Building Applications with Distributed Erlang

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BUILDING APPLICATIONS with DISTRIBUTED ERLANG cmeik the adventures of hash(<<“author”>>, <<“Christopher Meiklejohn”>>)

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who am i CMEIK

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who am i CMEIK

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who am i CMEIK distributed systems engineer basho technologies

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who am i CMEIK distributed systems engineer basho technologies researcher with the syncfree project

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what is THE AGENDA

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what is THE AGENDA (novice) 1. what is distributed erlang?

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what is THE AGENDA (novice) 1. what is distributed erlang? (erlanger) 2. where do i go from here?

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what is DISTRIBUTED ERLANG

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what is DISTRIBUTED ERLANG EXTENSION TO HELP BUILD DISTRIBUTED SYSTEMS

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what is DISTRIBUTED ERLANG EXTENSION TO HELP BUILD DISTRIBUTED SYSTEMS

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what are the goals of a DISTRIBUTED SYSTEM

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what are the goals of a DISTRIBUTED SYSTEM “A distributed system is a software system in which components located on networked computers communicate and coordinate their actions by passing messages. The components interact with each other in order to achieve a common goal. Three significant characteristics of distributed systems are: concurrency of components, lack of a global clock, and independent failure of components.” Wikipedia, “Distributed Computing”

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what are some examples of a DISTRIBUTED SYSTEM

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what are some examples of a DISTRIBUTED SYSTEM distributed databases, riak, cassandra, etc.

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what are some examples of a DISTRIBUTED SYSTEM distributed databases, riak, cassandra, etc. master/slave in sql, multi-partition txns

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what are some examples of a DISTRIBUTED SYSTEM distributed databases, riak, cassandra, etc. master/slave in sql, multi-partition txns web services via rest, soap, etc.

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what are some examples of a DISTRIBUTED SYSTEM distributed databases, riak, cassandra, etc. master/slave in sql, multi-partition txns web services via rest, soap, etc. mobile clients, internet of things

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why are distributed systems HARD L. Peter Deutsch, “Fallacies of Distributed Computing”

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why are distributed systems HARD the network is reliable L. Peter Deutsch, “Fallacies of Distributed Computing”

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why are distributed systems HARD the network is reliable latency is zero L. Peter Deutsch, “Fallacies of Distributed Computing”

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why are distributed systems HARD the network is reliable latency is zero bandwidth is infinite L. Peter Deutsch, “Fallacies of Distributed Computing”

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why are distributed systems HARD the network is reliable latency is zero bandwidth is infinite the network is secure L. Peter Deutsch, “Fallacies of Distributed Computing”

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why are distributed systems HARD the network is reliable latency is zero bandwidth is infinite the network is secure topology doesn’t change L. Peter Deutsch, “Fallacies of Distributed Computing”

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why are distributed systems HARD the network is reliable latency is zero bandwidth is infinite the network is secure topology doesn’t change there is one administrator L. Peter Deutsch, “Fallacies of Distributed Computing”

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why are distributed systems HARD the network is reliable latency is zero bandwidth is infinite the network is secure topology doesn’t change there is one administrator transport cost is zero L. Peter Deutsch, “Fallacies of Distributed Computing”

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why are distributed systems HARD the network is reliable latency is zero bandwidth is infinite the network is secure topology doesn’t change there is one administrator transport cost is zero the network is homogeneous L. Peter Deutsch, “Fallacies of Distributed Computing”

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what is DISTRIBUTED ERLANG

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what is DISTRIBUTED ERLANG 1 3 2 4 5

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what is DISTRIBUTED ERLANG 1 3 2 4 5 transparent • message passing • links • monitors transitive connections (except hidden nodes) access control via cookies

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what is DISTRIBUTED ERLANG 1 3 2 4 5 transparent • message passing • links • monitors transitive connections (except hidden nodes) access control via cookies 6

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what is DISTRIBUTED ERLANG 1 3 2 4 5 transparent • message passing • links • monitors transitive connections (except hidden nodes) access control via cookies 6

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what is DISTRIBUTED ERLANG 1 3 2 4 5 transparent • message passing • links • monitors transitive connections (except hidden nodes) access control via cookies 6

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what is DISTRIBUTED ERLANG

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what is DISTRIBUTED ERLANG 1 2

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what is DISTRIBUTED ERLANG 1 spawn functions on other nodes 2 p1 p2

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what is DISTRIBUTED ERLANG 1 spawn functions on other nodes 2 p1 p2 monitor or link on other nodes

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what is DISTRIBUTED ERLANG 1 spawn functions on other nodes 2 p1 p2 monitor or link on other nodes 1 2 p1 p2

