Huang, Ying wrote: > On Mon, 2007-08-27 at 09:28 +0800, Hu, Fenghua wrote: > >>One quick question is, can it improve hiberation/wakeup time? > > > In general, for kexec based hibernation, what increases > hibernation/wakeup time: > > - One extra Linux boot is needed to hibernate and wakeup. > > > What decreases hibernation/wakeup time: > > - Most hibernation/wakeup work is done in full functional user space > program, so it is possible to do some optimization, such as parallel > compression. - It does not have to reclaim pagecache before suspend? - It does not have to restore working set afterwards? (You could do this to reduce image size, of course, but it can be optional which is nice). > So, I think the kexec based hibernation may be slower than original > implementation in general. In this prototype implementation, the > hibernation/wakeup time is much longer than original hibernation/wakeup > implementation. But it has much to be optimized and I think it can > approach the speed of the original implementation after optimization. Also, don't just look at the time to do a simple suspend/resume cycle, but the full cost of going from working state to working state (eg. grep a kernel tree or two!). Although the kexec details are out of my league, I really like everything about the concept :) Nice work. -- SUSE Labs, Novell Inc.
