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No one "needs" a particular architecture. It's just that some of them are better suited to certain problems than others. If you really want to get rid of some

No one "needs" a particular architecture. It's just that some of them are better suited to certain problems than others. If you really want to get rid of something and "move on" why not get rid of the wild class of devastating speculation bugs that every OOO processor in existence currently has? Far more valuable than worrying about how instruction bits are arranged in a stream.

zamadatix 2y ago
The main problem with non-speculative options isn't hardware it's performance. You can turn x86 CPUs into in order machines without respinning hardware. Nobody wants to do it because it's slow as molasses. If there was a completely alternative design that was better than speculative execution wholesale then it'd be back to being the original "just go to the fastest thing".
Atotalnoob 2y ago
Yes people need a particular architecture. There are many legacy systems that still rely on IBM chips, mainframes, etc. They can’t just move on without rebuilding the entire system from scratch. a monumental and risky proposition. Even if tomorrow everyone went all in on arm, risc5, whatever, x86 is here to stay.
CamperBob2 2y ago
why not get rid of the wild class of devastating speculation bugs that every OOO processor in existence currently has? Because almost no one but cloud-computing providers have a threat model that justifies the performance hit (and, not coincidentally, the carbon footprint) associated with crippled CPUs.
- immibis 2y ago
  Laptops could do with the power use reduction.
  - epcoa 2y ago
    Speculative execution like almost every modern CPU performance trick decreases power use. Mobile SoCs have OOO.
  - School-Cotton 2y ago
    I think you are underestimating how many times slower processors would be without any speculation at all. It would mean having to wait dozens of cycles on every branch so you can know whether it was taken before executing the next instruction, for example.
School-Cotton 2y ago
If anyone knew how to get rid of all the speculation bugs, don’t you think they’d do so? What concretely are you proposing Intel and AMD do?

zamadatix 2y ago

The main problem with non-speculative options isn't hardware it's performance. You can turn x86 CPUs into in order machines without respinning hardware. Nobody wants to do it because it's slow as molasses. If there was a completely alternative design that was better than speculative execution wholesale then it'd be back to being the original "just go to the fastest thing".

Atotalnoob 2y ago

Yes people need a particular architecture. There are many legacy systems that still rely on IBM chips, mainframes, etc. They can’t just move on without rebuilding the entire system from scratch. a monumental and risky proposition. Even if tomorrow everyone went all in on arm, risc5, whatever, x86 is here to stay.

CamperBob2 2y ago

why not get rid of the wild class of devastating speculation bugs that every OOO processor in existence currently has? Because almost no one but cloud-computing providers have a threat model that justifies the performance hit (and, not coincidentally, the carbon footprint) associated with crippled CPUs.

immibis 2y ago
Laptops could do with the power use reduction.
- epcoa 2y ago
  Speculative execution like almost every modern CPU performance trick decreases power use. Mobile SoCs have OOO.
- School-Cotton 2y ago
  I think you are underestimating how many times slower processors would be without any speculation at all. It would mean having to wait dozens of cycles on every branch so you can know whether it was taken before executing the next instruction, for example.

School-Cotton 2y ago

If anyone knew how to get rid of all the speculation bugs, don’t you think they’d do so? What concretely are you proposing Intel and AMD do?