On Wed, Sep 04, 2002 at 06:32:17PM +0200, Phil Payne wrote: > > The redpaper for cloning zLinux images by using VQDIO is available from > > http://www.ibm.com/redbooks/abstracts/redp0301.html. This redpaper is based > > from the LinuxWorld zLinux cloning example (using IUCV) that I released in > > 5/5/2002 (http://www.vm.ibm.com/devpages/chongts/tscdemo.html) . Have Fun!
> Quick 'analyst' question (I'll download and read it when I have the > time, but not until next week at the earliest): > Roughly how quickly could a new Linux image be established using > this technique on, e.g., a z800? I don't know yet, not having read the paper. However, using a VQDIO Guest LAN on a z900 (31-bit mode), and sharing /usr but nothing else, it was taking us (when the machine wasn't doing anything else much) about 3 minutes. Almost all of that was spent copying /; if we had had FlashCopy or something like that, I'd guess, based on the way we did it, which relied on DIRMAINT and 2 IPLs on Linux per guest (first time it comes up generic; it uses CMSFS to read stuff the cloning process put on its 191-disk to determine hostname, IP address, etc., and then write that onto the real filesystem and reIPL) about 30 or 45 seconds. If raw speed is what you care about, you precreate a small inventory of machines, and hand those out on demand. As you IPL each one the first time, it can send a message indicating you need to refill your inventory. Then it turns into the time to IPL a Linux guest, typically (if few services are running) twenty seconds or so. Adam
