Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 17 Sep 2018 04:46:57 +1000
From:      Peter Jeremy <peter@rulingia.com>
To:        freebsd-arm@freebsd.org
Subject:   Poor virtio performance on Scaleway ARM systems
Message-ID:  <20180916184657.GB24416@server.rulingia.com>

next in thread | raw e-mail | index | archive | help

--VS++wcV0S1rZb1Fb
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

I have been playing with the 4-core ARM64 VPSs on https://www.scaleway.com
and notice that the disk I/O performance (using virtio_blk) is abyssmal.
Using "dd if=3D/dev/{vda|vtbd0} of=3D/dev/null bs=3D256k count=3D4096", I g=
et
400-500MBps, whilst under FreeBSD-12, I get about 5MBps.  I've checked on a
couple of instances and both Linux & FreeBSD on the same instance and get
similar results.  Linux & FreeBSD are both using a virtio block device
attached to the PCI bus.  Rebuilding FreeBSD to turn off all the debugging
has no effect.

The only oddity I've found is that FreeBSD is reporting very high interrupt
rates on gic0,p11, gic0,s4 and gic0,s5 whilst disk I/O is occurring.
Unfortunately, I can't tell what is attached to those interrupts (it's
not obvious from the dmesg and reported as "+").

I've done some searching and have only found general FUD ("FreeBSD virtio
isn't any good") and nothing specifically related to Scaleway.

Can anyone suggest where to look for a solution?

--=20
Peter Jeremy

--VS++wcV0S1rZb1Fb
Content-Type: application/pgp-signature; name="signature.asc"

-----BEGIN PGP SIGNATURE-----
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=M/U+
-----END PGP SIGNATURE-----

--VS++wcV0S1rZb1Fb--



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20180916184657.GB24416>