makedumpfile-1.5.9: Introduce parallel compression processing.

Louis Bouchard louis.bouchard at
Wed Oct 28 01:23:52 PDT 2015

Hello Kumagai-san,

Le 28/10/2015 07:31, Atsushi Kumagai a écrit :
> Hello,
> makedumpfile version 1.5.9 is released.
> Your comments/patches are welcome.
> Main new feature:
> o Parallel compression
>  - Add the new option "--num-threads" to enable parallel compression
>    for faster processing. This option intends parallel compression
>    while --split intends parallel i/o, they try to solve different
>    bottlenecks.
> o Change the way to choose the non-cyclic mode
>  - Add the new option "--work-dir" to specify the directory used to
>    store the bitmap. This is the alternative to the combination of
>    --non-cyclic and TMPDIR.
> o Support new kernels
>  - The supported kernel is updated to 4.1 in this version.
>    At first I'm going to extend the supported version to 4.2, but
>    I found an issue that makedumpfile seems to exclude necessary pages
>    by mistake on linux 4.2. When crash-7.1.3 reads that filtered dump file,
>    the following message is shown.
>       crash: page excluded: kernel virtual address: f3fe0000  type: "fill_task_struct"
>    This will be fixed in the next version.

Have you fixed the 4.2 kernel issue already or you intend to work on it in the
future ?

Both Debian and Ubuntu run 4.2 kernel so if waiting for a fix is acceptable I
would rather bring in a 1.5.9 + patch version.

Kind regards,


Louis Bouchard
Software engineer, Cloud & Sustaining eng.
Canonical Ltd
Ubuntu developer                       Debian Maintainer
GPG : 429D 7A3B DD05 B6F8 AF63  B9C4 8B3D 867C 823E 7A61

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