Traditional theory and practice of write-ahead logging and of database recovery techniques revolve around three failure classes: transaction failures resolved by rollback; system failures (typically software faults) resolved by restart with log analysis, “redo,” and “undo” phases; and media failures (typically hardware faults) resolved by restore operations that combine multiple types of backups and log replay. The recent addition of single-page failures and single-page recovery has opened new opportunities far beyond its original aim of immediate, lossless repair of single-page wear-out in novel or traditional storage hardware. In the contexts of system and media failures, efficient single-page recovery enables on-demand incremental “redo” and “undo” as part of system restart or media restore operations. This can give the illusion of practically instantaneous restart and restore: instant restart permits processing new queries and updates seconds after system reboot and instant restore permits resuming queries and updates on empty replacement media as if those were already fully recovered. In addition to these instant recovery techniques, the discussion introduces much faster offline restore operations without slowdown in backup operations and with hardly any slowdown in log archiving operations. The new restore techniques also render differential and incremental backups obsolete, complete backup commands on the database server practically instantly, and even permit taking full backups without imposing any load on the database server. Table of Contents: Preface / Acknowledgments / Introduction / Related Prior Work / Single-Page Recovery / Applications of Single-Page Recovery / Instant Restart after a System Failure / Single-Pass Restore / Applications of Single-Pass Restore / Instant Restore after a Media Failure / Multiple Failures / Conclusions / References / Author Biographies

Traditional theory and practice of write-ahead logging and of database recovery focus on three failure classes: transaction failures (typically due to deadlocks) resolved by transaction rollback; system failures (typically power or software faults) resolved by restart with log analysis, "redo," and "undo" phases; and media failures (typically hardware faults) resolved by restore operations that combine multiple types of backups and log replay. The recent addition of single-page failures and single-page recovery has opened new opportunities far beyond the original aim of immediate, lossless repair of single-page wear-out in novel or traditional storage hardware. In the contexts of system and media failures, efficient single-page recovery enables on-demand incremental "redo" and "undo" as part of system restart or media restore operations. This can give the illusion of practically instantaneous restart and restore: instant restart permits processing new queries and updates seconds after system reboot and instant restore permits resuming queries and updates on empty replacement media as if those were already fully recovered. In the context of node and network failures, instant restart and instant restore combine to enable practically instant failover from a failing database node to one holding merely an out-of-date backup and a log archive, yet without loss of data, updates, or transactional integrity. In addition to these instant recovery techniques, the discussion introduces self-repairing indexes and much faster offline restore operations, which impose no slowdown in backup operations and hardly any slowdown in log archiving operations. The new restore techniques also render differential and incremental backups obsolete, complete backup commands on a database server practically instantly, and even permit taking full up-to-date backups without imposing any load on the database server. Compared to the first version of this book, this second edition adds sections on applications of single-page repair, instant restart, single-pass restore, and instant restore. Moreover, it adds sections on instant failover among nodes in a cluster, applications of instant failover, recovery for file systems and data files, and the performance of instant restart and instant restore.

We all recognize the countless benefits of differentiated instruction. The challenge is in its implementation. Faced with a classroom of 25 students-each with very different needs-how can we possibly keep every student on track and motivated? Through formative assessment and efficient follow-up instruction. This start-to-finish guide will show you how through seven classroom-tested practices for maximizing student learning. Experts on this subject, Leslie Laud and Pooja Patel demonstrate how to Establish new classroom norms Involve students in the use of assessment data and feedback to inform their next steps Clarify end-of-unit criteria to help map learning progression Apply assessment data to group students for tiered activities Differentiate assignments based on student readiness, characteristics, and interest Best of all, Using Formative Assessment to Differentiate Middle School Literacy Instruction is packed with vignettes, sample worksheets, and charts to assist you through each step in the process. Armed with this tool kit, you'll quickly discover new ways to keep all students engaged in their learning. Book jacket.

In this clear-eyed, candid, and ultimately reassuring

Get up to speed on Apache Accumulo, the flexible, high-performance key/value store created by the National Security Agency (NSA) and based on Google’s BigTable data storage system. Written by former NSA team members, this comprehensive tutorial and reference covers Accumulo architecture, application development, table design, and cell-level security. With clear information on system administration, performance tuning, and best practices, this book is ideal for developers seeking to write Accumulo applications, administrators charged with installing and maintaining Accumulo, and other professionals interested in what Accumulo has to offer. You will find everything you need to use this system fully. Get a high-level introduction to Accumulo’s architecture and data model Take a rapid tour through single- and multiple-node installations, data ingest, and query Learn how to write Accumulo applications for several use cases, based on examples Dive into Accumulo internals, including information not available in the documentation Get detailed information for installing, administering, tuning, and measuring performance Learn best practices based on successful implementations in the field Find answers to common questions that every new Accumulo user asks

