Motorola 6806800C08B manual Checkpoint Director, Checkpoint Service NetPlane Core Services

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Checkpoint Service

NetPlane Core Services

 

 

In the case of asynchronous update option, one of the replicas is designated as the active replica. Data is always read from the active replica and there is no guarantee that all the other replicas contain identical data. A write call returns after updating the active replica.

In the case of synchronous update options, the call invoked to write to the replicas returns only when all replicas have been updated, i.e. either all replicas are updated or the call fails and no changes are made to the replicas.

The CPSv supports both collocated and non-collocated checkpoints. In case of checkpoints opened with collocated and asynchronous update option, it is up to the application to set a checkpoint to the active state. In all other cases the CPSv itself handles which checkpoint is currently active.

The Checkpoint Service defined by SAF does not support hot-standby. This means that the currently stand-by component is not notified of any changes made to the checkpoint. When the stand-by component gets active, it has to iterate through the respective checkpoint sections to get up-to-date. To overcome this drawback, the CPSv provides additional, non-SAF APIs which help to notify the stand-by component of changes and thus facilitate the implementation of a hot-stand-by.

2.5.2.2Architecture

The CPSv service consists of the following subparts:

zCheckpoint Director (CPD)

zCheckpoint Node Director (CPND)

zCheckpoint Agent (CPA)

2.5.2.2.1Checkpoint Director

The Checkpoint Director runs on the active system manager node. Its main tasks are:

zGenerating a unique ID for each new checkpoint created by applications

zMaintaining the list of nodes on which replicas of a particular checkpoint exist

zSelecting the Checkpoint Node Director (CPND) which oversees the active replica for each checkpoint

zCoordinating the creation and deletion of checkpoints

zMaintaining a repository for the CPSv policy and configuration-related information

There is an active and a stand-by CPD running respectively on the two system manager nodes. CPD uses the NCS Message based Checkpoint Service to keep the two synchronized and available for failover situations.

NetPlane Core Services Overview User’s Guide (6806800C08B)

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Contents NetPlane Core Services Overview Trademarks Contents NetPlane Core Services Overview User’s Guide 6806800C08B ContentsList of Tables Page Avantellis Main Software Components List of FiguresPage Abbreviations Overview of ContentsAbout this Manual HPM About this Manual Abbreviation DefinitionBold ConventionsNotation Description Comments and Suggestions Summary of ChangesAbout this Manual Notation Description Part Number Edition DescriptionAvantellis 3000 Series Overview IntroductionIntroduction Avantellis 3000 Series Software ArchitectureNetPlane Software Carrier Grade Linux Operating System Introduction Carrier Grade Linux Operating SystemPage Architectural Overview NetPlane Core ServicesCorresponding SAF AIS NCS Service Name Services Description NCS ServicesNetPlane Core Services NCS Services Message Distribution Service NetPlane Core Services Message Distribution ServiceNCS Service Name Description Leap Portability LayerNetPlane Core Services System Description Distribution of NCS Services in the Avantellis SystemSystem Description NCS DirectorsNCS Directors NCS Directors NetPlane Core ServicesSample Applications NetPlane Core Services NCS ServersNCS Servers System Description System Description NetPlane Core ServicesDescription Category Management AccessNetPlane Core ServicesManagement Access Management Access NetPlane Core Services Management Access Information FlowNetPlane Core Services SAF-Compliant NCS Services SAF-Compliant NCS ServicesAvailability Service Availability Manager Availability Service NetPlane Core ServicesAvailability Director NetPlane Core Services Checkpoint Service Checkpoint ServiceAvailability Node Director Availability AgentCheckpoint Director Checkpoint Service NetPlane Core ServicesCheckpoint Agent Message Queue ServiceCheckpoint Node Director Event Distribution Service NetPlane Core Services Event Distribution ServiceMessage Queue Director Message Queue Node DirectorNetPlane Core Services Global Lock Service Global Lock ServiceEvent Distribution Server Event Distribution AgentDistributed Tracing Service Motorola Complementary NCS ServicesGlobal Locking Director Global Lock Node DirectorDistributed Trace Server HPI Integration ServiceDistributed Trace Agent ArchitectureSystem Resource Monitoring Service Simple Software UpgradeSimple Software Upgrade NetPlane Core Services HPI Adaption Private Library HPLPersistent Store Server Persistent Store-Restore ServicePSSv Command Execution Functions Management Access ServicesManagement Access Services NetPlane Core Services System Description ParserObject Access Agent Management Access AgentManagement Access Server Message-Based Checkpointing ServiceCommand Line Interpreter Management Access Point Snmp Management Access PointInterface Service Interface Director Message Distribution ServiceInterface Node Director Interface AgentsNetPlane Core Services Message Distribution Service Message Distribution Service Software ComponentsLeap Portability Layer NetPlane Core Services Cancelling Application ThreadsLeap Portability Layer Implementation NotesPage Toolkit Contents Toolkit InstallationNCS Toolkit IntroductionBuilding the Samples Make CommandsDevelopment Host Prerequisites NCS Toolkit Building the SamplesParameters Make CommandsNCS ToolkitNCS Toolkit Running the Sample programs Running the Sample programsTarget Prerequisites Running the Sample Programs Setting LdlibrarypathSetting Ldlibrarypath NCS Toolkit Page Document Title Publication Number Related DocumentationMotorola Embedded Communications Computing Documents Document Title Version/Source Related SpecificationsRelated Documentation Related Specifications

6806800C08B specifications

The Motorola 68000 microprocessor, particularly the revision marked as 68000C08B, stands out as a seminal component in the evolution of computing technology. Introduced in 1979, the 68000 architecture laid the groundwork for many advanced systems, influencing a multitude of platforms, from personal computers to game consoles.

The Motorola 68000C08B features a 16-bit data bus and a 24-bit address bus, allowing for a memory addressing capability of up to 16 MB. This architecture was pioneering for its time, enabling more extensive and complex software applications than its predecessors. The C08 revision particularly emphasized optimizing power consumption while maintaining performance, making it ideal for embedded systems and portable devices.

One of the 68000's key characteristics is its unique register set, which allows for a versatile range of operations. It consists of 8 general-purpose data registers and 8 address registers. The architecture supports both integer and floating-point operations, thanks to an integrated instruction set that facilitates complex mathematical computations, crucial for applications in graphics and gaming.

In terms of performance, the 68000 processor operates at clock speeds ranging from 8 MHz to 16 MHz, depending on the specific variant. The instruction set architecture (ISA) is known for its orthogonality, meaning that most instructions can be used interchangeably across different registers. This design simplicity allows for efficient coding and faster execution times, a significant advantage for developers.

Another remarkable feature of the 68000C08B is its capability for multitasking and improved context switching. Its advanced memory management, combined with support for virtual memory in later implementations, catered to the needs of operating systems and real-time applications, making it suitable for both consumer electronics and industrial machinery.

The Motorola 68000 family also supports a variety of peripherals, enhancing its flexibility as a microcontroller. This compatibility allowed manufacturers to create diverse product lines, from keypads and mice to modems and hard drives.

In summary, the Motorola 68000C08B microprocessor not only advanced the landscape of computer technology in the late 20th century but also helped set the stage for future innovations through its architecture, performance capabilities, and versatility in numerous applications. Its legacy continues to influence modern computing paradigms, ensuring the 68000 remains an essential chapter in the history of microprocessors.
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