[PATCH 1/2 V2] raw i/o and root device to use less memory

Cliff Wickman cpw at sgi.com
Mon Jan 13 08:30:33 EST 2014

On Mon, Jan 13, 2014 at 10:58:31AM +0100, Michael Holzheu wrote:
> On Fri, 10 Jan 2014 11:58:30 -0600
> Cliff Wickman <cpw at sgi.com> wrote:
> [snip]
> > Use O_DIRECT (raw) i/o for the dump and for the bitmaps file, so that writing
> > to those files does not allocate kernel memory for page cache.
> Hello Cliff,
> Have you tested O_DIRECT together with the new vmcore mmap interface?
> IIRC when we tried O_DIRECT together with mmap for some reason it did
> not work.
> Michael

Hi Michael,

  How new of a kernel do I need?  i.e. how 'new' of an mmap interface?
  The latest kernel I used was 3.0.93 (sle11sp3).
  And makedumpfile was 1.5.5.

Cliff Wickman
cpw at sgi.com
(651) 683-3824

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