On Dec 1, 2010, at 11:37 AM, Steven Dake wrote: > On 11/30/2010 12:02 PM, Wez Furlong wrote: >> Hey folks, >> >> We use the agreed messaging mode of spread for coordinating nodes in our >> cluster, and I've just discovered corosync. We have a love-hate >> relationship with the spread software, and the possibility of moving to >> another system with similar facilities is appealing to us (but at the same >> time, we're not going to blindly leap!) >> > > Which parts of spread don't you like? The main problem we had with > spread was the license which made it unsuitable for use in open source > distributions.
The license is a source of frustration for us as well. We've had occasional mysterious hangs in the spread libraries (blocking with no timeout) that are frustrating, but they are rare enough to not have posed a serious problem for us (we have watchdog facilities for this)--it would be nice to eliminate them, and/or to be able to work with an open community to eliminate them. >> The evs_overview(8) docs suggest that EVS is not currently ready for prime >> time, so I'm wondering which aspects of it need work? >> > > Documentation in corosync is pretty weak and out of date. We spent our > time writing good code instead ;) We hope to address the documentation > issues in the future now that the code is quite stable. I know how that goes :-) > EVS is primetime - the api is very simple. We do recommend people use > the CPG api (man cpg_overview) because it is where we intend to do our > future development. I've very quickly skimmed the cpg man pages; the API looks very similar to the evs functions; what's the main difference between the cpg and evs facilities? > Corosync supports native rdma, udp broadcast, udp multicast, and udp > unicast transports. Unlike spread, corosync is designed to only work > within a LAN and as a result, there is higher latency when using over > long haul networks. Do you have any numbers (rough/ballpark will be fine) on that increased latency? Are there any plans to improve operation over a wider area network, or is that a definite non-goal for corosync? Thanks! --Wez. _______________________________________________ Openais mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/openais
