Distributed programs are often written as a collection of communicating modules. For example, to use Java RMI, programs are divided into objects which can be remotely referenced. Yet, in many cases, it would be desirable to write the program without the program structure being driven by distribution decisions. If distribution is decoupled from program structure, the programming language must allow communication throughout a program's structure, instead of at a few known points. This situation is simplified if the programming language provides a uniform programming model for local and remote values (location transparency). We present Distributed Orc, which offers location transparency, and distributes program operations automatically in cooperation with the execution environment. By eliminating any special semantics of remote values, Distributed Orc enables programmers to write cohesive distributed programs, rather than programs artificially divided at distribution boundaries. Distributed Orc is derived from the Orc language, a (centralized) concurrent orchestration language.
{"title":"Implicitly Distributing Pervasively Concurrent Programs: Extended abstract","authors":"John A. Thywissen, A. Peters, W. Cook","doi":"10.1145/2957319.2957370","DOIUrl":"https://doi.org/10.1145/2957319.2957370","url":null,"abstract":"Distributed programs are often written as a collection of communicating modules. For example, to use Java RMI, programs are divided into objects which can be remotely referenced. Yet, in many cases, it would be desirable to write the program without the program structure being driven by distribution decisions. If distribution is decoupled from program structure, the programming language must allow communication throughout a program's structure, instead of at a few known points. This situation is simplified if the programming language provides a uniform programming model for local and remote values (location transparency). We present Distributed Orc, which offers location transparency, and distributes program operations automatically in cooperation with the execution environment. By eliminating any special semantics of remote values, Distributed Orc enables programmers to write cohesive distributed programs, rather than programs artificially divided at distribution boundaries. Distributed Orc is derived from the Orc language, a (centralized) concurrent orchestration language.","PeriodicalId":316230,"journal":{"name":"First Workshop on Programming Models and Languages for Distributed Computing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129338522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vitor Enes, Carlos Baquero, Paulo Sérgio Almeida, Ali Shoker
State-based CRDTs allow updates on local replicas without remote synchronization. Once these updates are propagated, possible conflicts are resolved deterministically across all replicas. δ-CRDTs bring significant advantages in terms of the size of messages exchanged between replicas during normal operation. However, when a replica joins the system after a network partition, it needs to receive the updates it missed and propagate the ones performed locally. Current systems solve this by exchanging the full state bidirectionally or by storing additional metadata along the CRDT. We introduce the concept of join-decomposition for state-based CRDTs, a technique orthogonal and complementary to delta-mutation, and propose two synchronization methods that reduce the amount of information exchanged, with no need to modify current CRDT definitions.
{"title":"Join Decompositions for Efficient Synchronization of CRDTs after a Network Partition: Work in progress report","authors":"Vitor Enes, Carlos Baquero, Paulo Sérgio Almeida, Ali Shoker","doi":"10.1145/2957319.2957374","DOIUrl":"https://doi.org/10.1145/2957319.2957374","url":null,"abstract":"State-based CRDTs allow updates on local replicas without remote synchronization. Once these updates are propagated, possible conflicts are resolved deterministically across all replicas. δ-CRDTs bring significant advantages in terms of the size of messages exchanged between replicas during normal operation. However, when a replica joins the system after a network partition, it needs to receive the updates it missed and propagate the ones performed locally. Current systems solve this by exchanging the full state bidirectionally or by storing additional metadata along the CRDT. We introduce the concept of join-decomposition for state-based CRDTs, a technique orthogonal and complementary to delta-mutation, and propose two synchronization methods that reduce the amount of information exchanged, with no need to modify current CRDT definitions.","PeriodicalId":316230,"journal":{"name":"First Workshop on Programming Models and Languages for Distributed Computing","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127931649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recent works in the context of large-scale adaptive systems, such as those for the Internet of Things (IoT) scenario, promote aggregate programming [3], a development approach for distributed systems in which one programs the aggregate of computational devices instead of individual ones. This makes the resulting behaviour highly insensitive to network size, density, and topology, and as such, intrinsically robust to failures and changes to working conditions (e.g., location of computational load, communication technology, and computational infrastructure). In this paper we are concerned with how this approach can impact mainstream software development, and hence outline a Scala-based support of aggregate programming, leveraging Scala advanced type system, DSL support, and actors mechanisms.
