diff --git a/docu/mars-architecture-guide.lyx b/docu/mars-architecture-guide.lyx index 2fd20ebc..a4807ae6 100644 --- a/docu/mars-architecture-guide.lyx +++ b/docu/mars-architecture-guide.lyx @@ -473,7 +473,206 @@ name "chap:Management-Summary" \end_layout \begin_layout Standard -TBD +This guide is about +\series bold +investments and long-term follow-up cost +\series default + in the range of +\series bold +millions +\series default + of € or $. + It tries to guide you through the jungle of storage solutions and their + features, by focussing at +\series bold +fundamental principles +\series default + and high-level structures, called +\series bold +architecture +\series default +. +\end_layout + +\begin_layout Standard +For +\series bold +HA enterprise-critical data +\series default + in the range of +\series bold +petabytes +\series default +, different storage architectures are leading to very different properties + in the +\series bold +cost and risk dimensions +\series default +. +\end_layout + +\begin_layout Standard +\begin_inset Flex Custom Color Box 3 +status open + +\begin_layout Plain Layout +\begin_inset Argument 1 +status open + +\begin_layout Plain Layout + +\series bold +Provably best HA / Cloud Storage architecture +\end_layout + +\end_inset + +By intuitive explanations as well as mathematical arguments, this guide + shows that +\end_layout + +\begin_layout Itemize +Permanent +\series bold +minimization of the distances +\series default + between storage and the compute nodes will both +\series bold +increase reliablity and reduce cost at the same time +\series default +. +\end_layout + +\begin_layout Itemize +When applicable for a certain use case, the best architectural model is + +\series bold +sharding +\series default + on top of +\series bold +local storage +\series default +. + It can easily save a cost factor of about 2, while increasing +\series bold +architectural reliability +\series default + at the same time. +\end_layout + +\begin_layout Itemize +When the so-called +\series bold +FlexibleSharding +\series default + variant of the sharding model is combined with a novel load balancing method + called +\series bold +Football +\series default +, it can deliver a very similar level of +\series bold +flexibility +\series default + than network-centric BigCluster architectures are promising. +\end_layout + +\begin_layout Itemize +By both intuitive and mathematical explanations, and contrary to some contempora +ry belief, you will learn +\series bold +\emph on +why +\emph default + BigCluster architectures are generally worse +\series default + in practically any dimension. + There exist certain use cases where BigCluster cannot be explicitly recommended. +\end_layout + +\begin_layout Itemize +When built and dimensioned properly, +\series bold +cross-datacenter replication +\series default + and/or +\series bold +geo-redundancy +\series default + will +\emph on +not +\emph default + double TCO = Total Cost of Ownership, but can cost roughly about the same + as local redundancy in the same datacenter. + The key is a certain class of +\series bold +wide-area distribution of resources +\series default + +\emph on +in place of +\emph default + local replication. +\end_layout + +\begin_layout Itemize +When cross-datacenter replication and/or geo-redundancy is required, the + so-called +\series bold +ability for butterfly +\series default + leads to further HA improvements. +\end_layout + +\begin_layout Itemize +Object-based +\series bold +Cloud Storage +\series default + can also be built on top of a sharding model. +\end_layout + +\begin_layout Itemize +You will learn +\series bold +why OpenSource component-based storage systems +\series default + are much cheaper than commercial storage appliances (up to +\emph on +factors +\emph default +), at least when you need a few petabytes of storage. + Alone by relinquishing Vendor-Lock-In and going to RAID-based Linux storage, + invest will typically decrease by factors between 3 and 10. + By going to a +\family typewriter +LocalSharding +\family default + or +\family typewriter +FlexibleSharding +\family default + model, where possible, +\emph on +another +\emph default + decrease factor of about 2 is typically possible. +\end_layout + +\end_inset + + +\end_layout + +\begin_layout Standard +\noindent +In addition, this guide explains the ideas behind the OpenSource components + Football on top of MARS. + It can be used for replication over short to very long distances, as well + as for load balancing via background data migration while your services + are running. \end_layout \begin_layout Chapter