As a lover of fine cuisine, I am always struck at the difficulty of choosing between a tasting menu and a massive steak. The tasting menu is about sampling a little bit of a lot of things. The chef is trying to maximize the number of unique flavors over calories. Whereas when you eat a steak you are trying to maximize the number of steak calories.
Tasting menu is about doing a lot of little things.
Steak is about doing a lot per thing.
And that is a very crude analogy about the difference between storage and networking.
If we consider a packet a unit of work, storage systems expend a lot of resources per packet as compared to network devices and so process vastly fewer packets.
Storage system architecture must optimize the use of very slow devices. The slower the device the more computation value you get out of clever algorithms on a per packet basis if they can avoid going to disk. So storage uses complex in-memory data structure with complex algorithms that blow out data caches because storage systems have to. The reason flash was so disruptive to the storage industry is because the amount of computation per packet became less as the performance of flash closed the CPU vs storage performance gap.
Network system architecture must, on the other hand, do the minimal amount of work because it is inherently slowing down the flow of electrons. A beam of light down a cable that hits a network device feels like it went from light speed to impulse speed. As a result networking systems must do heroics to minimize the amount of computation and simultaneously make the computation go as fast as possible.
Practically what this means is that a network system can benefit hugely from custom specialized computational hardware whereas storage can not.
In English: ASIC for networking making sense, no one uses anything but Intel CPU for storage. And every company that tried to use custom hardware in
storage.
This answers a long standing question I had, as to why storage companies never used custom computational hardware and networking companies did.
It also answers why server companies go after storage and not networking: the hardware server companies build is more aligned to a storage problem than a networking problem. For example Sun and Dell and HP went after storage in a way they never went after networking.
This also answers the mystery Cisco. Much like Intel won the server CPU war, a single dominant player can emerge in networking given the need for custom hardware. At some point in time only a small number of players can play the game.
And last it answers the software defined storage mystery. In software defined networking we move control out of the hardware device. Software defined storage just says I can run control and data path code on any piece of hardware… This is an important distinction that is not obvious.
Coolness.
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