User avatar
rpdom
Posts: 15232
Joined: Sun May 06, 2012 5:17 am
Location: Chelmsford, Essex, UK

Re: Why moving to 64bit?

Sat Aug 24, 2019 4:44 pm

bullen wrote:
Sat Aug 24, 2019 4:36 pm
Ok, when is the 64-bit Raspbian coming out then?
Just in time for the Pi 5. :roll:

You've been around here long enough to know that release dates are never announced in advance.

jdonald
Posts: 413
Joined: Fri Nov 03, 2017 4:36 pm

Re: Why moving to 64bit?

Sat Aug 24, 2019 5:04 pm

bullen wrote:
Sat Aug 24, 2019 4:15 pm
Current Minecraft requires 64-bit OS.
False: https://www.raspberrypi.org/forums/view ... p?t=245947

* 1.14.3 runs on Raspian 32-bit. Still narrowing down a bug in 1.14.4 + LWJGL3.
Last edited by jdonald on Sat Aug 24, 2019 7:37 pm, edited 1 time in total.

W. H. Heydt
Posts: 10905
Joined: Fri Mar 09, 2012 7:36 pm
Location: Vallejo, CA (US)

Re: Why moving to 64bit?

Sat Aug 24, 2019 5:45 pm

rpdom wrote:
Sat Aug 24, 2019 4:44 pm
bullen wrote:
Sat Aug 24, 2019 4:36 pm
Ok, when is the 64-bit Raspbian coming out then?
Just in time for the Pi 5. :roll:

You've been around here long enough to know that release dates are never announced in advance.
That soon? I'd expect more around the time of the Pi6 or Pi7.

pica200
Posts: 138
Joined: Tue Aug 06, 2019 10:27 am

Re: Why moving to 64bit?

Sat Aug 24, 2019 8:09 pm

If you wanna use a 64 bit distro use one of the unofficial ones. Don't count on Raspian 64 bit any time soon.

I switched to one recently and got most issues solved now. Running pretty good and having the familar xfce de is a bonus. On a side note: Firefox is now beating Chromium from Raspian and runs pretty smooth. No comparison to FF ESR on Raspian.

ejolson
Posts: 3586
Joined: Tue Mar 18, 2014 11:47 am

Re: Why moving to 64bit?

Sun Aug 25, 2019 7:17 pm

pica200 wrote:
Sat Aug 24, 2019 8:09 pm
Don't count on Raspian 64 bit any time soon.
Like the Pi 4B, a 64-bit version of Raspbian may happen sooner than people think.

The reason is because it is more and more difficult as time goes on to get software developed for 64-bit to run correctly on 32-bit machines. For example, I just discovered the package btrfs-progs that is part of Raspbian Buster is unable to make filesystem snapshots because of a regression concerning statfs on 32-bit systems. More information is available here.

Note that since btrfs-progs worked fine on Raspbian Stretch, I expect this to be sorted fairly quickly.

pica200
Posts: 138
Joined: Tue Aug 06, 2019 10:27 am

Re: Why moving to 64bit?

Sun Aug 25, 2019 9:30 pm

Yeah, not saying it will never happen. There will be no choice as software eventually moves away from 32 bit but a few missing/broken packages is not reason enough yet (at least for RPiF/T). In my opinion it's totally worth it but there may still be bugs or you have to fiddle with settings to workaround driver bugs.

User avatar
AdamStanislav
Posts: 147
Joined: Sun Mar 10, 2019 2:44 am
Location: Wisconsin
Contact: YouTube

Re: Why moving to 64bit?

Sun Aug 25, 2019 10:24 pm

ejolson wrote:
Sun Aug 25, 2019 7:17 pm
Like the Pi 4B, a 64-bit version of Raspbian may happen sooner than people think.
As long as it can run both, the new 64-bit software and the old 32-bit software, it will be a step in the right direction.

