From mboxrd@z Thu Jan 1 00:00:00 1970 From: Amerigo Wang Date: Mon, 10 Aug 2009 03:11:34 +0000 Subject: Re: [Patch 0/7] Implement crashkernel=auto Message-Id: <4A7F8FE6.9030709@redhat.com> List-Id: References: <20090805112123.6552.73574.sendpatchset@localhost.localdomain> <20090805140408.GJ7259@hmsreliant.think-freely.org> <4A7A3A78.7080200@redhat.com> <4A7A506B.2060008@redhat.com> <4A7A70E5.2010204@redhat.com> <4A7A7A0F.6070906@redhat.com> <4A7A9E54.60705@redhat.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: "Eric W. Biederman" Cc: Neil Horman , linux-kernel@vger.kernel.org, tony.luck@intel.com, linux-ia64@vger.kernel.org, akpm@linux-foundation.org, Ingo Molnar , Anton Vorontsov , Andi Kleen , Bernhard Walle , Kexec Mailing List Eric W. Biederman wrote: > Let me put this concrete proposal on the table. > > The problem: > > With the current set of crashkernel= options we are asking the > distribution installer to perform magic. Moving as much of this logic > into a normal init script for better maintenance is desirable. > > My proposal: > > Implement crashkernel=max which reserves as much memory as is > reasonable for a crash kernel, without seriously affecting stability, > performance, and reliability. > This is almost exactly what I want with crashkernel=auto.... So there's no big difference, except the name. > As an initial approximation I would use a 32nd of low memory. > Hmm, I think Bernhard's proposal is fine for this case, i.e. we can introduce a new syntax, "crashkernel=>>X" which means we reserve 1/2^X of system memory. What do you think? > In addition implement: > > /sys/kernel/crash_size > > That can be written to (with enough privileges when no crash kernel is > loaded) reduce the amount of memory reserved by the crash kernel. > Yeah, this is nice! Thanks.