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what is DISTRIBUTED ERLANG 1 spawn functions on other nodes 2 p1 p2 monitor or link on other nodes 1 2 p1

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what distributed erlang gets RIGHT

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what distributed erlang gets RIGHT assumes unreliable asynchronous message passing

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what libraries come with DISTRIBUTED ERLANG

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what libraries come with DISTRIBUTED ERLANG global - global name registration and locking

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what libraries come with DISTRIBUTED ERLANG global - global name registration and locking pg2 - process group registry

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what libraries come with DISTRIBUTED ERLANG global - global name registration and locking pg2 - process group registry mnesia - distributed transactions

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what libraries come with DISTRIBUTED ERLANG global - global name registration and locking pg2 - process group registry mnesia - distributed transactions net_kernel - erlang distributed networking kernel

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what is GLOBAL

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what is GLOBAL global name registration and locking service

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what is GLOBAL global name registration and locking service shared state, replicated locally

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what is GLOBAL global name registration and locking service shared state, replicated locally races under network partitions

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what is GLOBAL global name registration and locking service shared state, replicated locally races under network partitions provides ad-hoc resolution hook

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what is PG2

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what is PG2 distributed process group registry

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what is PG2 distributed process group registry usually used for work partitioning

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what is PG2 distributed process group registry usually used for work partitioning races under network partitions

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what is PG2 distributed process group registry usually used for work partitioning races under network partitions can lose values under network partitions

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what is PG2 distributed process group registry usually used for work partitioning races under network partitions can lose values under network partitions originally isis inspired, pg descendent

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what is MNESIA

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transactional database in erlang what is MNESIA

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transactional database in erlang implemented using replicated ets tables what is MNESIA

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transactional database in erlang implemented using replicated ets tables global transactions are *expensive* what is MNESIA

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transactional database in erlang implemented using replicated ets tables global transactions are *expensive* network partitions can cause values to be lost what is MNESIA

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what is NET_KERNEL

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maintenance of network in distributed erlang what is NET_KERNEL

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maintenance of network in distributed erlang responsible for detecting failures what is NET_KERNEL

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maintenance of network in distributed erlang responsible for detecting failures dropped tcp connections, network partitions what is NET_KERNEL

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maintenance of network in distributed erlang responsible for detecting failures dropped tcp connections, network partitions poor mechanism for cluster management what is NET_KERNEL

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what is RPC

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remote procedure call services what is RPC

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remote procedure call services serialized execution of requests what is RPC

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remote procedure call services serialized execution of requests call to a single node, or multi call what is RPC

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remote procedure call services serialized execution of requests call to a single node, or multi call synchronous programming pattern what is RPC

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what are the ANTI-PATTERNS*

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what are the ANTI-PATTERNS* utilizing shared state

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what are the ANTI-PATTERNS* utilizing shared state reliance on physical time

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what are the ANTI-PATTERNS* utilizing shared state reliance on physical time using predesignated masters

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what are the ANTI-PATTERNS* utilizing shared state reliance on physical time using predesignated masters treating the network as synchronous

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what are the ANTI-PATTERNS* utilizing shared state reliance on physical time using predesignated masters treating the network as synchronous * also: distributed objects, guaranteed delivery mechanisms, distributed serializable transactions, etc.

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unfortunately these mechanisms are NAIVE so, what can do we and what have we LEARNED

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what about CLUSTER MEMBERSHIP

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what about CLUSTER MEMBERSHIP 1 3 2 4

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what about CLUSTER MEMBERSHIP fixed membership, a priori 1 3 2 4

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what about CLUSTER MEMBERSHIP fixed membership, a priori don’t tie to net_kernel, net_ticktime 1 3 2 4

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what about CLUSTER MEMBERSHIP fixed membership, a priori don’t tie to net_kernel, net_ticktime store information locally, gossip 1 3 2 4

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what about CLUSTER MEMBERSHIP fixed membership, a priori don’t tie to net_kernel, net_ticktime store information locally, gossip hyparview, plumtree, thicket 1 3 2 4

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what about FAILURE DETECTION 1 3 2 4

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what about FAILURE DETECTION detection of delays vs. failed nodes 1 3 2 4

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what about FAILURE DETECTION detection of delays vs. failed nodes net_kernel, net_ticktime 1 3 2 4

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what about FAILURE DETECTION detection of delays vs. failed nodes net_kernel, net_ticktime the φ accrual failure detector 1 3 2 4

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what about FAILURE DETECTION detection of delays vs. failed nodes net_kernel, net_ticktime the φ accrual failure detector swim: membership and failure detector 1 3 2 4

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what about VALUE DIVERGENCE

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what about VALUE DIVERGENCE replicated data can diverge 1 1

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what about VALUE DIVERGENCE replicated data can diverge 1 3 2 1

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what about VALUE DIVERGENCE replicated data can diverge 1 3 2 1 ?

