1. Fluentd v1.0 in a nutshell
March 30, 2017
Masahiro Nakagawa

2. Fluentd v0.12
• Current stable and widely used on production
• Input, Parser, Filter, Formatter, Buffer, Output plugins
• Known issues
• Event time is second unit
• No multi core support
• No Windows support
• Need to improve plugin API to support more various
use cases

3. • Development version of v1
• Latest version is v0.14.14: March 24, 2017
• Implemented New features
• New Plugin APIs
• Time with Nanosecond resolution
• ServerEngine based Supervisor
• Windows support
• Plugin Helpers & Plugin Storage
Fluentd v0.14

4. Fluentd v1
• Stable announcement for APIs / features
• No breaking API changes in v1.x
• Compatible with v0.12 and v0.14
• exclude v0 config syntax and detach_process
• Release plan
• Q2, 2017
• Need v0.14 feedback from developers and users
https://hub.docker.com/r/fluent/fluentd/

5. New Plugin APIs
• Input/Output plugin APIs w/ well-controlled lifecycle
• stop, shutdown, close, terminate
• Integrate all output plugin into Fluent::Plugin::Output
• New Buffer API for delayed commit and flexible chunking with metadata
• parallel/async "commit" operation for chunks
• For high latency case: forward’s at-least-once, issuing job, etc…
• Users can choose chunk keys by configuration for dynamic parameters
• Compatible w/ v0.12 plugins
• compatibility layer for traditional APIs
• it will be supported between v1.x versions

6. Router
buffer_chunk_limit
enqueue: exceed flush_interval
or buffer_chunk_limit
Key pattern:
- BufferedOutput
empty string or specified key
-ObjectBufferedOutput tag
-TimeSlicedOutput time slice
emit emit
Buffer
Queue
buffer_queue_limit
Output
OutputInput / Filter
Tag Time
Record Chunk
Chunk
Chunk Chunk
Chunk
key:foo
key:bar
key:baz
v0.12 buffer design

7. v0.14 buffer design

8. Buffer keys and placeholders
• Dynamic parameters for table name, object path and more
• We can embed time, tag and any field with placeholder
<match s3.**>
@type s3
aws_key_id "#{ENV['AWS_ACCESS_KEY']}"
aws_sec_key "#{ENV['AWS_SECRETA_KEY']}"
s3_bucket fluent-plugin-s3
path test/%Y/%m/${tag}/${key}/
<buffer time,tag,key>
timekey 3600
</buffer>
</match>
http://docs.fluentd.org/v0.14/articles/buffer-section for more details
time: 2017-03-30 12:00:00 +0200
tag: “test”
record: {“key”:”hello”}
- Event sample
test/2017/3/test/hello/
- Generated “path”

9. Time with nanosecond
• For sub-second systems: Elasticsearch, InfluxData, etc…
• Fluent::EventTime
• behaves as Integer for v0.12’s second unit compatibility
• has methods to get sub-second resolution
• be serialized into msgpack using Ext type
• Fluent::Engine.now now returns EventTime, not Integer
• Fluentd core can handle both of Integer and EventTime as time
• compatible with older versions and software in eco-system
(e.g., fluent-logger, Docker logging driver)

10. ServerEngine based Supervisor
• ServerEngine is a framework for building robust server
• https://github.com/treasure-data/serverengine
• Replacing supervisor process with ServerEngine
• it has SocketManager to share listening sockets
between 2 or more worker processes
• Replacing Fluentd's processing model from fork to
spawn
• to support Windows environment

11. Windows support
• Fluentd and core plugins work on Windows
• Windows service registration is also supported
• http://docs.fluentd.org/v0.14/articles/install-by-msi
• Use HTTP RPC instead of signals
• https://github.com/fluent/fluent-plugin-windows-eventlog
• We can collect windows eventlog :)

12. Symmetric multi core processing
• 2 or more workers share a configuration file
• and share listening sockets via PluginHelper
• under a supervisor process (ServerEngine)
• Multi core scalability for huge traffic
• one input plugin for a tcp port, some filters and one
(or some) output plugin
• buffer paths are managed automatically by
Fluentd. Need root_dir and @id parameters

13. Worker0
Supervisor
v0.14’s multi process feature
grep
forward
tdlog
Worker1 Worker2
grep
forward
tdlog
grep
forward
tdlog
socket

14. Configuration example
<system>
workers 2
root_dir /var/log/fluentd
</system>
<source>
@type forward
</source>
<filter pattern>
@type grep
</filter>
<match pattern>
@type tdlog
@id out_td
</match>
/var/log/fluentd/worker0/out_td/buffer/buffer.xxx.log
/var/log/fluentd/worker0/out_td/buffer/buffer.xxx.log.meta
- buf_file’s path is automatically generated
worker id
root_dir
plugin’s @id

15. TLS/Authn/Authz support for forward plugin
• secure-forward is merged into built-in forward
• TLS w/ at-least-one semantics
• Simple authentication/authorization w/o SSL
• Different points
• secure-forward uses keep-alive, but forward doesn’t
• secure-forward uses thread per connection, but
forward uses libev based IO.
http://www.fluentd.org/blog/fluentd-v0.14.12-has-been-released

16. Plugin Storage & Helpers
• Plugin Storage: new plugin type for plugins
• provides key-value storage to persistent intermediate status
• built-in plugins: in-memory, local file
• pluggable: 3rd party plugin to store data into storage
• storage-redis
• Plugin Helpers:
• collections of utility methods for plugins
• making threads, sockets, network servers, ...
• fully integrated with test drivers to run test code after setup
phase of helpers (e.g. test started after created threads)

17. server helper: before
def start
@loop = Coolio::Loop.new
@handler = Coolio::TCPServer.new(@bind, @port, SocketUtil::TcpHandler, log,
@delimiter, method(:on_message))
@loop.attach(@handler)
@thread = Thread.new(&method(:run))
end
def shutdown
@loop.watchers.each { |w| w.detach }
@loop.stop
@handler.close
@thread.join
end
def run
@loop.run(@blocking_timeout)
rescue => e
log.error "unexpected error", error: e
log.error_backtrace
end
def on_message(msg, addr)
# body
end

18. server helper: after
def start
server_create(:foo_server, @port, bind: @bind) do |data, conn|
# body
end
end

19. v0.12 plugins
ParserInput Buffer Output FormatterFilter
“output-ish”“input-ish”

20. v0.14 plugins
ParserInput Buffer Output FormatterFilter
“output-ish”“input-ish”
Storage
Helper

21. TODO list for v1
• <worker N> directive to separate plugins
• https://github.com/fluent/fluentd/pull/1507
• Counter API to store metrics between processes
• https://github.com/fluent/fluentd/tree/counter-api
• Migrate more plugin into v0.14 API
• Fix regressions and bugs
• Write docuemnt: design, plugin, operation, etc…

22. <worker N> directive
• To execute plugins under one process
• Good for non-multiprocess supported plugins like in_tail
<system>
workers 4
</system>
<source>
@type forward
</source>
<match pattern>
@type mongo
</match>
<worker 0>
<source>
@type in_tail
</source>
<match pattern>
@type s3
</match>
</worker>
in_tail/out_s3 works under worker 0
in_forward/out_mongo works
under multiprocess environment with
worker 1, worker 2, and worker 3

23. Treasure Agent 3.0 (td-agent 3)
• fluentd v0.14, Ruby 2.4, and latest core components
• Environments
• Add msi Windows package
• Remove CentOS 5, Ubuntu 10.04 support
• Beta packages have beed released
• http://docs.fluentd.org/v0.14/categories/installation
• beta will be removed after v0.14 becomes stable :)