Re: Poor network performance with Xen + OpenVPN?
I've not tried running OpenVPN against itself in a test bed. I no longer have the option as I had my provider downgrade my problematic VM from 4.4 to 3.4, which made the problem disappear. The OpenVPN config's I use are pretty standard. Server: port XXYYZ dev tun ca CA cert CERT key KEY dh DH server A.B.C.D 255.255.255.0 ifconfig-pool-persist ipp.txt keepalive 2 8 comp-lzo user nobody group nobody persist-key persist-tun status openvpn-status.log verb 3 push dhcp-option DNS 8.8.8.8 push dhcp-option DNS 8.8.4.4 Client: client dev tun proto udp remote A XXYYZ remote B XXYYZ resolv-retry infinite nobind user nobody group nobody persist-key persist-tun ca CA cert CERT key KEY ns-cert-type server verb 3 ping 2 ping-restart 5 On Sat, Aug 1, 2015 at 12:45 PM, Egoitz Aurrekoetxea ego...@sarenet.es wrote: Could you paste your onpenvpn’s server and client config files?. Which OS the client runs? Have you tested this openvpn connectivity without any network devices between them?. With for example an ip in the loopback interface of the openvpn server? Best regards, [image: sarenet] *Egoitz Aurrekoetxea* Departamento de sistemas 944 209 470 Parque Tecnológico. Edificio 103 48170 Zamudio (Bizkaia) ego...@sarenet.es www.sarenet.es Antes de imprimir este correo electrónico piense si es necesario hacerlo. El 30/7/2015, a las 11:41, seanr...@gmail.com escribió: I have the same issue. I managed to track it down to a difference between somewhere between Xen 3.4 and 4.4 (my provider uses both). 3.4 works fine (I can sustain a few mbps through OpenVPN). 4.4 I get ~0.05mbps max. I wasn't able to track it down. Both with the virtual drivers (if_xn) with all combinations of tso, lro, rxcsum and txcsum on/off tested. Sean On Wed, Jul 29, 2015 at 2:58 PM, Karl Pielorz kpielorz_...@tdx.co.uk wrote: --On 29 July 2015 14:28 +0200 Egoitz Aurrekoetxea ego...@sarenet.es wrote: Hi! Have you disabled tso, lro and friends?. If by that you mean, ifconfig xn0 -rxcsum -txcsum -tso4 -lro Yes - I've tried that on the virtual host running OpenVPN, it didn't seem to make any difference :( I'll hopefully get some more time later to look at it again. Regards, -Karl ___ freebsd-xen@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-xen To unsubscribe, send any mail to freebsd-xen-unsubscr...@freebsd.org ___ freebsd-xen@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-xen To unsubscribe, send any mail to freebsd-xen-unsubscr...@freebsd.org
Re: Poor network performance with Xen + OpenVPN?
