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ddsf:public:guidebook:06_append:02_quality_of_service:destination_order [2021/07/14 15:46] murphy ↷ Links adapted because of a move operation |
ddsf:public:guidebook:06_append:02_quality_of_service:destination_order [2021/07/14 15:55] (current) murphy ↷ Links adapted because of a move operation |
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| [[ddsf:public:guidebook:06_append:02_quality_of_service:start|return to the Quality of Service (QoS) Parameters ]] | [[ddsf:public:guidebook:06_append:02_quality_of_service:start|return to the Quality of Service (QoS) Parameters ]] | ||
| - | The DESTINATION_ORDER policy controls how each [[ddsf:private:guidebook:06_append:glossary:s:subscriber|subscriber]] resolves the final value of a data [[ddsf:public:guidebook:06_append:glossary:i:instance|instance]] that is written by multiple ''DataWriter'' | + | The DESTINATION_ORDER policy controls how each [[ddsf:public:guidebook:06_append:glossary:s:subscriber|subscriber]] resolves the final value of a data [[ddsf:public:guidebook:06_append:glossary:i:instance|instance]] that is written by multiple ''DataWriter'' |
| - | objects (which may be associated with different ''[[ddsf:private:guidebook:06_append:glossary:p:publisher|Publisher]]'' objects) running on different nodes. | + | objects (which may be associated with different ''[[ddsf:public:guidebook:06_append:glossary:p:publisher|Publisher]]'' objects) running on different nodes. |
| - | The setting BY_RECEPTION_TIMESTAMP indicates that, assuming the [[ddsf:private:guidebook:06_append:glossary:o:ownership_qos|OWNERSHIP]] policy allows it, the latest received | + | The setting BY_RECEPTION_TIMESTAMP indicates that, assuming the [[ddsf:public:guidebook:06_append:glossary:o:ownership_qos|OWNERSHIP]] policy allows it, the latest received |
| value for the instance should be the one whose value is kept. This is the default value. | value for the instance should be the one whose value is kept. This is the default value. | ||
| The setting BY_SOURCE_TIMESTAMP indicates that, assuming the OWNERSHIP policy allows it, a timestamp placed at | The setting BY_SOURCE_TIMESTAMP indicates that, assuming the OWNERSHIP policy allows it, a timestamp placed at | ||
| - | the source should be used. This is the only setting that, in the case of concurrent same-[[ddsf:public:guidebook:06_append:02_quality_of_service:ownership_strength|strength]] ''DataWriter'' objects updating the same instance, ensures all subscribers will end up with the same final value for the instance. The mechanism to set the source timestamp is [[ddsf:private:guidebook:06_append:glossary:m:midware|middleware]] dependent. | + | the source should be used. This is the only setting that, in the case of concurrent same-[[ddsf:public:guidebook:06_append:02_quality_of_service:ownership_strength|strength]] ''DataWriter'' objects updating the same instance, ensures all subscribers will end up with the same final value for the instance. The mechanism to set the source timestamp is [[ddsf:public:guidebook:06_append:glossary:m:midware|middleware]] dependent. |
| The value offered is considered compatible with the value requested if and only if the inequality ''offered kind >= requested kind'' evaluates to ''TRUE''. For the purposes of this inequality, the values of DESTINATION_ORDER ''kind'' are considered ordered such that ''BY_RECEPTION_TIMESTAMP < BY_SOURCE_TIMESTAMP''. | The value offered is considered compatible with the value requested if and only if the inequality ''offered kind >= requested kind'' evaluates to ''TRUE''. For the purposes of this inequality, the values of DESTINATION_ORDER ''kind'' are considered ordered such that ''BY_RECEPTION_TIMESTAMP < BY_SOURCE_TIMESTAMP''. | ||