#14 question about orgin application

[Anonymous]

now,likely, the run of the checkpoint image is independent of the orgin application. then, i want to ask that, is it possible that the checkpoint only saves the running state just-in-time, does not contain the binary of orgin application? If possible, when we have restore the state of appliation, we can continue to run the orgin application(whenever modified or not), Thanks

[Gene Cooperman]

The checkpoint saves whatever is in memory, along with a few pointers to disk, such as file descriptors with their current file offset. So, if your applications is self-modifying, this should not be a problem for DMTCP. It will still save a checkpoint image based on the contents of memory -- independently of the original executable file on disk. Is this the information that you were looking for? Best wishes, the DMTCP team.

[YUhuaQi]

Thanks for your reply. Ithink i see.

[Kapil Arya]

Hello,

Currently, it's not possible to just save the running state and not save the binary of the original application. The way DMTCP works is by saving all the memory pages of the process onto the checkpoint image along with some metadata. All this information is necessary for recreating the process image at restart time.

Do you have a particular reason for not checkpointing the application binary? If the primary reason for not doing this is the size of the application binary, then we have some good news for you. There is another related project which can be used with DMTCP for doing incremental checkpoints. You can check it out at http://hbict.sourceforge.net.

Thanks and sorry for the delay in responding!

-- Kapil