Explains how Erlang On Xen can transform cloud computing in future

1. Erlang on Xen:
the four themes
erlangonxen.org
kiev::fprog 2013
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2. The four themes
1. “Truly elastic services”
2. “Ephemeral servers”
3. “Autonomous clouds”
4. “Data-local computations”
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3. Erlang on Xen 101
• Erlang runtime, runs over bare Xen w/o OS
• Built from scratch, not a “port”
• Conceived in 2009
• Highly-compatible with Erlang/OTP
• Optimised for low startup latency
• Not an open source (yet)
• The public build service is free
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4. 1. “Truly elastic services”
● Erlang on Xen instances (VMs) start to execute
Erlang code 4-5ms after the launch
● Sustainable spawning rate = 10 VMs/sec
● See rush.erlangonxen.org
● Let the application decide how many nodes are
needed
● Spawning a node mimics spawning an Erlang
process
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5. 2. “Ephemeral servers”
● Zero-footprint clouds – waiting services do not
exist/consume resources
● Weave a computing environment and lease
resources on demand only
● Startup latency for Erlang on Xen fits a
“processing window”
● A single physical node may host thousands (or
millions) of ephemeral servers
● Better granularity and easier development
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6. Demo: Zerg
zerg.erlangonxen.org — instance-per-request proof of concept
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7. 3. “Autonomous clouds”
● OS-less instances are generally smaller, short-
lived and easy to migrate
● Applications can manage themselves
● No Chef/Puppet anymore
● A cloud infrastructure can become fully
autonomous
● Applications and data stay legally under the
user’s control
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8. 4. “Data-local computations”
● Erlang on Xen instances are building blocks of
future databases
● “Scanning” queries should spawn many
processing instances close to data
● ...
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9. Demo: A 1000-node cluster
● Each node in its turn
– Waits for a message to arrive (receive)
– Spawns a new node
– Waits for the new node to become available
– Runs a local ring of 7,777 processes
– Mounts a share on the new node (9p)
– Writes the message to /peer/mailbox – the write
gets converted into Erlang message passing
– Waits for 3 seconds
– Destroys itself
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10. Demo: A 1000-node cluster
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11. 7 commandments of a NewSoftware
1. Do not assume the presence of OS underneath
2. Software must be oblivious to boundaries of
physical nodes
3. All services share the same auto-scalable
infrastructure
4. Run computations near the data they process
5. Child nodes get configuration from the parent only
6. Avoid “administration” at all costs
7. SMP is abomination of cloud computing
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12. Thank you. Questions?
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