Comment by ghshephard | Hacker News Reader

Comment by ghshephard | Hacker News Reader

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The difference between client and server can be a bit grey, but I agree, the distinctions are important. A client is about mobility (small size), low power use (low heat, small battery), and very low latency, focus on human-computer interaction experience.

A server has fewer power concerns, and is all about throughput. Heat, size, are not as relevant (but not irrelevant).

iPhone and iPad are obviously clients. A Mac Pro is a Server. A macbook air is probably a client (though, ironically, it is far more powerful than the $10K servers I had in 1999). A MacBook Pro falls somewhat in the middle, but leans towards client. An iMac is also in the middle, but leans towards server.

I think the angst (which I have to some degree as well) about the distinction between Client vs Server, is because it's not completely clear how to position the Mac Pro and iMac. In some benchmarks, the iMac meets, or exceeds the MacPro. But, in terms of sheer throughput for bulk tasks (Video Rendering), you can get a higher top-line performance from the MacPro. And, for day-day interaction, the 5K Display of the iMac (human-computer interaction), beats out the MacPro.

[edit: 99.99% of the time, downvotes are immaterial to me, but I'm genuinely intrigued in what the contrary opinion is here - I expect to learn something, please share!]

I certainly didn't downvote you, but I don't understand why you'd consider the iMac or Mac Pro as servers. Very few people use them in that fashion.

The iMac has a 5K display. The Mac Pro has two high-power GPUs. These are not server features because they're designed to provide explosive graphics power for a single user at a time. Using '80s terminology, both those Apple computers would qualify as workstations, IMO...

I think an interesting analogy could be made with physical training. Some athletes train for endurance, e.g. running a marathon. Others train for muscle strength, e.g. powerlifting.

A server is an "endurance-oriented computer" -- its power needs to be distributed evenly over multiple active sessions. One remote client can't be allowed to hobble the server.

In contrast, a client is a "strength-oriented computer". For much of the time, it's sitting idle because the human in front of it is so slow. But when the human makes a decision, the computer needs to do its best to fulfill the task immediately (compositing windows, rendering a web page or 4K video effects, etc.)

It's not as simple as that WRT the Mac Pro. One of the graphics cards can't actualy be used to drive displays, it's only there to handle intensive compute tasks.

The Mac Pro also scales to 12 cores. If that's not about distributing power evenly over multiple active 'session' (not sure what 'sessions' are supposed to mean in this context), I don't know what is.

I agree about the iMac though. It is a very powerful computer, but it's clearly optimised for tasks requiring immediate responsiveness. The fact that it also happens to have a very powerful CPU is not the factor that is driving the overall design.

The Mac Pro has those capabilities because it's optimized to be a graphics/video workstation, and those tasks are very amenable to parallelization. Those 12 cores are not there to serve 100 different clients per second, but rather to provide maximum render power for the user sitting in front of the computer. (That's what I meant by a single "session".)

Of course you could put a Mac Pro in a server room or data center, but realistically very few people do that... It's just not designed for that.

There are plenty of large graphics/3D/video render farms, and they don't use expensive workstations like the Mac Pro. You get more bang for the buck by going with traditional server form factors. Cool black cylinders with ridiculous amounts of desktop-oriented I/O don't make ideal servers.

Ironically, given your definition, a Mac Mini, which is about 1/4th to 1/8th the power of a Mac Pro, would be considered a server. There are even Data Centers (MacMini Colo) that are dedicated to shelving Mac Mini's for such a purpose.

Perhaps the whole "Server/Workstation/Client" segmentation doesn't make sense after all.

When I try and differentiate a "client" from a "server" - I usually think in terms of "Display/Interact" versus "Processing/Transacting" - the more emphasis there is on displaying, and interacting with the user, the more I consider it a client. The more emphasis there is on "Processing/Transacting" - the more I consider it to be a server.

But, you are right - there is an interesting middle ground that I did not consider - the device that is designed to simultaneously do massive amounts of processing/storing/transacting while interacting with the user. Workstation should probably enter the nomenclature - but then things get very grey - your average 2013 MacBook Air is more powerful than any workstation any engineer in the world had in 1998. Does this mean the only difference between client and workstation is comparison with it's peers? And, a client today, is a workstation 15 (heck, maybe only 10) years from now?

"Client" and "Server" has nothing to do with the form factor of the device. It's a designation of roles. Typically, servers 'provide' and clients 'consume'.

Bingo.

The terms are self descriptive: Servers serve, clients request. So I don't understand why anyone would bring form factors into the equation. Particularly when it's well documented that you can turn anything into a server (old laptops / desktops, developer boards such as the Raspberry Pi, etc), and equally a server can act as a client (eg server-to-server API calls)

Being a server is not about power, a $5 Digital Ocean VPS is a server and it has way less power than Macbook Air you mention as a client. The only thing about a server is that it serves to non local user(s) - it could be could be low powered ARM based RPi or a multi-core Intel thing, it really just depends on it's workload. The Mac Pro is designed as client and same for all current Macs (they don't sell a server anymore), which is how they are typically used.

A server usually offers some kind of service to other computers over a network and runs an OS optimized for that (different scheduler, for example). Neither Mac Pros nor Macbooks are designed for that, so they are clearly not servers.

the notion of client and server is dependant on the kind of application. For a single player game, an Ipad is both a client and a server.

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