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0 pointssirn5y ago0 comments

Was your emulation done with qemu user space emulator[1] (the syscall translation layer) or qemu system emulator[2] (the VM)? If it was qemu-system you might have better numbers with qemu-user-static, which does binary translation similar to Rosetta 2 rather than a being a full system emulator with all its overhead.

You can probably use qemu-user-static to translate x86-64-only binaries in a Linux container on an ARM machine, too, but I have never tried.

[1]: https://www.qemu.org/docs/master/user/main.html

[2]: https://www.qemu.org/docs/master/system/index.html

0 comments

bmalehorn5y ago

I ran this on a Linux laptop - it looks like it's running qemu-user-static:

    root        9934  103  0.0 125444  6664 pts/0    Rl+  12:25   0:12 /usr/bin/qemu-aarch64-static /usr/bin/gzip

So it might be that Docker already runs a native x86_64 Linux, then uses qemu-static binary translation.

sirnOP5y ago

That's strange, in my experience it shouldn't have 6x slowdown. Probably might be due to several factors, but here's your test, running on my system without Docker:

Ryzen 3900X (host machine)

    $ dd if=/dev/urandom bs=4k count=10k | gzip >/dev/null
    10240+0 records in
    10240+0 records out
    41943040 bytes (42 MB, 40 MiB) copied, 1.02284 s, 41.0 MB/s

qemu-aarch64-static

    $ dd if=/dev/urandom bs=4k count=10k | proot -R /tmp/aarch64-alpine -q qemu-aarch64-static sh -c 'gzip >/dev/null'
    10240+0 records in
    10240+0 records out
    41943040 bytes (42 MB, 40 MiB) copied, 3.33964 s, 12.6 MB/s

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