Distributed Shared Memory on Ericsson Labs

Distributed Shared Memory on Ericsson Labs

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  Distributed Shared Memory A labs.ericsson.com API http://labs.ericsson.com/apis/distributed-shared-memory/
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  ericsson labs APIs Maps & positioning communication security Mobile Mobile SMS Send & Mobile Group Voice Mobile Web Security Oauth2 Location Maps Receive Push Mixer Bootstrap CAPTCHA Framework Web Async Identity Management Key Management Maps Voice Framework Service Web technologies NFC & sensors User & network information Web Web Background Mobile Sensor Mobile Network Tag Tool Connectivity EventSource Service Actuator Link Identification Probe Web Device Mobile Network Distributed Web Real-Time Real- Sensor Networking Connectivity Shared Memory Communication Application Platform Look-up Look- Machine learning Media and graphics Face Cluster Text-to-Speech Text- to- Detector Constructor © Ericsson AB 2010 | Page 2
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  Distributed shared memory › Distributed Shared Memory enables a distributed in- memory database for JavaScript applications – Get a replica of a DSM storage with a specified address from a DSM server – Register a listener and be notified when data is changes by other users – Modify data locally and synchronize changes in the background with other replicas › Merge conflicts are automatically resolved © Ericsson AB 2010 | Page 3
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  Why distributed sharedmemory? › Let web developers focus on developing highly interactive and responsive web-based collaboration software without having to deal with complicated issues such as – networking protocols – database management – concurrency control › Also, using a local replica where data can be modified directly without a lock or blocking improves user experience › Synchronizing application states among multiple clients › Implement group-wares or collaborative web services supporting simultaneous real-time interactions © Ericsson AB 2010 | Page 4
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  Main Features › Makesit possible for multiple JavaScript clients to address and manipulate the same data at the same › Plain JavaScript Lib (no browser plug-in required) › High performance and low delay › Optimistic replication to resolve merge conflicts › Event-driven (register a listener and be notified when data change) › Support for both ordered arrays/lists and unordered key-value hash tables › Support for both persistent storage (disk) and transient data (RAM) › Automatic garbage collection › Time-to-live (specify how long time a value should be stored) › Possibility to link DSM storages to build graph databases © Ericsson AB 2010 | Page 5
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  Use cases Examples ofusage › E-learning › Tele-care, e.g. remote health care and specialist consultation, remote monitoring etc. › Call center support › Collaborative work, e.g. a shared whiteboard or other collaborative editing systems etc. © Ericsson AB 2010 | Page 6
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  Merge conflicts areresolved › All clients (and servers) DSM SW contains predefined rules how to resolve conflicts “Adjust” or transform incoming operation to match local changes © Ericsson AB 2010 | Page 7
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  JavaScript API › Simpleand easy to use to API // get a replica of hash://simpleTest var hash = memCtrl.get(“hash://simpleTest”); // update the web page when the replica is cloned hash.onReady = function () { document.getElementById(“myTextfield”).value = hash.get(“myKey”); }; // handle changes to the replica hash.onUpdate = function (op) { document.getElementById(“myTextfield”).value = op.value; }; // update the local replica hash.set(“myKey”, “myValue”); // send the operation to all other replica clients in the background hash.submit(); © Ericsson AB 2010 | Page 8
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  Example applications Shared Whiteboards Collaborative Workspaces Shared JavaScript Apps, e.g. a Shared Map Widget © Ericsson AB 2010 | Page 9
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  © Ericsson AB2010 | Page 10