Paul Hutch
Posts: 390
Joined: Fri Aug 25, 2017 2:58 pm
Location: Blackstone River Valley, MA, USA
Contact: Website

Re: Why moving to 64bit?

Mon Aug 26, 2019 1:20 pm

W. H. Heydt wrote:
Sat Aug 24, 2019 5:45 pm
rpdom wrote:
Sat Aug 24, 2019 4:44 pm
bullen wrote:
Sat Aug 24, 2019 4:36 pm
Ok, when is the 64-bit Raspbian coming out then?
Just in time for the Pi 5. :roll:

You've been around here long enough to know that release dates are never announced in advance.
That soon? I'd expect more around the time of the Pi6 or Pi7.

From 20 days ago at the beginning of this thread:
jamesh wrote:
Tue Aug 06, 2019 2:44 pm
I expect by Pi6 (and Pi5 TBH) that we will have an official 64bit OS.
...

W. H. Heydt
Posts: 10905
Joined: Fri Mar 09, 2012 7:36 pm
Location: Vallejo, CA (US)

Re: Why moving to 64bit?

Mon Aug 26, 2019 2:00 pm

Paul Hutch wrote:
Mon Aug 26, 2019 1:20 pm
W. H. Heydt wrote:
Sat Aug 24, 2019 5:45 pm
rpdom wrote:
Sat Aug 24, 2019 4:44 pm

Just in time for the Pi 5. :roll:

You've been around here long enough to know that release dates are never announced in advance.
That soon? I'd expect more around the time of the Pi6 or Pi7.

From 20 days ago at the beginning of this thread:
jamesh wrote:
Tue Aug 06, 2019 2:44 pm
I expect by Pi6 (and Pi5 TBH) that we will have an official 64bit OS.
...
The first 90% of effort on a software project takes the first 90% of the time. The remaining 10% of the effort takes the remaining 90% of the time.

ejolson
Posts: 3586
Joined: Tue Mar 18, 2014 11:47 am

Re: Why moving to 64bit?

Mon Aug 26, 2019 2:19 pm

W. H. Heydt wrote:
Mon Aug 26, 2019 2:00 pm
The first 90% of effort on a software project takes the first 90% of the time. The remaining 10% of the effort takes the remaining 90% of the time.
The problem with the last 10% taking a disproportionate amount of energy was solved recently by what is called agile methodology: Simply put the code in production when the project 90% finished.

Here is a list of reasons people have mentioned that favour 64-bit:
  • General speed improvements resulting from twice the registers.
  • Specific speed improvements resulting from the availability of fast 64-bit integer arithmetic.
  • Memory management techniques based on having a virtual address space much larger than physical space that benefit the kernel, databases, parallel processing and garbage collectors.
  • Additional security resulting from 64-bit address space layout randomization.
  • More 32-bit regressions are introduced in open source software as a result of development targeting 64-bit architectures.
  • Some software is 64-bit only.
Did I miss anything?

jerrm
Posts: 194
Joined: Wed May 02, 2018 7:35 pm

Re: Why moving to 64bit?

Mon Aug 26, 2019 2:38 pm

ejolson wrote:
Mon Aug 26, 2019 2:19 pm
The problem with the last 10% taking a disproportionate amount of energy was solved recently by what is called agile methodology: Simply put the code in production when the project 90% finished.
Recently?

I've been using agile techniques for 30 years - just without the buzzwords and theology. Agile has some value in standardizing some prinicples between shops, but the core principles are nothing new.
Last edited by jerrm on Mon Aug 26, 2019 3:22 pm, edited 3 times in total.

drgeoff
Posts: 9819
Joined: Wed Jan 25, 2012 6:39 pm

Re: Why moving to 64bit?

