svn commit: r316938 - head/sbin/savecore

[Slawa Olhovchenkov]

On Fri, Apr 14, 2017 at 01:49:51PM -0600, Alan Somers wrote:

> On Fri, Apr 14, 2017 at 1:41 PM, Ngie Cooper <ngie at freebsd.org> wrote:
> > Author: ngie
> > Date: Fri Apr 14 19:41:48 2017
> > New Revision: 316938
> > URL: https://svnweb.freebsd.org/changeset/base/316938
> >
> > Log:
> >   savecore: fix space calculation with respect to `minfree` in check_space(..)
> >
> >   - Use strtoll(3) instead of atoi(3), because atoi(3) limits the
> >     representable data to INT_MAX. Check the values received from
> >     strtoll(3), trimming trailing whitespace off the end to maintain
> >     POLA.
> >   - Use `KiB` instead of `kB` when describing free space, total space,
> >     etc. I am now fully aware of `KiB` being the IEC standard for 1024
> >     bytes and `kB` being the IEC standard for 1000 bytes.
> >   - Store available number of KiB in `available` so it can be more
> >     easily queried and compared to ensure that there are enough KiB to
> >     store the dump image on disk.
> >   - Print out the reserved space on disk, per `minfree`, so end-users
> >     can troubleshoot why check_space(..) is reporting that there isn't
> >     enough free space.
> >
> >   MFC after:    7 weeks
> >   Reviewed by:  Anton Rang <rang at acm.com> (earlier diff), cem (earlier diff)
> >   Tested with:  positive/negative cases (see review); make tinderbox
> >   Sponsored by: Dell EMC Isilon
> >   Differential Revision:        D10379
> 
> The free space calculation is still uselessly conservative, because it
> doesn't account for the fact that core dumps will always be either
> spare or compressed.  The result is that savecore will frequently
> refuse to save corefiles even when there's plenty of space.  I
> proposed removing the space check altogether in
> https://reviews.freebsd.org/D2587.  However, I agreed to wait until
> after the compressed core dump feature was merged, because then mostly
> accurate space checks will be possible.  AFAIK the compressed core
> dump feature still hasn't been finished.

Is posible (in the future) to use multiple swaps (on multiple disks)
for save core dumps?