Problems with big graphs / many partitions


my problem is that I can only partition small graphs into only a few partitions. I can partition a graph with ~30000 nodes and ~70000 edges into 6 partitions (using METIS_PartGraphKway(...)), but when I try to partition it in to >6 partitions, it exits with a segmentation fault.
Metis tells me several times that I "just increased the maxndoms: ..." and then exits. I don't know exactly what that means. With gdb I tried to find the point of termination and it seems that Metis doesn't return from "unlink_chunk(...)" in the file "dlmalloc.c".
I have this error in Metis-5.0pre2 as well as in the stable version. Did anyone have this problem before and knows how to solve it?

Thanks in advance,


RE: Does you graph have any zero

Does you graph have any zero weight edges and/or negative edges?
How about vertex weights, does it have any? If yes, how are they distributed?

RE: Having a similar probem


My graph is only ~6,000 vertices and 20,000 edges. There are no weights on the vertices. The edges have weights > 0.
I call METIS_PartGraphKway() from my program and sometimes (not always) get the message "You just increased the maxndoms: 6 5". It is interesting that I get it only when I partition into 24 regions (my program tries all numbers of regions from 2 to a certain number > 24).

What are the numbers "6 5"? Should I assume that the partitioning did not succeed if I see this message? If so, how do I go about correcting this?

Thank you,