makedumpfile-1.1.6: linux-2.6.22 support

Ken'ichi Ohmichi oomichi at
Sun Aug 12 22:18:58 EDT 2007


makedumpfile version 1.1.6 is released.
Please test it. Your opinions/comments are welcome.

Explanation of makedumpfile:
  To shorten the size of the dumpfile and the time of creating the
  dumpfile, makedumpfile copies only the necessary pages for analysis
  to the dumpfile from /proc/vmcore. You can specify the kind of
  unnecessary pages with dump_level. If you want to shorten the size
  further, enable the compression of the page data.


o linux-2.6.22 support.
  The method for getting the member offset of "page.mapping" is
  applied for linux-2.6.22.
  Old makedumpfile assumed that there was "mapping" in the first
  union in structure "page". But on linux-2.6.22, there is "mapping"
  in the second union, because "_mapcount" and structure for slub
  are packed in the first union. Then, new makedumpfile gets the
  offset by searching "mapping" in each union.

o Change the check method of free_pages for linux-2.6.21 or later.
  On linux-2.6.21 or later, the number of free_pages (vm_stat[0])
  is sometimes different from the one of the pages listed in
  "free_area" actually, because the former is flushed asynchronously.
  Then, new makedumpfile doesn't check these numbers, and confirms
  the free_pages only by checking whether the list "free_area" is
  not corrupted.

o Some cleanups
  - Cleanup the description for '--message-level' by Akira Imamura.
  - Cleanup the structures DumpInfo and vm_table.
  - Cleanup the dwarf method.
  - Cleanup page_to_pfn() method.

You can download the latest makedumpfile(ver. 1.1.6) from the following URL.
Details of the change are written on the CVS page of the following site.

Method of installation:
  You can compile the makedumpfile command as follows;
  1. "tar -zxvf makedumpfile-1.1.6.tar.gz"
  2. "cd makedumpfile"
  3. "make; make install"

  makedumpfile [-c] [-E] [-d dump_level] [-x vmlinux] dump_mem dump_file

  If you want to exclude pages filled by zero, cache pages, user pages
  and free pages and to enable compression, please execute the following

  # makedumpfile -c -d 31 -x vmlinux /proc/vmcore dumpfile

Ken'ichi Ohmichi

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