Hi Efraim,

can you help me getting the support for transparent huge page on aarch64
for jemalloc into Guix?

https://lists.gnu.org/archive/html/guix-patches/2023-02/msg00698.html

I'm using those patches locally and have tested it so far by:

- Compiling the whole Rust toolchain

- Using this Rust toolchain to compile Icecat and a Rust Linux kernel
  module for thr GPU

I haven't noticed any issues so far.

Thanks, Roman.

Efraim Flashner <efraim@flashner.co.il> writes:

> [[PGP Signed Part:Undecided]]
> On Mon, Feb 20, 2023 at 11:31:04AM +0100, Roman Scherer wrote:
>>
>> Efraim Flashner <efraim@flashner.co.il> writes:
>> >
>> > I have two patches on the core-updates branch that should allow building
>> > openbios-qemu-ppc from aarch64. I'll try cherry-picking them to master
>> > and see if that allows building qemu-minimal.
>>
>> Hi Efraim,
>>
>> that would be great. I'm looking forward to try them out.
>
> I ran out of space while building qemu so I'm waiting on the build farm¹
> to see if qemu worked. Since qemu-minimal worked I pushed it upstream
> and current master should have that building now. I haven't tested
> building an image yet though.
>
> ¹ https://ci.guix.gnu.org/eval/211772
>
>> Since we are already talking about arm64 here, do you have experience
>> with transparent huge pages on aarch64?
>>
>> I would love to get some feedback on this one:
>>
>> https://lists.gnu.org/archive/html/guix-patches/2023-02/msg00698.html
>>
>> Do you know if any of the aarch64 build machines configured with a page
>> size > 4K? If so, I think that patch could help building more packages
>> on that architecture.
>>
>> Thanks, Roman.
>
> I'm pretty sure they all use a 4K page size. From
> gnu/packages/aux-files/linux-libre/6.1-arm64.conf:
> CONFIG_ARM64_4K_PAGES=y
> # CONFIG_ARM64_16K_PAGES is not set
> # CONFIG_ARM64_64K_PAGES is not set
>
> It looks like they're set for 4K pages. I'm not sure if it can be set
> for more than one size at once. As for the transparent huge pages, I'm
> pretty sure back in 2017 when I disabled it in jemalloc it was fairly
> broken on aarch64 but I don't see a reason to not enable it now.