Date: Fri, 21 Jun 2019 07:17:44 +0000 From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 238733] kvm disk i/o extremely slow Message-ID: <bug-238733-227@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D238733 Bug ID: 238733 Summary: kvm disk i/o extremely slow Product: Base System Version: 12.0-RELEASE Hardware: Any OS: Any Status: New Severity: Affects Only Me Priority: --- Component: kern Assignee: bugs@FreeBSD.org Reporter: rainer@ultra-secure.de Hi, I've posted this on the forum: https://forums.freebsd.org/threads/is-kvm-virtio-really-that-slow-on-freebs= d.71186/#post-430366 But I'll reiterate here. Basically, I'm running a FreeBSD 12 image created alongside this document: https://docs.openstack.org/image-guide/freebsd-image.html (plus swap) On a KVM host that is, TTBOMK, Ubuntu 18. Storage is Ceph Blockstorage, usi= ng pure NVMe SSDs - but I/O is capped at 2000 IOP/s. Using CentOS as a KVM guest, I basically get this: [root@centos ~]# dc3dd wipe=3D/dev/sdb dc3dd 7.1.614 started at 2019-06-20 07:54:22 +0000 compiled options: command line: dc3dd wipe=3D/dev/sdb device size: 83886080 sectors (probed) sector size: 512 bytes (probed) 42949672960 bytes (40 G) copied (100%), 342.37 s, 120 M/s=20=20=20=20=20=20= =20=20=20=20=20=20=20=20=20=20=20=20=20=20=20 input results for pattern `00': 83886080 sectors in output results for device `/dev/sdb': 83886080 sectors out dc3dd completed at 2019-06-20 08:00:05 +0000 Using FreeBSD, I get this: root@freebsd:~ # dc3dd wipe=3D/dev/vtbd2 dc3dd 7.2.646 started at 2019-06-20 09:37:10 +0200 compiled options: command line: dc3dd wipe=3D/dev/vtbd2 device size: 83886080 sectors (probed), 42,949,672,960 bytes sector size: 512 bytes (probed) 42949672960 bytes ( 40 G ) copied ( 100% ), 4585 s, 8.9 M/s=20=20=20=20=20= =20=20=20=20=20=20=20=20=20=20=20=20=20 input results for pattern `00': 83886080 sectors in output results for device `/dev/vtbd2': 83886080 sectors out dc3dd completed at 2019-06-20 10:53:35 +0200 The forum posting has fio-runs with the actual I/O numbers. Are the drivers really that bad? If this is the situation, FreeBSD is completely useless in the cloud. At le= ast for us. --=20 You are receiving this mail because: You are the assignee for the bug.=
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