Once a file grabbed from another ZZFS device is modified, the original is updated to reflect any changes. One advantage of ZZFS’s design is that data is downloaded even while devices are powered down. “If I’m switching between my laptop and tablet, and close the laptop, they’re never on at the same time,” says Mazurek. “If my data was on the cloud, I might have to wait a while for that data to come down.”
The researchers plan to create apps for phones and tablets; because those devices are rarely switched off, such apps could easily act like a PC equipped with one of the Somniloquy network cards, said Mazurek.
Although ZZFS manages to sync files without relying on the cloud, trials have shown that grabbing data from a sleeping device can take around 20 seconds because it takes a while for a Somniloquy card to wake a device. Mazurek acknowledges that this isn’t exactly speedy, but if data is crucial, then a short wait might be worth it. If ZZFS were proactive in fetching, say, music files, it could allow playlists of media from remote devices to play without a hitch, she said.
As Intel and other PC makers push laptops to become more like tablets, rapid startup times and “instant” waking from sleep have become important features for new PCs. “We think this [startup time] is coming down. Newer systems are on the order of 10 to 15 seconds to stand by and then resume, and we think that’s going to improve,” she said.
Yuvraj Agarwal, a researcher at the University of California, San Diego, led the original work that created the Somniloquy design, originally intending it as a way to save energy. But he believes the general design could become commercial reality, citing the way laptop manufacturers have experimented with “instant on” modes that rely on separate, low-power systems not unlike Somniloquy.
“There were some laptops that had a separate ARM processor with a completely different OS, such as Linux, in addition to the main system running Windows, which provided a mechanism to fast-boot and check e-mail, etc., quickly at lower energy,” explains Agarwal. “These two separate systems are of course not integrated together, as Somniloquy proposes, but you are starting to see a bit of this.”
Agarwal is currently working on a software-only version of Somniloquy called SleepServer that has centralized servers stand in for many sleeping PCs to save energy in buildings.