After upgrading to qemu-2.11.0, I see a noticeable delay in qemu-arm when starting any application. I use qemu-arm in a chroot (via binfmt wrapper) to build packages, so when running an emerge which spawns many sub-processes it really slows down emulation. If I downgrade back to qemu-2.10.1-r1 in an overlay, the problem goes away. I also tried upgrading to the freshly added 2.11.1 but it has the same problem as 2.11.0. qemu-aarch64 does not exhibit this behaviour using it in the same fashion (qemu+binfmt_wrapper+chroot) Reproducible: Always
I can confirm this problem. With the update to 2.11 compiling packages for a raspberry pie using qemu-arm and a chroot has become impossible. It takes ages for ever single operation :-(.
It looks as though the patches mentioned in the linked bug report have made their way into upstream, hopefully meaning qemu-2.12.
(In reply to David Flogeras from comment #2) > It looks as though the patches mentioned in the linked bug report have made > their way into upstream, hopefully meaning qemu-2.12. I don't see any of the patches in the qemu git repository. Otherwise, I would have created a small patchset applying these patches already onto the 2.11.1 version we currently have in tree. Can you point me to the commits, please?
Hmm, it looks like I may be wrong. Here's the commits I saw https://git.qemu.org/?p=qemu.git;a=search;s=Luke+Shumaker;st=author It seems 9/10 of his commits were pulled, but the one missing is the one he mentioned in the pull-request as being the actual fix. Not sure why.
It looks as though the final patch was accepted/applied https://git.qemu.org/?p=qemu.git;a=commit;h=2a53535af471f4bee9d6cb5b363746b8d5ed21dd (Also see the linked bug) So it appears it will make it into 2.12.0 According to the discussion on launchpad, the patchset applies cleanly to 2.11 (but it also look as though 2.12.0 is imminent and might be a waste of effort to backport).
For fun, I applied just the commit I linked in comment #4 to qemu 2.11.1-r1 in tree, and the slowdown issue went away for me.
(In reply to David Flogeras from comment #5) > https://git.qemu.org/?p=qemu.git;a=commit; > h=2a53535af471f4bee9d6cb5b363746b8d5ed21dd Confirming that this patch fixes the slowdown issue.
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=e564224a7c1a74c8772284a7b40c39f35ae9250f commit e564224a7c1a74c8772284a7b40c39f35ae9250f Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2018-04-04 15:49:32 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2018-04-04 15:52:12 +0000 app-emulation/qemu: ebuild maintenance * desnappify * fix ARM performance issue. Thanks to David Flogeras and Alexander Tsoy. Closes: https://bugs.gentoo.org/647952 Closes: https://bugs.gentoo.org/651602 Package-Manager: Portage-2.3.28, Repoman-2.3.9 app-emulation/qemu/Manifest | 1 + .../qemu/{qemu-2.11.1-r52.ebuild => qemu-2.11.1-r53.ebuild} | 6 +++--- 2 files changed, 4 insertions(+), 3 deletions(-)
