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Streams

Page for release 1.8.1. See this page for: release 1.8.2, release 1.8.4

As explained below, Redcurrant is client centric. This means that the most important part of communication happens between the client and Redcurrant services, not between services.

Inter process communication

The following table describes streams and types between Redcurrant processes.

From process To process Type Usage
Meta0 Zookeeper TCP Master election mechanism
Meta0 gridagent UNIX Statistics management
Meta1 Zookeeper TCP Master election mechanism
Meta1 gridagent UNIX Statistics management
Meta2 Zookeeper TCP Master election mechanism
Meta2 gridagent UNIX Statistics management
gridagent conscience TCP Statistics management
sqlx Zookeeper TCP Master election mechanism
sqlx gridagent UNIX Statistics management
rawx gridagent UNIX Statistics management

Client Server communication

Connexion diagram for a simple PUT operation in a container

  1. Client - Conscience. Find meta0
  2. Client - meta0 : find meta1 for the prefix of the container
  3. Client - meta1 : find which meta2 services manages this container
  4. Client - meta2 : find available RAWX to store content with the given storage policy
  5. Client - RAWX : upload chunks
  6. Client - meta2 : validate chunk location

Some response can be put in cache for performance reason


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