Mobiles have gotten powerful in recent years. Many browse Inkbunny with one. Of course, being a geek, I'm more interested in serving it with one!
The idea of hosting websites on the same low-power ARM chips used for phones has been building for a while, albeit with many false starts. And when a new technology arises, it's natural to test it on animals…
To this end, I obtained an ARM-based virtual server from RunAbove - a "test lab" division of European and Canadian hosting provider OVH. It was, for a day, handling ~1/20th of Inkbunny's image traffic.
The system in question has a ThunderX 2.0Ghz ARMv8-A core, working out to about 3/8 the processing power of our Virginia cache, at roughly 3/8 the price. It also has 2GB RAM and a 10GB HDD. The RAM is important. Too little memory on a 64-bit node doesn't work out so well. Pair it with too much disk, and you end up barely able to keep the filesystem cached, let alone any of the files, leading to thrashing.
The system runs Ubuntu, which is great, as we use the similar Debian. RHEL for ARM is in development.
The good, the bad, and the ugly
So after a day, what's the verdict? CPU-wise, the system might well be capable of pushing Inkbunny's entire content traffic load (~50Mbit). Our caching software, nginx, is very efficient - and the CPUs have integrated SSL-acceleration hardware, so content encryption isn't a burden.
Would we transfer everything to an ARM-based server? Well, no - we already have dedicated servers in Europe, with CPUs more suited to databases, web servers, or PHP. Scale doesn't help so much here - if it takes a second to generate a page, that's still a problem even if you can do many pages at once.
There's also a reason these servers have four real drives each - a single virtual disk wouldn't keep up. It's fine to be doing hundreds of operations per second if you're the only person using one disk. Having 48 people do the same thing doesn't work so well. (Hosting companies rely on you not all using it at once.)
Still, for use in a private CDN? It'd work, if it were more reliable. We encountered significant networking issues which also appeared to impact disk access (possibly because they're virtual disks). These must be resolved before such systems can be used in production for any length of time. Edit:It was!
Overall, ARM-based servers seem capable of taking on at least low-level tasks. But will this be enough to take market share from Intel? The Xeon D is very exciting; it's something we'd consider for dedicated servers a few years down the line, once they're available for second-hand lease.
ARM may become the norm for the low-end VPS; or it may never be more than a niche product. Either way, we're interested, because we want to get the best value possible for your donations. At a minimum, it forces Intel to compete in product areas previously neglected. Availability of an alternative can be used to extract price concessions by hosting companies, which trickle down to us.
Try it yourself! (no longer available, sorry!)
We have the test box available as the Hamburg Cache (we think it's around there).
RunAbove's ARM-based virtual servers are currently free. That probably won't last (and they appear to have a 100-user limit), but the advertised beta price is $1.13/month, so you'd not be on the hook for much. If you fancy giving one or two a go yourself, here's instructions. Sign up here (SMS required) and you'll get $10 to try out the other services they're offering, such as a VPS with a dedicated disk.