On 2007-10-25T13:11:56, Dejan Muhamedagic <[EMAIL PROTECTED]> wrote: > > The network is fully virtual, so I can't be hitting that limit. > Probably your xen is better than mine. Here I have a transfer > rate (guest to host) at times around 10mbit.
Paravirtualized is quite fast. I also don't connect my Xen network to the external NIC (which is the default), but use a decoupled internal bridged network, which is quite a bit faster, and also doesn't flood my LAN ;-) I couldn't figure it out myself, but it is described easily here: http://en.opensuse.org/Xen3_and_a_Virtual_Network With scp (and that includes encryption) I get ~35 MB/s between the DomU and Dom0. Certainly plenty for logging. > > As a data point: I was experiencing the very same drop message rate and > > doubled the buffers on syslog-ng and logd then; no change. > > > > Any suggestions? > > Remember this one: > http://lists.linux-ha.org/pipermail/linux-ha-dev/2007-April/014378.html I remember this, but I'm not quite sure I see how this relates to a performance issue. I eventually noticed that all those lost messages were not harmful (ie, CTS wasn't missing any of the patterns it was looking for), but that I was getting a _lot_ of noise from heartbeat's messaging core / flow-control during the message spikes. http://hg.linux-ha.org/dev/rev/69f0395c2ead seems to fix some of this for me. Now I do get lost packets on the wire, but heartbeat retransmits nicely, so nothing actually seems to go wrong ... Probably this means that MAXMISSING and FLOWCONTROL_LIMIT might require tuning. It'd be so much nicer if the messaging core was slightly more adaptive, but as we're moving towards openAIS, I'm not sure whether that's worth investigating in too much detail. Regards, Lars -- Teamlead Kernel, SuSE Labs, Research and Development SUSE LINUX Products GmbH, GF: Markus Rex, HRB 16746 (AG Nürnberg) "Experience is the name everyone gives to their mistakes." -- Oscar Wilde _______________________________________________________ Linux-HA-Dev: [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha-dev Home Page: http://linux-ha.org/
