From kvm Wed Dec 03 19:11:45 2008 From: "Adrian Schmitz" Date: Wed, 03 Dec 2008 19:11:45 +0000 To: kvm Subject: Virtio network performance problem Message-Id: <3D753CDC7D3A054CADC4DC2DF4C9F66502027873 () LGC-MX01 ! corp ! lehighgas ! local> X-MARC-Message: https://marc.info/?l=kvm&m=122833151603713 I'm having a problem with virtio networking. I mentioned this in a previous thread, but I'm starting a new one since Dor solved the problem I reported in the original thread. This appears to be a new problem. Iperf shows throughput of ~120 Mb/s between a Windows Server 2003 x64 guest and the br0 interface on the host. Also, a ping between the same two interfaces looks pretty bad: Pinging 10.10.10.128 with 32 bytes of data: Reply from 10.10.10.128: bytes=32 time=-389ms TTL=64 Reply from 10.10.10.128: bytes=32 time<1ms TTL=64 Reply from 10.10.10.128: bytes=32 time=392ms TTL=64 Reply from 10.10.10.128: bytes=32 time=392ms TTL=64 Reply from 10.10.10.128: bytes=32 time=377ms TTL=64 Reply from 10.10.10.128: bytes=32 time=392ms TTL=64 Reply from 10.10.10.128: bytes=32 time<1ms TTL=64 Reply from 10.10.10.128: bytes=32 time=401ms TTL=64 Reply from 10.10.10.128: bytes=32 time=1ms TTL=64 Using e1000 driver on this guest, iperf shows 320+ Mb/s throughput, and latency looks like it should. Host kernel: 2.6.18 KVM Version: 79 (modules and tools built and installed from source) Guest OS: Win2k3 x64 with all service packs and patches Guest virtio drivers: Version 3 (received from Dor Laor yesterday.. these fixed the guest OS crashes I was having with version 2) Any suggestions are greatly appreciated. If there's additional info I can provide, please let me know. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html