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Apache DistributedLog graduated from Apache Incubator and is a sub-project of Apache BookKeeper now!
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        A <strong>high-throughput</strong>, <strong>low-latency</strong> replicated log service, offering <strong>durability</strong>, <strong>replication</strong> and <strong>strong consistency</strong> as essentials for building reliable <strong>real-time</strong> applications.
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            High Performance
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DL is able to provide <strong>milliseconds</strong> latency on <strong>durable</strong> writes with a large number
of concurrent logs, and handle high volume reads and writes per second from
thousands of clients.
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            Durable and Consistent 
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Messages are persisted on disk and replicated to store multiple copies to
prevent data loss. They are guaranteed to be consistent among writers and
readers in terms of <strong>strict ordering</strong>.
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            Efficient Fan-in and Fan-out
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DL provides an efficient service layer that is optimized for running in a multi-
tenant datacenter environment such as <i>Mesos</i> or <i>Yarn</i>. The service layer is able
to support large scale writes (fan-in) and reads (fan-out).
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            Various Workloads
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DL supports various workloads from <strong>latency-sensitive</strong> online transaction
processing (OLTP) applications (e.g. WAL for distributed database and in-memory
replicated state machines), real-time stream ingestion and computing, to
analytical processing.
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            Multi Tenant
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To support a large number of logs for multi-tenants, DL is designed for I/O
isolation in real-world workloads.
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            Layered Architecture
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DL has a modern layered architecture design, which separates the <strong>stateless
service tier</strong> from the <strong>stateful storage tier</strong>. To support large scale writes (fan-
in) and reads (fan-out), DL allows scaling storage independent of scaling CPU
and memory.
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    <h3>Blog</h3>
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Apache DistributedLog is available under [Apache License, version 2.0](http://www.apache.org/licenses/LICENSE-2.0).