I have the same issue. I managed to track it down to a difference between somewhere between Xen 3.4 and 4.4 (my provider uses both). 3.4 works fine (I can sustain a few mbps through OpenVPN). 4.4 I get ~0.05mbps max. I wasn't able to track it down. Both with the virtual drivers (if_xn) with all combinations of tso, lro, rxcsum and txcsum on/off tested. Sean On Wed, Jul 29, 2015 at 2:58 PM, Karl Pielorz kpielorz_...@tdx.co.uk wrote: --On 29 July 2015 14:28 +0200 Egoitz Aurrekoetxea ego...@sarenet.es wrote: Hi! Have you disabled tso, lro and friends?. If by that you mean, ifconfig xn0 -rxcsum -txcsum -tso4 -lro Yes - I've tried that on the virtual host running OpenVPN, it didn't seem to make any difference :( I'll hopefully get some more time later to look at it again. Regards, -Karl ___ freebsd-xen@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-xen To unsubscribe, send any mail to freebsd-xen-unsubscr...@freebsd.org ___ freebsd-xen@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-xen To unsubscribe, send any mail to freebsd-xen-unsubscr...@freebsd.org
Re: VM in Xen 4.1; poor packet forwarding performance on xn0
Hi Roger, This is what they provided me: - The Xen 4.x node is running a custom 3.1.1 kernel. - The Xen 3.x node is running a 2.6.18 kernel. They didn't elaborate on the customisations. :( Sean On Sat, Apr 26, 2014 at 1:06 PM, Roger Pau Monné roger@citrix.comwrote: On 26/04/14 13:57, seanr...@gmail.com wrote: Hi Roger, Thanks for the patch -- sadly, it didn't work. No change. Hello, I did have to modify a bit for releng/10.0; for some reason patch refused to apply it cleanly. It looked fairly straightforward but I attached inline the patch I ultimately applied below just in case I got it wrong. Patch looks fine. Are there any other potential differences between Xen 3.4 and 4.1? (my provider migrated my problem VPS to a 3.4 host and the problem evaporated; I am trying this on a new 4.1 VPS that I was able to reproduce the problem on). I'm quite sure this is not related to the underlying Xen version, but to the Linux Dom0 kernel version your provider is using, could you ask them the Linux versions they are using on the 4.1 and 3.4 hosts? Roger. ___ freebsd-xen@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-xen To unsubscribe, send any mail to freebsd-xen-unsubscr...@freebsd.org
Re: VM in Xen 4.1; poor packet forwarding performance on xn0
Hi Roger, Thanks for the patch -- sadly, it didn't work. No change. I did have to modify a bit for releng/10.0; for some reason patch refused to apply it cleanly. It looked fairly straightforward but I attached inline the patch I ultimately applied below just in case I got it wrong. Are there any other potential differences between Xen 3.4 and 4.1? (my provider migrated my problem VPS to a 3.4 host and the problem evaporated; I am trying this on a new 4.1 VPS that I was able to reproduce the problem on). Sean Index: hvm.c === --- hvm.c (revision 264963) +++ hvm.c (working copy) @@ -626,6 +626,7 @@ xhp.domid = DOMID_SELF; xhp.index = HVM_PARAM_CALLBACK_IRQ; +#if 0 if (xen_feature(XENFEAT_hvm_callback_vector) != 0) { int error; @@ -638,6 +639,7 @@ printf(Xen HVM callback vector registration failed (%d). Falling back to emulated device interrupt\n, error); } +#endif xen_vector_callback_enabled = 0; if (dev == NULL) { /* @@ -783,7 +785,7 @@ info.mfn = vtophys(vcpu_info) PAGE_SHIFT; info.offset = vtophys(vcpu_info) - trunc_page(vtophys(vcpu_info)); - rc = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, info); + rc = 1; if (rc != 0) DPCPU_SET(vcpu_info, HYPERVISOR_shared_info-vcpu_info[cpu]); else On Tue, Apr 22, 2014 at 3:10 PM, Roger Pau Monné roger@citrix.comwrote: On 18/04/14 16:57, seanr...@gmail.com wrote: Hi there freebsd-xen, I tried first on freebsd-questions@ without success, so I thought to retry here. I run OpenVPN on a FreeBSD 10.0-Rp1 VM in Xen 4.1 (HVM). I am experiencing slow network performance on xn0 that seems to have developed after I upgraded to FreeBSD 10 (no other changes). I can only achieve about 0.5mbps through this interface when forwarding packets; packets in a single direction are fine (e.g; downloading to the VPS or pushing from the VPS) and clock in at many (10 usually) mbps. Interestingly, my identical VM (configuration managed centrally) running on Xen 3.4 (HVM) does *not* have this issue. Hello, The difference between Xen 3.4 and Xen 4.1 is that FreeBSD will make use of the