From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [PATCH 1/5] trace, RAS: Add basic RAS trace event Date: Wed, 16 Apr 2014 15:10:31 +0200 Message-ID: <20140416131030.GC16741@pd.tnic> References: <1395985981-20476-1-git-send-email-gong.chen@linux.intel.com> <1395985981-20476-2-git-send-email-gong.chen@linux.intel.com> <20140409194654.GR6529@pd.tnic> <20140416063301.GC11297@gchen.bj.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Received: from mail.skyhub.de ([78.46.96.112]:49771 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755622AbaDPNKg (ORCPT ); Wed, 16 Apr 2014 09:10:36 -0400 Content-Disposition: inline In-Reply-To: <20140416063301.GC11297@gchen.bj.intel.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Chen, Gong" Cc: tony.luck@intel.com, m.chehab@samsung.com, rostedt@goodmis.org, linux-acpi@vger.kernel.org, arozansk@redhat.com On Wed, Apr 16, 2014 at 02:33:01AM -0400, Chen, Gong wrote: > On Wed, Apr 09, 2014 at 09:46:54PM +0200, Borislav Petkov wrote: > > > > menuconfig RAS > > bool "Reliability, Availability, Serviceability features" > > help > > > > How about this: Good. Just nitpicks below: > Reliability, availability, and serviceability (RAS) is a computer > hardware engineering term. Computers designed with higher levels > of RAS have a multitude of features that protect data integrity > and help them stay available for long periods of time without > failure. > > Reliability can be defined as the probability that it will produce s/it/the system/. "it" is kinda misleading as to what we refer to. > correct outputs up to some given time. Reliability is enhanced by > features that help to avoid, detect and repair hardware faults. > > Availability is the probability a system is operational at a given > time, i.e. the amount of time a device is actually operating as the > percentage of total time it should be operating. > > Serviceability or maintainability is the simplicity and speed with > which a system can be repaired or maintained; if the time to repair > a failed system increases, then availability will decrease. Nice! > Note that reliability and availability are distinct concepts: capitalized: ... that Reliability and Availability are ... > Reliability is a measure of the ability of a system to function > correctly, including avoiding data corruption, whereas availability ditto: Availability > measures how often it is available for use, even though it may not > be functioning correctly. For example, a server may run forever and > so have ideal availability, but may be unreliable, with frequent > data corruption. Very good description! :-) -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. --