{"title":"Towards Aggregate Programming in Scala","authors":"Roberto Casadei, Mirko Viroli","doi":"10.1145/2957319.2957372","DOIUrl":"https://doi.org/10.1145/2957319.2957372","url":null,"abstract":"Recent works in the context of large-scale adaptive systems, such as those for the Internet of Things (IoT) scenario, promote aggregate programming [3], a development approach for distributed systems in which one programs the aggregate of computational devices instead of individual ones. This makes the resulting behaviour highly insensitive to network size, density, and topology, and as such, intrinsically robust to failures and changes to working conditions (e.g., location of computational load, communication technology, and computational infrastructure). In this paper we are concerned with how this approach can impact mainstream software development, and hence outline a Scala-based support of aggregate programming, leveraging Scala advanced type system, DSL support, and actors mechanisms.","PeriodicalId":316230,"journal":{"name":"First Workshop on Programming Models and Languages for Distributed Computing","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116651198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The consistency level of operations over replicated data is an important parameter in distributed applications. It impacts correctness, performance, and availability. It is now common to find single applications using many different consistency levels at the same time; however, current commercial frameworks do not provide high-level abstractions for specifying or reasoning about different consistency properties of an application. Research frameworks that do tend to require a substantial effort from developers to specify operation dependencies, orderings and invariants to be preserved. We propose an approach for specifying consistency properties based on the observation that correctness criteria and invariants are a property of data, not operations. Hence, it is reasonable to define the consistency properties required to enforce various data invariants on the data itself rather than on the operations. The result is a system that is simpler to describe and reason about. In this paper, we outline an abstract model of programming language constructs and a static checker for data-centric consistency control, and demonstrate this model through a simple prototype programming language implementation.
{"title":"Data-centric Consistency Policies: A Programming Model for Distributed Applications with Tunable Consistency","authors":"Nosheen Zaza, Nathaniel Nystrom","doi":"10.1145/2957319.2957377","DOIUrl":"https://doi.org/10.1145/2957319.2957377","url":null,"abstract":"The consistency level of operations over replicated data is an important parameter in distributed applications. It impacts correctness, performance, and availability. It is now common to find single applications using many different consistency levels at the same time; however, current commercial frameworks do not provide high-level abstractions for specifying or reasoning about different consistency properties of an application. Research frameworks that do tend to require a substantial effort from developers to specify operation dependencies, orderings and invariants to be preserved. We propose an approach for specifying consistency properties based on the observation that correctness criteria and invariants are a property of data, not operations. Hence, it is reasonable to define the consistency properties required to enforce various data invariants on the data itself rather than on the operations. The result is a system that is simpler to describe and reason about. In this paper, we outline an abstract model of programming language constructs and a static checker for data-centric consistency control, and demonstrate this model through a simple prototype programming language implementation.","PeriodicalId":316230,"journal":{"name":"First Workshop on Programming Models and Languages for Distributed Computing","volume":"2013 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133033201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The actor model is an established programming model for distributed applications. Combining event sourcing with the actor model allows the reconstruction of previous states of an actor. When this event sourcing approach for actors is enhanced with additional causality information, novel types of actor-based, retroactive computations are possible. A globally consistent state of all actors can be reconstructed retrospectively. Even retroactive changes of actor behavior, state, or messaging are possible, with partial recomputations and projections of changes in the past. We believe that this approach may provide beneficial features to actor-based systems, including retroactive bugfixing of applications, decoupled asynchronous global state reconstruction for recovery, simulations, and exploration of distributed applications and algorithms.
{"title":"On the Potential of Event Sourcing for Retroactive Actor-based Programming","authors":"Benjamin Erb, Gerhard Habiger, F. Hauck","doi":"10.1145/2957319.2957378","DOIUrl":"https://doi.org/10.1145/2957319.2957378","url":null,"abstract":"The actor model is an established programming model for distributed applications. Combining event sourcing with the actor model allows the reconstruction of previous states of an actor. When this event sourcing approach for actors is enhanced with additional causality information, novel types of actor-based, retroactive computations are possible. A globally consistent state of all actors can be reconstructed retrospectively. Even retroactive changes of actor behavior, state, or messaging are possible, with partial recomputations and projections of changes in the past. We believe that this approach may provide beneficial features to actor-based systems, including retroactive bugfixing of applications, decoupled asynchronous global state reconstruction for recovery, simulations, and exploration of distributed applications and algorithms.","PeriodicalId":316230,"journal":{"name":"First Workshop on Programming Models and Languages for Distributed Computing","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124128112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Distributed systems are becoming an increasingly important part of systems and applications software and it is widely accepted that writing correct distributed systems is challenging. Message-passing concurrency models are the dominant programming paradigm and, even in statically typed languages, programming frameworks typically only have limited type checking support for messages, channels, and ports or mailboxes. In this paper, we present Kola, a language-level implementation of Kompics, a component model with message-passing concurrency. Kola comes with its own compiler and some special language constructs which extend Java's type system as necessary to enforce static type checking on messages, channels, and ports. We show that Kola improves the readability of Kompics code and removes opportunities to introduce bugs, at the cost of little compile time overhead and no runtime overhead.
