Collage  1.1.2
High-performance C++ library for developing object-oriented distributed applications.
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Release Notes


Welcome to Collage, a high-performance C++ library for developing object-oriented distributed applications.

Collage 1.1 is a preview release for an upcoming stable 1.2 release which has over eight years of development and decades of experience into a high-performance and mature C++ library. It is intended for all C++ developers creating distributed applications with high-level abstractions. Collage 1.1 can be retrieved by downloading the source code or one of the precompiled packages.


Collage provides different levels of abstraction to facilitate the development distributed applications:

  • Network Connections: stream-oriented point-to-point and reliable multicast connections for TCP/IP, SDP, InfiniBand RDMA, UDT, events, named and anonymous pipes, memory buffers and reliable multicast over UDP.
  • Peer-to-Peer Messaging: Endian-safe node-to-node message communication with thread-aware message dispatch.
  • Synchronization: Distributed barriers and synchronous messaging.
  • Object data distribution: high-performance, object-oriented, versioned data distribution for C++ objects based on delta serialization.

New in this release

Collage 1.1 contains the following features, enhancements, bug fixes and documentation changes over the Collage release:

New Features

  • 54: Enable serialization of std::string Arrays


  • 37: Make CommandQueue maximum size configurable
  • 55: Robustness for late join
  • 69: Refactor Barrier API for robustness, deprecate old API


  • 27: Add LocalNode::syncObject
  • 28: BufferCache::compact too expensive
  • 38: Make ConnectionSet processing round-robin on Unix


  • No new tools


The following documentation has been added or substantially improved since the last release:

  • gives more initial information, build instructions and links to released versions
  • API documentation of the public Collage API

Bug Fixes

Collage 1.1 includes various bugfixes over the Collage release, including the following:

  • 16: RSP Interface not bound on Linux
  • 29: Change managers may access dangling objects
  • 32: Default port is priviledged for high UIDs
  • 34: ICommand behaves incorrect once all data is consumed
  • 50: Use correct master node for mapping objects
  • 52: RSP: Protocol bug for very late and early packet delivery.
  • 71: BufferCache race may lead to segmentation fault
  • 79: Node::connect race condition
  • 82: Barrier races and deadlocks with sync()
  • 88: LocalNode::handleData() asserts handling non-pending receive
  • 112: Fix racy connection handshake
  • 113: De-race EventConnection::close to fix Travis

Known Bugs

The following bugs were known at release time. Please file a Bug Report if you find any other issue with this release.

  • 57: Windows: Larger number of concurrent receives causes intermittent blocking
  • 15: RDMAConnection not endian-safe
  • 14: coNetperf server occasionally crashes on client disconnect
  • 2: Multiple dispatcher inheritance not working with xlC


Collage is a cross-platform library, designed to run on any modern operating system, including all Unix variants and the Windows operating system. Collage uses CMake and Buildyard to create a platform-specific build environment. The following platforms and build environments are tested for version 1.1:

  • Linux: Ubuntu 14.04, RHEL 6.5 (Makefile, i386, x64)
  • Windows: 7 (Visual Studio 2008, i386, x64)
  • Mac OS X: 10.8 (Makefile, XCode, i386, x64)

The Equalizer Programming and User Guide covers the basics of Collage programming. The API documentation can be found on github.

As with any open source project, the available source code, in particular the shipped tools provide a reference for developing or porting applications.

Technical questions can be posted to the eq-dev Mailing List, or directly to

Commercial support, custom software development and porting services are available from Eyescale. Please contact for further information.