On 3/5/2015 5:21 PM, Gene Cooperman wrote: > Hi Eliot, > At least when I reproduced the bug, I migrated from an AMD machine > to an Intel one. The two filename prefixes that I saw were: > /usr/lib/jvm/java-7-openjdk-common [ on the AMD machine ] > /usr/lib/jvm/java-6-openjdk-common [ on the Intel machine ] > So, this first fix is for an existing bug in DMTCP. (When we > re-create a shared memory section, we don't check if the backing > file is a legal filename. Our fix will be to map it as private in that case. > The checkpoint image will then carry with it all of the memory from > java-7. Hopefully, DMTCP will then restart correctly on the > destination machine, even if there is _no_ java at all on the destination. > In your own case, you might be seeing the same issue due to > differing NFS mount points, just as you describe. But the same > solution should apply. > > I agree with you that we'll then need to test this solution, and > sse if there is a further problem. If we find a further problem, > we might need to then add a specialized plugin to help Java adapt to the > new environment. For example, if the memory segments refer to a > filename on the source Java machine, and _if_ the jvm tries to open > them _after_ restart on the destination machine, that would be a problem. > DMTCP plugins are designed for cases just like this: adapting to a new > environment on restart. > > So, we'll begin with the DMTCP bug fix, and then see if we also > need to add a new plugin specialized for Java.
Makes sense -- thank you, Gene! Eliot ------------------------------------------------------------------------------ Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ Dmtcp-forum mailing list Dmtcp-forum@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dmtcp-forum