{"title":"Static Type Checking for the Kompics Component Model: Kola -- The Kompics Language","authors":"Lars Kroll, J. Dowling, Seif Haridi","doi":"10.1145/2957319.2957371","DOIUrl":"https://doi.org/10.1145/2957319.2957371","url":null,"abstract":"Distributed systems are becoming an increasingly important part of systems and applications software and it is widely accepted that writing correct distributed systems is challenging. Message-passing concurrency models are the dominant programming paradigm and, even in statically typed languages, programming frameworks typically only have limited type checking support for messages, channels, and ports or mailboxes. In this paper, we present Kola, a language-level implementation of Kompics, a component model with message-passing concurrency. Kola comes with its own compiler and some special language constructs which extend Java's type system as necessary to enforce static type checking on messages, channels, and ports. We show that Kola improves the readability of Kompics code and removes opportunities to introduce bugs, at the cost of little compile time overhead and no runtime overhead.","PeriodicalId":316230,"journal":{"name":"First Workshop on Programming Models and Languages for Distributed Computing","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126268508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ParalleX is an execution model tailored to exascale computing. To this aim, it employs a global shared memory and supports multi-level parallelism. In systems that mix parallelism and mutable shared memory, the definition of a memory model becomes challenging. Following the advice of Adve and Boehm (2010), we balance efficiency and simplicity by going the route of statically enforcing data-race freedom (DRF), which makes sequential consistency efficient to implement on weak memory models. In this paper, we report on a type system that ensures DRF for the core of the dataflow intermediate language used within ParalleX. The type system adapts the notion of fractional permissions to the dataflow context and provides a novel treatment of mutable references, using a combination of affine variables and fractional sums. We give an overview of the type system and demonstrate its use in some examples.
{"title":"Fractional Permissions for Race-Free Mutable References in a Dataflow Intermediate Language","authors":"M. Cimini, Jeremy G. Siek","doi":"10.1145/2957319.2957373","DOIUrl":"https://doi.org/10.1145/2957319.2957373","url":null,"abstract":"ParalleX is an execution model tailored to exascale computing. To this aim, it employs a global shared memory and supports multi-level parallelism. In systems that mix parallelism and mutable shared memory, the definition of a memory model becomes challenging. Following the advice of Adve and Boehm (2010), we balance efficiency and simplicity by going the route of statically enforcing data-race freedom (DRF), which makes sequential consistency efficient to implement on weak memory models. In this paper, we report on a type system that ensures DRF for the core of the dataflow intermediate language used within ParalleX. The type system adapts the notion of fractional permissions to the dataflow context and provides a novel treatment of mutable references, using a combination of affine variables and fractional sums. We give an overview of the type system and demonstrate its use in some examples.","PeriodicalId":316230,"journal":{"name":"First Workshop on Programming Models and Languages for Distributed Computing","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125873845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Georges Younes, Ali Shoker, Paulo Sérgio Almeida, Carlos Baquero
Pure operation-based (op-based) Conflict-free Replicated Data Types (CRDTs) are generic and very efficient as they allow for compact solutions in both sent messages and state size. Although the pure op-based model looks promising, it is still not fully understood in terms of practical implementation. In this paper, we explain the challenges faced in implementing pure op-based CRDTs in a real system: the well-known in-memory cache key-value store Redis. Our purpose of choosing Redis is to implement a multi-master replication feature, which the current system lacks. The experience demonstrates that pure op-based CRDTs can be implemented in existing systems with minor changes in the original API.
{"title":"Integration Challenges of Pure Operation-based CRDTs in Redis","authors":"Georges Younes, Ali Shoker, Paulo Sérgio Almeida, Carlos Baquero","doi":"10.1145/2957319.2957375","DOIUrl":"https://doi.org/10.1145/2957319.2957375","url":null,"abstract":"Pure operation-based (op-based) Conflict-free Replicated Data Types (CRDTs) are generic and very efficient as they allow for compact solutions in both sent messages and state size. Although the pure op-based model looks promising, it is still not fully understood in terms of practical implementation. In this paper, we explain the challenges faced in implementing pure op-based CRDTs in a real system: the well-known in-memory cache key-value store Redis. Our purpose of choosing Redis is to implement a multi-master replication feature, which the current system lacks. The experience demonstrates that pure op-based CRDTs can be implemented in existing systems with minor changes in the original API.","PeriodicalId":316230,"journal":{"name":"First Workshop on Programming Models and Languages for Distributed Computing","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124478454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"First Workshop on Programming Models and Languages for Distributed Computing","authors":"","doi":"10.1145/2957319","DOIUrl":"https://doi.org/10.1145/2957319","url":null,"abstract":"","PeriodicalId":316230,"journal":{"name":"First Workshop on Programming Models and Languages for Distributed Computing","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123096979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：