←back to thread

204 points WithinReason | 1 comments | | HN request time: 0s | source
Show context
mrweasel ◴[] No.40715746[source]
An once that becomes generally available operating systems will eat the bandwidth in an instance and any speed-up to be gained on a desktop will be completely negated.

It seems like we're stuck at a pre-set level of latency, which is just within what people tolerate. I was watching a video of someone running Windows 3.11 and notice that the windows closes instantly, which on Windows 10 and 11 I've never seen there NOT be a small delay between the user clicking close and the window disappearing.

replies(5): >>40715815 #>>40716021 #>>40716089 #>>40716389 #>>40717169 #
eqvinox ◴[] No.40716089[source]
> It seems like we're stuck at a pre-set level of latency,

Bandwidth isn't latency, and PCIe 7.0 running as fast as 128 GT/s is no statement at all about its latency. I remember this great analogy from university: a truck carrying a full load of backup tapes across a country has amazing bandwidth but atrocious latency.

(I still agree with your sentiment, just PCIe is not one of the problems in this regard. The connection between bandwidth becoming available and being eaten up vs. latency is a red herring; it's all about properly engineering software for responsitivity.)

replies(2): >>40716402 #>>40716632 #
szundi ◴[] No.40716402[source]
If your Win27k startup is a 8k 120fps video of a butterfly transforming to a windows logo - then it is latency

Btw all bandwith is built to reduce latency, aren’t they. Bit philosophy heh

replies(2): >>40716686 #>>40716931 #
retrac ◴[] No.40716931[source]
Latency and bandwidth are often in tension. (And guaranteeing low latency can eat up a big chunk of theoretically available bandwidth, due to overhead.)

The canonical example is probably a dial-up modem or other slow link between two locations. The latency is under 1 second to send one byte over the modem. But it's probably faster to just ship a hard disk if you want to send 100 gigabytes from one location to the other, even though the latency might be hours or even days, until the first byte arrives.

In practice, you can send lots of tiny little packets with lots of overhead (but low latency) or you can send lots of big heavily buffered packets with low overhead (but with high latency).

This is why multiplayer game protocols often consist of a constant stream of tiny UDP packets containing events like "character moved 40 nits east at game time ..." or "character fired weapon at game time ...." Even a 10 kilobyte bulk state update is going to cost at least a few milliseconds, more probably tens or even hundreds of milliseconds over some wireless connection. And that's a very noticeable lag.

replies(1): >>40720712 #
1. Dylan16807 ◴[] No.40720712[source]
Another good example is the memory in your computer. DDR is much lower latency, and GDDR is much higher bandwidth.