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what about VALUE DIVERGENCE replicated data can diverge identify concurrency 1 3 2 1 ?

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what about VALUE DIVERGENCE replicated data can diverge lamport clock, vector clocks, version vectors, wall clock identify concurrency 1 3 2 1 ?

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what about VALUE DIVERGENCE replicated data can diverge lamport clock, vector clocks, version vectors, wall clock identify concurrency how to resolve? lww vs. siblings vs. crdt 1 3 2 1 ?

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what about DISTRIBUTION BUFFERS

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what about DISTRIBUTION BUFFERS 1 2 p1 p3 p2

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what about DISTRIBUTION BUFFERS 1 2 p1 p3 p2

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what about DISTRIBUTION BUFFERS 1 2 p1 p3 p2 large objects can cause head-of-line blocking

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what about DISTRIBUTION BUFFERS 1 2 p1 p3 p2 large objects can cause head-of-line blocking move objects to tcp sockets

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what about DISTRIBUTION BUFFERS 1 2 p1 p3 p2 large objects can cause head-of-line blocking move objects to tcp sockets increase distribution port buffer size

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what about DISTRIBUTION BUFFERS 1 2 p1 p3 p2 large objects can cause head-of-line blocking move objects to tcp sockets increase distribution port buffer size beware unbounded queues

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what about LEADER ELECTION

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what about LEADER ELECTION 1 2 3 4

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what about LEADER ELECTION gen_leader assumes fixed topology 1 2 3 4

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what about LEADER ELECTION gen_leader assumes fixed topology use paxos or raft 1 2 3 4

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what about LEADER ELECTION gen_leader assumes fixed topology use paxos or raft gen_leader known to deadlock 1 2 3 4

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what about MESSAGE FORMATS

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what about MESSAGE FORMATS v1 v2

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what about MESSAGE FORMATS mixed version clusters reality in large systems v1 v2

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what about MESSAGE FORMATS mixed version clusters reality in large systems keep formats compatible v1 v2

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what about MESSAGE FORMATS mixed version clusters reality in large systems keep formats compatible upgrade to new format v1 v2

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what about MESSAGE DELIVERY

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what about MESSAGE DELIVERY message delivery not guaranteed with failures

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what about MESSAGE DELIVERY message delivery not guaranteed with failures 1 2

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what about MESSAGE DELIVERY message delivery not guaranteed with failures 1 2 1 2 3 4

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what about MESSAGE DELIVERY message delivery not guaranteed with failures 1 2 1 1 2 2 3 1 4 3 4

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what can we take away from this DISCUSSION

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what are the LESSONS

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distributed erlang gets you part of the way but, you still have to understand the problems and the tradeoffs what are the LESSONS

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distributed erlang gets you part of the way but, you still have to understand the problems and the tradeoffs what are the LESSONS http://christophermeiklejohn.com/distributed/systems/ 2013/07/12/readings-in-distributed-systems.html

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what are some useful ERLANG LIBRARIES

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what are some useful ERLANG LIBRARIES riak_core: distributed systems toolkit https://github.com/basho/riak_core

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what are some useful ERLANG LIBRARIES riak_core: distributed systems toolkit https://github.com/basho/riak_core riak_ensemble: generic multi-paxos framework https://github.com/basho/riak_ensemble

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what are some useful ERLANG LIBRARIES riak_core: distributed systems toolkit https://github.com/basho/riak_core riak_ensemble: generic multi-paxos framework https://github.com/basho/riak_ensemble riak_dt: conflict-free replicated data types https://github.com/basho/riak_dt

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what are some useful RESEARCH PROJECTS

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what are some useful RESEARCH PROJECTS syncfree: large-scale computation on erlang https://github.com/syncfree

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what are some useful RESEARCH PROJECTS syncfree: large-scale computation on erlang https://github.com/syncfree release: large-scale erlang deployments https://github.com/release-project/

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what are some useful RESEARCH PROJECTS syncfree: large-scale computation on erlang https://github.com/syncfree release: large-scale erlang deployments https://github.com/release-project/ paraphrase: parallel computation https://github.com/paraphrase

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what are some PUBLICATIONS

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what are some PUBLICATIONS

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what are some PUBLICATIONS

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what are some PUBLICATIONS

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what are some PUBLICATIONS

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what are some PUBLICATIONS

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what are some PUBLICATIONS pid reuse unreliable failure detectors unreliable delivery of messages …and more!