vector callback, the PV timer and PV IPIs when running on Xen 4.0 (which should provide better performance). I'm attaching a patch that will make FreeBSD behave the same way when running on either Xen 3.4 or Xen 4.1 (by disabling all this new additions), could you please give it a try? I did a little debugging and here's what I've noticed: - Not related to OpenVPN, repro'd using ssh -d. - Slow VM has a very low rate of context switches (~250) while forwarding, fast VM has a lot more (~2000) sampled over 5 seconds using systat -v. - I can't repro a context switch limit (tried a limited fork() bomb). - Tried with *and* without LRO and TSO on xn0 (and all combinations of LRO and TSO on/off) I've got the feeling that the issue you are seeing is not related to the Xen version itself, but the Linux Dom0 kernel version (which I suppose is different in the Xen 3.4 and Xen 4.1 hosts). Could you ask your provider which Linux Dom0 kernel are they using on the different hosts? Roger. ___ freebsd-xen@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-xen To unsubscribe, send any mail to freebsd-xen-unsubscr...@freebsd.org
Re: VM in Xen 4.1; poor packet forwarding performance on xn0
On Sat, Apr 19, 2014 at 1:11 PM, Tiago Ribeiro sha...@gmail.com wrote: Em 18/04/2014, às 11:57, seanr...@gmail.com seanr...@gmail.com escreveu: Hi there freebsd-xen, I tried first on freebsd-questions@ without success, so I thought to retry here. I run OpenVPN on a FreeBSD 10.0-Rp1 VM in Xen 4.1 (HVM). I am experiencing slow network performance on xn0 that seems to have developed after I upgraded to FreeBSD 10 (no other changes). I can only achieve about 0.5mbps through this interface when forwarding packets; packets in a single direction are fine (e.g; downloading to the VPS or pushing from the VPS) and clock in at many (10 usually) mbps. Interestingly, my identical VM (configuration managed centrally) running on Xen 3.4 (HVM) does *not* have this issue. I did a little debugging and here's what I've noticed: - Not related to OpenVPN, repro'd using ssh -d. - Slow VM has a very low rate of context switches (~250) while forwarding, fast VM has a lot more (~2000) sampled over 5 seconds using systat -v. - I can't repro a context switch limit (tried a limited fork() bomb). - Tried with *and* without LRO and TSO on xn0 (and all combinations of LRO and TSO on/off) I started digging into the Xen drivers but I realised I am not equipped to debug this. I'm looking for suggestions on what to check. My provider is offering to move me to an older Xen host but I'd like to see if I can help identify a bug either in my configuration or perhaps in FreeBSD's Xen code. Sean _ Do you use pf? I do. Fairly simple ruleset: default deny, a few specific port allows, NAT. Sean ___ freebsd-xen@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-xen To unsubscribe, send any mail to freebsd-xen-unsubscr...@freebsd.org
VM in Xen 4.1; poor packet forwarding performance on xn0
Hi there freebsd-xen, I tried first on freebsd-questions@ without success, so I thought to retry here. I run OpenVPN on a FreeBSD 10.0-Rp1 VM in Xen 4.1 (HVM). I am experiencing slow network performance on xn0 that seems to have developed after I upgraded to FreeBSD 10 (no other changes). I can only achieve about 0.5mbps through this interface when forwarding packets; packets in a single direction are fine (e.g; downloading to the VPS or pushing from the VPS) and clock in at many (10 usually) mbps. Interestingly, my identical VM (configuration managed centrally) running on Xen 3.4 (HVM) does *not* have this issue. I did a little debugging and here's what I've noticed: - Not related to OpenVPN, repro'd using ssh -d. - Slow VM has a very low rate of context switches (~250) while forwarding, fast VM has a lot more (~2000) sampled over 5 seconds using systat -v. - I can't repro a context switch limit (tried a limited fork() bomb). - Tried with *and* without LRO and TSO on xn0 (and all combinations of LRO and TSO on/off) I started digging into the Xen drivers but I realised I am not equipped to debug this. I'm looking for suggestions on what to check. My provider is offering to move me to an older Xen host but I'd like to see if I can help identify a bug either in my configuration or perhaps in FreeBSD's Xen code. Sean ___ freebsd-xen@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-xen To unsubscribe, send any mail to freebsd-xen-unsubscr...@freebsd.org