When was the last time you bought a 32 bit PC?64-bit CPUs have been around longer than Ubuntu has
What do you miss most not having a 64 bit OS on the RPi?
Not so. I was already bitten by 32 bit processors and working with time five years ago.Calm down, you've got until 2038 before you need to say goodbye to 32bit
I have been compiling GCC, Linux kernels and a whole lot more since 1996 when 1GB of RAM was a lot!One of the problems with kernels and compilers is the hardware needed to compile them is normally bigger than Pi's.
Not really. I suspect you will find all new phones and tablets are 64 bit ARM. ARM would only laugh at you if you told the they need not bother with 64 bit cores when they are doing so well with them.32-Bit rules, especially when talking ARM.
Show me an OS that can make us of 16TB or even 32GB of address space on a 32 bit machine. Even Raspbian on the Pi 4 need some address space extension hack (I forget what it is called) to access 3.2GB of RAM from a process. Which slows things down apparently.With the ARM MMU you have up to 16TB ..
I guess you are just not working with big data sets. A few gigs is small for a database, being able to map a lot of data to the address space makes the DB software easier to write and faster.If I ever need more than 16TB of RAM something is wrong. If I ever need to have more than 3.8GB Mapped in to a single applications work space at one time then something is wrong.
Where on Earth did you get that statistic from? I guess you made it up.For that matter about 45% of applications could do just as well with only 16-bit integer math and logic,
My view is:That is just my view, take it or leave it.
Sure, why not. Raspbian is basically Debian and Debian has been able to support 32 bit binaries on 64 bit machines since forever. At least on x86, no idea how well it works on ARM but I suspect it's fine.I see Raspian following in the SyWoW64 solution to keeping 32 bit relevant in a 64 bit world.
I agree, I paid for them, I want them working hard for me.I hate the thought of all those transistors in the SoC sitting around doing nothing
These gains might be more than expected on the Pi4.
Its common to mix high power Cortex-A72's or A73's with the low power A53's in the same SoC - called big.little
I think the two ISA's are completely compatible. I have compiled large programs for the A72 and run them on the A53 and vice-versa.
If you have "a = b + c" and then "d = a + 4", the second addition has to wait for the first to complete, so that a value for "a" is available..No idea what that out of order stuff is needed for?
Yep. ARM cleaned things up and made the ISA more performance friendly. Basically they learned lessons from their mistakes, and the mistakes of other RISC vendors (MIPS had pipeline delay slots that the programmer/compiler had to think about to get performance, which did not work out). They learned the same lessons that Berkeley did and have put to use in the RISC V ISA design.These gains might be more than expected on the Pi4. In 64-bit mode it runs a different instruction set ...
Something may have been a dream but the original ARM was focused on performance. The performance one could get from going to a RISC architecture. It was the fastest processor one could get in a desktop computer at the time. But as you say, lessons have been learned over the decades.The 32-bit ARM instruction set was designed long long ago before the new high performance cores were even a pipe dream.
Ha! I bet DavidS will have something to say about that. He'd be wrong mind.Features like being able to randomly write to the IP, conditional execution of almost anything, etc are just bad news nowadays.
Think about going to the supermarket with your wife's shopping list. You probably hate shopping as much as I do so you want to get it done as fast as possible and get out of there.No idea what that out of order stuff is needed for?
It can be done, and is. The A53 runs 64-bit A72 targeted binaries.
Exactly. The A53 is designed for low power consumption and efficiency. (But it does have hardware multiply and divide which I think might save power compared to slow library functions).
Oddly, for my Odroid-N2 which is 4 x A73 (big) cores and 2 x A53 (little) cores, the big cores run at 1.8GHz and the little cores run at 1.9GHz. Not sure why that is.
You can image how hard conditional execution is to implement in an out-of-order CPU.
Indeed. The most compelling argument for 64-bit is that others have jumped on the 64-bit bandwagon leaving 32-bit no longer supported.
That's a bug in OpenSSL, nothing to do with whether the machine itself was 32 or 64bit.Heater wrote: ↑Thu Jul 04, 2019 5:25 am@Imperf3kt,Not so. I was already bitten by 32 bit processors and working with time five years ago.Calm down, you've got until 2038 before you need to say goodbye to 32bit
I was trying to create security certificates with OpenSSL. The certificates were created but did not work in my VPN. After a day or two of investigation I found my certs we being created with an expiry date some time in the past. They were created expired! I gave up messing with that, but some time later I discovered my same procedure created valid certificates when used on a 64 bit machine. After more investigation back on the 32 bit machine I found that because I had set the certs to expire in 40 years time, which is after 2038, some time calculation in OpenSSL had overflowed resulting in an expiry date in the past. Sometime later I found this had been reported as a bug in OpenSSL and fixed.