64 bit OS Raspberry Pi4 Benchmarks • Hacker News Board

Re: 64 bit OS Raspberry Pi4 Benchmarks

#51

Post by RyJones » Sun, Mar 01, 2020, 3:54 AM UTC

4d617832 wrote: post #21

rgovostes wrote: post #19

One of the things that I find great about Raspbian is that the boot files are stored on a FAT32 partition which is readable from any OS, and there are some nice considerations for headless setups: drop in a wpa_supplicant.conf to configure Wi-Fi, `touch ssh` to get OpenSSH enabled at next boot. Do any of the alternative OSes, like Ubuntu, offer this?

So that's how they came up with that. As someone who normally installs "normal" Linux systems I find it quite irritating that you have to put a file somewhere, especially the boot record, to "enable" ssh of all things. Up until now I considered it a weird decision. (and I still think it is not optimal) I deploy my RPi's in the field and don't put a monitor on them so I would expect ssh running as default. First time…

Have you considered something like Yocto[0]? I've had good luck with it.

[0] https://jumpnowtek.com/rpi/Raspberry-Pi-Systems-with-Yocto.h...

Re: 64 bit OS Raspberry Pi4 Benchmarks

#52

Post by foxrider » Sun, Mar 01, 2020, 4:20 AM UTC

proverbialbunny wrote: post #36

4d617832 wrote: post #30

Earlier quoted context omitted.

Probably the right decision then. As I don't put them on public networks and delete the pi user this is of little concern to me, but given the target group, it is a simple safety measure.

I think there is a better solution: On a new install on first login, over ssh or on the gui, a user/password must be created. This way the initial login only works once. Both gui user/pass and ssh user/pass are tied by default.

This is how it works in ARMbian. It forces a password change on first login. It can be annoying if you intend on deleting the alarm user right after that, but I can easily see why. "Default" passwords are always suboptimal.

Re: 64 bit OS Raspberry Pi4 Benchmarks

#53

Post by runamok » Sun, Mar 01, 2020, 4:39 AM UTC

Maxious wrote: post #28

4d617832 wrote: post #21

Earlier quoted context omitted.

So that's how they came up with that. As someone who normally installs "normal" Linux systems I find it quite irritating that you have to put a file somewhere, especially the boot record, to "enable" ssh of all things. Up until now I considered it a weird decision. (and I still think it is not optimal) I deploy my RPi's in the field and don't put a monitor on them so I would expect ssh running as default. First time…

Raspbian did originally come with SSH enabled by default but the default credentials pi/raspberry made it trivial for misuse: https://www.zdnet.com/article/linux-malware-enslaves-raspber...

Exactly. You can't have it both ways: make it easy to remember the user/pass and also make it easy to login remotely.

Re: 64 bit OS Raspberry Pi4 Benchmarks

#54

Post by cellularmitosis » Sun, Mar 01, 2020, 4:40 AM UTC

m4rtink wrote: post #35

gok wrote: post #26

One downside: you will probably need a bit more memory to do the same work. An unmentioned benefit: better ASLR, for what that's worth. > A 64 bit system means that RAM can be accessed in 8 byte read/writes per instruction. I mean...kind of but that's probably not really what's happening in this benchmark. Firstly, in that test `memset()` is surely using NEON instructions internally on both ARMv7 and AArch64, which c…

I wonder if using zram or zswap can help "eat" those overly long pointers in RAM via compression ?

I've never understood why zswap decompresses the pages before writing them out to disk. Disk IO is the slowest part of the whole chain, you've already paid to compress the data, why on earth would you throw that away AND use up more disk IO?

Re: 64 bit OS Raspberry Pi4 Benchmarks

#55

Post by slumos » Sun, Mar 01, 2020, 5:15 AM UTC

joecool1029 wrote: post #50

guug wrote: post #42

Earlier quoted context omitted.

Can you cite a source for this claim?

Why yes, yes I can: https://www.raspberrypi.org/forums/viewtopic.php?t=252369#p1...

> this will be combined with a 32bit userland, for the reason mentioned above. - the amount of work needed to update all the libraries that talk to the GPU.

Re: 64 bit OS Raspberry Pi4 Benchmarks

#56

Post by CivBase » Sun, Mar 01, 2020, 6:09 AM UTC

Noob question: What kind of optimizations are even responsible for those kinds of performance improvements?

32 bits is enough to utilize all 4 GB of the Raspberry Pi4, so I figured the only benefit of using a 64 bit OS would be to support 64 bit software. Why would a 64 bit build perform better than a 32 bit build on the same hardware?

Re: 64 bit OS Raspberry Pi4 Benchmarks

#57

Post by wrboyce » Sun, Mar 01, 2020, 6:15 AM UTC

4d617832 wrote: post #29

cptskippy wrote: post #27

Earlier quoted context omitted.

> I deploy my RPi's in the field and don't put a monitor on them so I would expect ssh running as default. First time I found out about it was when reading the unit file... So I guess you weren't building those images? If you're building headless RPi images that's something you learn immediately.

I have a tendency to learn stuff in reverse. I used to make an SD Card ready, connected monitor and keyboard and enabled everything as needed. Then I got the task to deploy n-RPi's and looked at the image first to customize it for the requirements we had. That's when I looked around and saw the unusual unit file and tried to understand why the service would look at the boot partition to start a service. In the end I…

I don’t know the details of how they implement this but it sounds like you want a systemd drop in file to override the ConditionPathExists (or similar) directive (I’m assuming you can’t or don’t want to modify the upstream unit directly given the use of symlinks).

Re: 64 bit OS Raspberry Pi4 Benchmarks

#58

Post by yalok » Sun, Mar 01, 2020, 6:29 AM UTC

CivBase wrote: post #56

Noob question: What kind of optimizations are even responsible for those kinds of performance improvements? 32 bits is enough to utilize all 4 GB of the Raspberry Pi4, so I figured the only benefit of using a 64 bit OS would be to support 64 bit software. Why would a 64 bit build perform better than a 32 bit build on the same hardware?

64-bit ARM NEON (SIMD instruction set) is much more efficient vs 32-bit. And not just NEON, there are more registers as well, deeper pipeline, etc.

Re: 64 bit OS Raspberry Pi4 Benchmarks

#59

Post by bjoli » Sun, Mar 01, 2020, 6:36 AM UTC

lasermike026 wrote: post #14

Add a heatsink and fan. You'll get better performance.

I just put a copper and aluminium thing with large mass (about 100g) directly on the processor. Under light load it is about 20 over ambient. Despite CPU stress tests, I have never had it throttle.

Make sure it touches the usb chip.

Edit: my rock pi has a proper heat sink and it runs even cooler. 12 over ambient

Re: 64 bit OS Raspberry Pi4 Benchmarks

#60

Post by DCKing » Sun, Mar 01, 2020, 8:07 AM UTC

The CPU of the Raspberry Pi 4 is the only 64-bit ARM chip I've ever seen that doesn't include native AES instructions. As a result, it's much lower performance for network or disk encryption use cases.

Up until the RPi 4 I thought AES instructions were a part of AArch64, but I was wrong. Such a weird omission to make on (I expect) Broadcom's side. All other 64-bit ARM SBCs just have it, even the low cost ones.