Mon Aug 26, 2019 2:57 pm

ejolson wrote:
Mon Aug 26, 2019 2:19 pm
....recently by what is called agile methodology: Simply put the code in production when the project 90% finished.
Some people, especially those with a hardware background, would query what is recent about software development doing that. Here's looking at you MS. :) Obligatory disclaimer: Other software producers are available.

hippy
Posts: 5970
Joined: Fri Sep 09, 2011 10:34 pm
Location: UK

Re: Why moving to 64bit?

Mon Aug 26, 2019 5:46 pm

drgeoff wrote:
Mon Aug 26, 2019 2:57 pm
Obligatory disclaimer: Other software producers are available.
I was rather surprised when Raspbian Buster was released ahead of Debian officially releasing Buster. Of course that was more than 90% complete at the time.

As you say there's nothing uncommon in releasing something which isn't in the form it will finally be in. That's exactly what has been done for the Pi 4B and for entirely good reasons. It is often better to release what there is and let people use that than make everyone wait until everything is ready for release.

User avatar
Gavinmc42
Posts: 3753
Joined: Wed Aug 28, 2013 3:31 am

Re: Why moving to 64bit?

Tue Aug 27, 2019 2:59 am

Here is a list of reasons people have mentioned that favour 64-bit:
General speed improvements resulting from twice the registers.
Specific speed improvements resulting from the availability of fast 64-bit integer arithmetic.
Memory management techniques based on having a virtual address space much larger than physical space that benefit the kernel, databases, parallel processing and garbage collectors.
Additional security resulting from 64-bit address space layout randomization.
More 32-bit regressions are introduced in open source software as a result of development targeting 64-bit architectures.
Some software is 64-bit only.
Did I miss anything?
Gentoo64 is A72 optimised, for a ?% improvement over A53.
Not sure much difference that makes.

So even a 64bit OS might not be an optimised 64bit OS :D
How much further performance can be got from tweaks.
1GB, 2GB, 4GB, how to slice up that memory for best performance?
I'm dancing on Rainbows.
Raspberries are not Apples or Oranges

pica200
Posts: 138
Joined: Tue Aug 06, 2019 10:27 am

Re: Why moving to 64bit?

Tue Aug 27, 2019 5:57 am

Has this been observed anywhere else yet? Enabling window compositing seems to slow graphics down by a lot. Especially noticeable through high rendering lag. I think Raspian suffers from the same problem but since lxde takes basically nothing it's not so noticeable. But on xfce on a full 64 bit OS it's very noticeable (yes, GPU driver is working and loaded as Xorg.0.log reveals (glamoregl with V3D)). Driver bug?

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 23708
Joined: Sat Jul 30, 2011 7:41 pm

Re: Why moving to 64bit?

Tue Aug 27, 2019 8:52 am

I presume that all the people talking about wanting 64bit OS are keeping a close eye on our Linux repo? Always lots of 64 bit stuff going on in there, mostly from third parties. Worthwhile doing to keep abreast of what is actually going on rather than reading random forum posts.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed. Here's an example...
"My grief counseller just died, luckily, he was so good, I didn't care."

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 23708
Joined: Sat Jul 30, 2011 7:41 pm

Re: Why moving to 64bit?

Tue Aug 27, 2019 8:53 am

pica200 wrote:
Tue Aug 27, 2019 5:57 am
Has this been observed anywhere else yet? Enabling window compositing seems to slow graphics down by a lot. Especially noticeable through high rendering lag. I think Raspian suffers from the same problem but since lxde takes basically nothing it's not so noticeable. But on xfce on a full 64 bit OS it's very noticeable (yes, GPU driver is working and loaded as Xorg.0.log reveals (glamoregl with V3D)). Driver bug?
We did find some odd results with window compositing prior to Pi4 release, cannot remember if we ever determined the bottleneck.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed. Here's an example...
"My grief counseller just died, luckily, he was so good, I didn't care."

pica200
Posts: 138
Joined: Tue Aug 06, 2019 10:27 am

Re: Why moving to 64bit?

