[marcosdumay]

> But it also makes rendering each single character a lot more complex.

Not millions of times more complex.

Except for some outliers that mess up everything (like anything from Microsoft), almost all of the increased latency between keypress and character rendering we see on modern computers comes from optimizing for modularity and generalization instead of specialized code for handling the keyboard.

Not even our hardware reacts fast enough to give you the latency computers had in the 90s.

[Borg3]

Im not really sure what are you talking about ;) HW become much much much faster. Mostly in speed of computing, but latency also dropped nicely. The letency bloat you see its 99% of software (OS). I still run Win2003 on modern desktop, and it flies! Really, booting/shutdown is quick. Im on spinning rust, so first start of webbrowser is slowish a bit, but once cached, its like 200ms-500ms depending on version (more modern = slower).

[marcosdumay]

Take a look on the latency of a keypress on your modern keyboard to when your CPU has the chance to first process the data, you'll be surprised. Depending on how your hardware is configured, it can reach 100ms there alone.

Your mouse has an equivalent issue, except that it's not usually optimized to the same level, so the worst case is way more common. Audio has a much worse issue, and can lag a large fraction of a second on hardware alone. And there's the network, that has optional features that are emulated by adding lags proportional to the bandwidth.

All of our hardware has become more capable with time, but that doesn't mean latency has decreased. Some kinds of latency have gone down, others have gone way up.

[Borg3]

Okey, yes.. Its a mix of HW/OS issue indeed. I remember my old gaming rig I assembled more than 10 years ago. Asus mother board, i5-760 CPU, ATI HD 6850. Win2003 as OS. All was tuned and it was really great. Basic DPC latency was around 30-40us. Under load it increased slighty but it was always <100us.

Now catastrohpic (with I didnt knew at that time) event occured. After 10 years, Internal NIC burnded. I was like, okey.. I have dozens of PCI NICs, lets plug one and vioala. And I did. But, there was problems, after a while (hour or so) I noticed Audio glitches, especially when when there was network activitiy. After more investigation and reading mobo manual I noticed that IRQs were nicely spread for all internal mobo components + PCIe x16 bus. Other PCI ports were always shared one or another. I could do nothing to fix it.

PC now catch dust, I bought used HP 8200 PC with works nice, but its not gaming rig, standard DPC latency is around 2000us, with is quite large.. Still, for normal use that latency is great, Im very sensitive to lag and latency so if I had issues here, I would be mad.

At the end, some pics from my DPC stall fight:

http://ds-1.ovh.uu3.net/~borg/pics/DPClat.png

http://ds-1.ovh.uu3.net/~borg/pics/DPC_stall.png