com/~lynn/