Tue Aug 27, 2019 1:43 pm

jamesh wrote:
Tue Aug 27, 2019 8:52 am
I presume that all the people talking about wanting 64bit OS are keeping a close eye on our Linux repo.
I do keep an eye on changes to the Linux fork.
jamesh wrote:
Tue Aug 27, 2019 8:53 am
We did find some odd results with window compositing prior to Pi4 release, cannot remember if we ever determined the bottleneck.
So it is a driver bug i guess. Another thing i found is high audio latency through HDMI fixed by tsched=0. After i saw that i did some research and found on the Arch Wiki it's a known problem with a few drivers. Something new i found is enabling non-power of 2 textures in snes9x-gtk and going into fullscreen heavily corrupts graphics creating flickering artifacts all over the place. This may or may not be a driver bug aswell not sure (some GPUs want this alignment as far as i know).

jdonald
Posts: 413
Joined: Fri Nov 03, 2017 4:36 pm

Re: Why moving to 64bit?

Tue Aug 27, 2019 2:12 pm

ejolson wrote:
Mon Aug 26, 2019 2:19 pm
Here is a list of reasons people have mentioned that favour 64-bit:
...
Did I miss anything?
Here are two that became apparent in this thread, despite not arising in the earlier 64-bit mega-topics:
  • 32-bit conflates all the performance losses from multiple flavors of 32-bit (ARMv6, ARMv7-compatible, ARMv7 tuned for Cortex-A7~72). Even if a 2x performance improvement for VPN, 10x on sysbench, and web browsers without NEON are not due to 64-bit per se, it's not practical for distro maintainers let alone users to work around this. Providing 64-bit packages avoids having to reason about performance left on the table from NEON, integer division, IFTTT instructions, and other 32-bit extensions.
  • Falls under the "some software only 64-bit", but bringing up Dolphin raised the issue of dynamic recompilation. It is far more work to implement and maintain a JIT for multiple target architectures, hence Dolphin fully dropped support for armhf and 32-bit x86.

jdonald
Posts: 413
Joined: Fri Nov 03, 2017 4:36 pm

Re: Why moving to 64bit?

Thu Aug 29, 2019 4:44 pm

pica200 wrote:
Tue Aug 27, 2019 1:43 pm
Something new i found is enabling non-power of 2 textures in snes9x-gtk and going into fullscreen heavily corrupts graphics creating flickering artifacts all over the place. This may or may not be a driver bug aswell not sure (some GPUs want this alignment as far as i know).
Mesa v3d exposes GL_ARB_texture_non_power_of_two and GL_OES_texture_npot. If the hardware doesn't inherently support npot it should fall back to software for compliance, running slowly but not with artifacts. However, this doesn't rule out a bug in snes9x-gtk, or Xorg etc.

Does this not happen on 32-bit?

I suspect that rendering problems on Manjaro are largely specific to that distro, not 64-bit per se. I've still been unable to run Dolphin there being unable to create a GLES context, but things work on Gentoo and Raspbian 64-bit.

pica200
Posts: 138
Joined: Tue Aug 06, 2019 10:27 am

Re: Why moving to 64bit?

Thu Aug 29, 2019 5:49 pm

jdonald wrote:
Thu Aug 29, 2019 4:44 pm
Does this not happen on 32-bit?
Yeah, only happening with 16 bit textures. Changing to 32 bit textures fixes it but makes flickering effekts appear as solid color.
jdonald wrote:
Thu Aug 29, 2019 4:44 pm
I suspect that rendering problems on Manjaro are largely specific to that distro, not 64-bit per se. I've still been unable to run Dolphin there being unable to create a GLES context, but things work on Gentoo and Raspbian 64-bit.
It uses the exact same kernel Raspian and Gentoo use from the RPi fork on GitHub. The only difference really is in the userland software which is pretty bleeding edge but not as much as Arch. GPU support is not even official yet you can enable it renaming the 99-fbturbo.conf and to fix the compositing slowdown you have to disable that in the window tweaks settings. After that it's working fine for the most part. When i tried higan and switched it to the OpenGL renderer it gives errors on program start about being unable to init OpenGL. But on the other hand stuff like browsers seem to be happy with OpenGL.

jdonald
Posts: 413
Joined: Fri Nov 03, 2017 4:36 pm

Re: Why moving to 64bit?

