From: Paul H. Hargrove (PHHargrove_at_lbl_dot_gov)
Date: Thu Mar 25 2010 - 17:20:31 PDT
TK, I am sorry I didn't get the chance to answer this one when you asked me directly 2 days ago - I am up against some deadlines right now. To answer your question: In the function you ask about we are dealing only with memory regions created by mmap() of a file. Therefore all the "clean" pages already exist somewhere on disk in the file that has been mmap()ed. This includes the executable file and shared libraries that were mmap()ed in prior to the start of main(). As with open files, BLCR makes the (optimistic) assumption that the file will still exist, unmodified, at the time of the restart. However, one can ensure that even the "clean" pages will be stored with the checkpoint by passing --save-all. -Paul TK wrote: > Hi , all. I am trying to adding my own code into BLCR for some > experiments. > When I was reading the code of "cr_save_mmaps_data" function in > cr_module/cr_mmaps.c, I found the comment /* dump the dirty pages */ . > I am wondering you dump only the dirty pages only? It will not be > enough info for restart. Or the other pages are dumped else where? If > so, where is it? > Thank you. -- Paul H. Hargrove PHHargrove_at_lbl_dot_gov Future Technologies Group Tel: +1-510-495-2352 HPC Research Department Fax: +1-510-486-6900 Lawrence Berkeley National Laboratory