Using Android as a reference, this book teaches the development of mobile apps designed to be responsive, trustworthy and robust, and optimized for maintainability. As the share of mission-critical mobile apps continues to increase in the ever-expanding mobile app ecosystem, it has become imperative that processes and procedures to assure their reliance are developed and included in the software life cycle at opportune times. Memory, CPU, battery life and screen size limitations of smartphones coupled with volatility associated with mobile environments underlines that the quality assurance strategies that proved to be successful for desktop applications may no longer be effective in mobile apps. To that effect, this book lays a foundation upon which quality assurance processes and procedures for mobile apps could be devised. This foundation is composed of analytical models, experimental test-beds and software solutions. Analytical models proposed in the literature to predict software quality are studied and adapted for mobile apps. The efficacy of these analytical models in prejudging the operations of mobile apps under design and development is evaluated. A comprehensive test suite is presented that empirically assesses a mobile app’s compliance to its quality expectations. Test procedures to measure quality attributes such as maintainability, usability, performance, scalability, reliability, availability and security, are detailed. Utilization of test tools provided in Android Studio as well as third-party vendors in constructing the corresponding test-beds is highlighted. An in-depth exploration of utilities, services and frameworks available on Android is conducted, and the results of their parametrization observed through experimentation to construct quality assurance solutions are presented. Experimental development of some example mobile apps is conducted to gauge adoption of process models and determine favorable opportunities for integrating the quality assurance processes and procedures in the mobile app life cycle. The role of automation in testing, integration, deployment and configuration management is demonstrated to offset cost overheads of integrating quality assurance process in the life cycle of mobile apps.

* One of the first books to cover MySQL 5 in depth * Foregos reiteration of the basics found in other books, and concentrates on MySQL’s advanced applications in enterprise environments * Doubles as a reference for users interested in having a thorough guide to configuration directives, commands, and features at their disposal

A Patterns Approach to Designing Distributed Systems and Solving Common Implementation Problems More and more enterprises today are dependent on cloud services from providers like AWS, Microsoft Azure, and GCP. They also use products, such as Kafka and Kubernetes, or databases, such as YugabyteDB, Cassandra, MongoDB, and Neo4j, that are distributed by nature. Because these distributed systems are inherently stateful systems, enterprise architects and developers need to be prepared for all the things that can and will go wrong when data is stored on multiple servers--from process crashes to network delays and unsynchronized clocks. Patterns of Distributed Systems describes a set of patterns that have been observed in mainstream open-source distributed systems. Studying the common problems and the solutions that are embodied by the patterns in this guide will give you a better understanding of how these systems work, as well as a solid foundation in distributed system design principles. Featuring real-world code examples from systems like Kafka and Kubernetes, these patterns and solutions will prepare you to confidently traverse open-source codebases and understand implementations you encounter "in the wild." Review the building blocks of consensus algorithms, like Paxos and Raft, for ensuring replica consistency in distributed systems Understand the use of logical timestamps in databases, a fundamental concept for data versioning Explore commonly used partitioning schemes, with an in-depth look at intricacies of two-phase-commit protocol Analyze mechanisms used in implementing cluster coordination tasks, such as group membership, failure detection, and enabling robust cluster coordination Learn techniques for establishing effective network communication between cluster nodes. Along with enterprise architects and data architects, software developers working with cloud services such as Amazon S3, Amazon EKS, and Azure CosmosDB or GCP Cloud Spanner will find this set of patterns to be indispensable. Register your book for convenient access to downloads, updates, and/or corrections as they become available. See inside book for details.

High Performance MySQL is the definitive guide to building fast, reliable systems with MySQL. Written by noted experts with years of real-world experience building very large systems, this book covers every aspect of MySQL performance in detail, and focuses on robustness, security, and data integrity. High Performance MySQL teaches you advanced techniques in depth so you can bring out MySQL's full power. Learn how to design schemas, indexes, queries and advanced MySQL features for maximum performance, and get detailed guidance for tuning your MySQL server, operating system, and hardware to their fullest potential. You'll also learn practical, safe, high-performance ways to scale your applications with replication, load balancing, high availability, and failover. This second edition is completely revised and greatly expanded, with deeper coverage in all areas. Major additions include: Emphasis throughout on both performance and reliability Thorough coverage of storage engines, including in-depth tuning and optimizations for the InnoDB storage engine Effects of new features in MySQL 5.0 and 5.1, including stored procedures, partitioned databases, triggers, and views A detailed discussion on how to build very large, highly scalable systems with MySQL New options for backups and replication Optimization of advanced querying features, such as full-text searches Four new appendices The book also includes chapters on benchmarking, profiling, backups, security, and tools and techniques to help you measure, monitor, and manage your MySQL installations.