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

Michael Holzheu holzheu at linux.vnet.ibm.com
Mon Jan 13 04:58:31 EST 2014

On Fri, 10 Jan 2014 11:58:30 -0600
Cliff Wickman <cpw at sgi.com> wrote:


> 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.


More information about the kexec mailing list