Each node doesn't have an entry for every other node... only the server, which is doing NAT by default. So this isn't going to ever affect MPI or node to node performance at all. As for the server, it's probably not a big enough problem to justify the complication yet... the entries you pasted look to me like they must be from a server.
Jeremy
At 12:52 PM 1/22/2003 -0500, Jeff Squyres wrote:
On Wed, 22 Jan 2003, Jeremy Enos wrote: > I hadn't thought of this before... is there any data on the overhead of > iptables rules? i.e. 20 rules vs 200 rules vs 2000 rules? If it's > insignificant, I would think it would be best to keep them individuallyI agree. But I'd be willing to bet that there's a performance penalty. I don't have any numbers; does anyone have some time to generate some, or poke through the iptables code to see what it does? Disclaimer: I've never looked at the iptables code to know how it works. I'd be willing to bet that there's linked lists (or arrays) of rules that are traversed for each packet (or connection setup). So, the more rules you have, the more time is spent processing each item. That being said, it all depends on how iptables indexes its rules -- there could be intelligent lookups such that only relevant rules are examined/invoked for each packet/connection (vs. searching through all the rules to find the relevant ones). [shrug] > assigned as they are now. I say that because once we "group" nodes into > a mask, there are going to be feature requests for exceptions, > priorities, overlaps, etc. Eewww. Ick. Running away now. I agree -- getting in the feeping creatures would not be a good idea. But if we provide reasonable defaults that cover 70-80% of common configurations, the remaining 20-30% can go hand-tweak files if they want/need to. -- {+} Jeff Squyres {+} [EMAIL PROTECTED] {+} http://www.lam-mpi.org/ ------------------------------------------------------- This SF.net email is sponsored by: Scholarships for Techies! Can't afford IT training? All 2003 ictp students receive scholarships. Get hands-on training in Microsoft, Cisco, Sun, Linux/UNIX, and more. www.ictp.com/training/sourceforge.asp _______________________________________________ Oscar-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/oscar-devel
------------------------------------------------------- This SF.net email is sponsored by: Scholarships for Techies! Can't afford IT training? All 2003 ictp students receive scholarships. Get hands-on training in Microsoft, Cisco, Sun, Linux/UNIX, and more. www.ictp.com/training/sourceforge.asp _______________________________________________ Oscar-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/oscar-devel
