News for hackers. Stuff that matters.
Re:Clocking a 6502 simulator to 15GHz by duskwuff on Monday April 13, 2020 @06:31PM (#22860915)
18 MHz, actually -- the FPGA clock speed is 73 MHz, but it executes the equivalent of one 6502 clock cycle in four of its clocks.

That being said, this was implemented on a budget-line FPGA from 2006 (XC3S50A - a small Xilinx Spartan-3A). A modern performance-line FPGA would probably hit a couple hundred MHz easily.

Re:Clocking a 6502 simulator to 15GHz by baybal2 on Monday April 13, 2020 @07:34PM (#22861345)
It's still surprising how little relatively to the level of perceived performance have IPC count improved since seventies.
Re:Clocking a 6502 simulator to 15GHz by cmrdporcupine on Monday April 13, 2020 @09:55PM (#22862059)
It seems to me that computational throughput has improved exponentially, but latency for input tasks etc. has in fact worsened in many cases.
Re:Clocking a 6502 simulator to 15GHz by aidenn0 on Monday April 13, 2020 @10:55PM (#22862333)
Per TFA IPC has improved by about factor of 5, assuming a 3GHz machine runs BBC micro at equivalent performance of 15GHz
Re:Clocking a 6502 simulator to 15GHz by vardump on Tuesday April 14, 2020 @06:22AM (#22864332)
Reality for (SIMD) integer math is probably closer to 1000, floating point... probably 100000.
Re:Clocking a 6502 simulator to 15GHz by raverbashing on Tuesday April 14, 2020 @02:35AM (#22863274)
You're wrong :)

IPCs for 6502 or Z80 (4x "faster" clock but 3-6 cycles per machine cycle) processors were at the count of clock cycles per instruction

Even a measly 386/486 were much faster than that.

Enter the Pentium with the ability to execute 2 instructions in parallel.

IPC count were the big gainers recently as well

Re:Clocking a 6502 simulator to 15GHz by baybal2 on Tuesday April 14, 2020 @02:45AM (#22863312)
It is still only 20-30 fold at max on average. So much more came from many thousand fold clock speed increase, and much wider execution paths.
Re:Clocking a 6502 simulator to 15GHz by nikanj on Monday April 13, 2020 @09:36PM (#22861985)
The perceived performance for an average desktop has been pretty stagnant since, I don't know, at least the mid-nineties.
Re:Clocking a 6502 simulator to 15GHz by ajuc on Tuesday April 14, 2020 @12:27AM (#22862747)
There was a huge perceived improvement when SSDs first appeared.
Re:Clocking a 6502 simulator to 15GHz by spullara on Monday April 13, 2020 @09:42PM (#22862008)
Softare expands to fill the CPU available.
Re:Clocking a 6502 simulator to 15GHz by woadwarrior01 on Tuesday April 14, 2020 @12:18AM (#22862705)
AKA Wirth’s Law[1]: “Software is getting slower more rapidly than hardware is becoming faster.”

[1]: https://en.m.wikipedia.org/wiki/Wirth%27s_law

Re:Clocking a 6502 simulator to 15GHz by FeepingCreature on Tuesday April 14, 2020 @06:14AM (#22864271)
Software is being produced faster though.
Re:Clocking a 6502 simulator to 15GHz by 6510 on Tuesday April 14, 2020 @01:22AM (#22862976)
Didn't cars also follow that pattern?