My views:
A page fault's expense seems to vary quite a bit among architectures/processor and also the entire system setup and assumptions on VM system. x86 architectures aren't too good at it and Linux is quite x86 minded. Sure, there aren't many other relevant architectures these days. Also, these days, VM systems aren't used today as they were back when they have been designed. Back in 1988 or 1990 (or before), a typical Unix/BSD system would often page all the time - RAM was never enough - and page in small memory portions. Today, RAM is also not always sufficient, but if not - usually one or some large process(es) gets paged out - usually doing something related with media files or other interactive stuff. For me, COW was a quite efficient overall aproach. Maybe there are some more efficient but less general aproaches around, and maybe a general purpose VM strategy would be different if designed today having all the current hardware setups in mind (and not 20 years ago). This doesn't make someone else an idiot.
h.
If someone releases bench marks, of course the results are "optimized" - as if you do statistics with a goal in your mind or whatever biased undertaking. You'd optimize compilers, maybe even the integer unit designs.
Point is, however, what's the big deal ?
is there any objective benmark out there anyway ?
do you cheat 5% ? Is it 10% or 25% ?
Well, guess it's more like 5-10% at the most.
So, who cares ? Do you notice the speed difference that was presented maybe inaccurately ?
h.
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My views: A page fault's expense seems to vary quite a bit among architectures/processor and also the entire system setup and assumptions on VM system. x86 architectures aren't too good at it and Linux is quite x86 minded. Sure, there aren't many other relevant architectures these days. Also, these days, VM systems aren't used today as they were back when they have been designed. Back in 1988 or 1990 (or before), a typical Unix/BSD system would often page all the time - RAM was never enough - and page in small memory portions. Today, RAM is also not always sufficient, but if not - usually one or some large process(es) gets paged out - usually doing something related with media files or other interactive stuff. For me, COW was a quite efficient overall aproach. Maybe there are some more efficient but less general aproaches around, and maybe a general purpose VM strategy would be different if designed today having all the current hardware setups in mind (and not 20 years ago). This doesn't make someone else an idiot. h.
If someone releases bench marks, of course the results are "optimized" - as if you do statistics with a goal in your mind or whatever biased undertaking. You'd optimize compilers, maybe even the integer unit designs. Point is, however, what's the big deal ? is there any objective benmark out there anyway ? do you cheat 5% ? Is it 10% or 25% ? Well, guess it's more like 5-10% at the most. So, who cares ? Do you notice the speed difference that was presented maybe inaccurately ? h.
this doesn't look like an alternative to me