Thu Aug 29, 2019 11:05 pm

Okay I can run Dolphin with GLES3 on Manjaro now. I thought it was a problem with Mesa or libdrm, but just turns out I had unintentionally built off an older commit.
pica200 wrote:
Thu Aug 29, 2019 5:49 pm
tried higan and switched it to the OpenGL renderer it gives errors on program start about being unable to init OpenGL.
Just tested and I see the same issue on Raspbian 32-bit. Persists with LIBGL_SOFTWARE_ALWAYS=1 so I suspect it's more likely a higan bug than a driver problem.
pica200 wrote:
jdonald wrote:
Thu Aug 29, 2019 4:44 pm
[snes9x-gtk npot] Does this not happen on 32-bit?
Yeah, only happening with 16 bit textures.
I mean does this not happen with a 32-bit kernel + Mesa (e.g Raspbian)? Due to the title and context of this thread you implied that the npot bug is 64-bit-specific.

pica200
Posts: 138
Joined: Tue Aug 06, 2019 10:27 am

Re: Why moving to 64bit?

Thu Aug 29, 2019 11:38 pm

jdonald wrote:
Thu Aug 29, 2019 11:05 pm
Okay I can run Dolphin with GLES3 on Manjaro now. I thought it was a problem with Mesa or libdrm, but just turns out I had unintentionally built off an older commit.
Good to hear. Would have been strange if that distro behaved much differently than the others. I have not tried Dolphin yet and not sure if it's worth it considering the poor performance right now. I still would like to see a real VC6 driver with Vulkan support. That would make a real difference imho.
jdonald wrote:
Thu Aug 29, 2019 11:05 pm
Just tested and I see the same issue on Raspbian 32-bit. Persists with LIBGL_SOFTWARE_ALWAYS=1 so I suspect it's more likely a higan bug than a driver problem.
Yeah, did not say it's a driver bug. Everything else is happy with it as said. Probably should report this to byuu.
jdonald wrote:
Thu Aug 29, 2019 11:05 pm
I mean does this not happen with a 32-bit kernel + Mesa (e.g Raspbian)? Due to the title and context of this thread you implied that the npot bug is 64-bit-specific.
Misunderstood. I have not tried this on Raspian but may do that later (need to search for another unused microSD). It's very likely not 64 bits specific.

User avatar
CypherOz
Posts: 45
Joined: Fri Jul 05, 2019 1:46 pm

Re: Why moving to 64bit?

Fri Aug 30, 2019 12:39 am

Besides the obvious address space, 64bit chips also (usually) have the following benefits:
  • Wider data paths and bigger better caches
  • More registers thus faster running programs
  • Better special instructions (SSE MMX etc.)
RPi5C+ (wishing) will have at least 16GB support and 64bit Raspian
--
Regards, Kym
Retired software bloke from Adelaide, South Australia

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 23708
Joined: Sat Jul 30, 2011 7:41 pm

Re: Why moving to 64bit?

Fri Aug 30, 2019 8:55 am

CypherOz wrote:
Fri Aug 30, 2019 12:39 am
Besides the obvious address space, 64bit chips also (usually) have the following benefits:
  • Wider data paths and bigger better caches
  • More registers thus faster running programs
  • Better special instructions (SSE MMX etc.)
RPi5C+ (wishing) will have at least 16GB support and 64bit Raspian
Pi4 can technically address 16GB, and I would think a decent 64bit Raspbian will eventually become available for it. No need to wait for the Pi5.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed. Here's an example...
"My grief counseller just died, luckily, he was so good, I didn't care."

Return to “General discussion”