transmission/news/news-4.0.0.md

12 KiB

Transmission 4.0.0

Highlights

This is a major release, both in numbering and in effort! It's been in active development for over a year and has a huge list of changes -- over a thousand commits -- since Transmission 3.00. Some of the highlights include:

Resource Efficiency

  • The code has been extensively profiled and improved to fix inefficient code and memory use. For example, a stress test of starting transmission-daemon with 25,000 torrents is almost entirely IO-bound, using 50% fewer CPU cycles and 70% fewer memory allocations than Transmission 3.00.

  • The remote control GUIs (transmission-qt and transmission-web) now use the RPC API "table" mode, resulting in smaller payloads / less bandwidth use.

  • RPC payloads are now compressed using libdeflate, a "heavily optimized [library that is] significantly faster than the zlib library."

Community

  • The project is much more responsive to bug reports and code submissions than it has been in the past.
  • There is a new group of volunteer contributors who are working on Transmission!
  • Transmission 4.0.0 includes over 350 new community commits (see the Thank You section below and in the previous 4.0.0 betas) since 3.00 and welcomes new contributors.
  • Documentation has been moved into the transmission/transmission so that contributors can submit PRs to improve it.

Code Modernization

  • The entire codebase has been migrated from C to C++. In the process, we've removed thousands of lines of custom code and used standard C++ tools instead. The core's code has shrunk by 18%. The core codebase has been extensively refactored to be more testable and maintainable.
  • The GTK client has been ported to gtkmm.
  • The Web client has been rewritten in modern JavaScript and no longer uses jQuery. The entire gzipped bundle is now 68K.
  • The unit tests have been expanded and ported to Google Test. Clang sanitizer builds are run during CI.
  • The core library is now fuzz tested.
  • Transmission now uses Sonarcloud, Coverity, LGTM, and clang-tidy static analysis on new code. Several hundred code warnings have been fixed compared to Transmission 3.00.

New Features

  • Support for using BitTorrent v2 torrents and hybrid torrents. (Support for creating v2 and hybrid torrents is slated for an upcoming release.)
  • Users can now set "default" trackers that can be used to announce all public torrents.
  • Newly-added seeds can start immediately and verify pieces on demand, instead of needing a full verify before seeding can begin. (#2626)
  • Added an option to omit potentially-identifying information (e.g. User-Agent and date created) when creating new torrents. (#3452)
  • The Web client has been rewritten and now supports mobile use.
  • When creating new torrents, users can now specify the piece size. (#3768, #3145, #2805)
  • IPv6 blocklists are now supported. (#3835)
  • Beginning with 4.0.0-beta.1, Transmission releases now use semver versioning.
  • Dozens of other new features -- too many to list here! We've been working on this for a year!

What's New Since 4.0.0-beta.3

libtransmission (All Platforms)

  • Added a new setting, torrent-added-verify-mode, to force-verify added torrents. (#4611)
  • Improved handling of webseed servers that do not support Range requests or 206 Partial Content. (#4601)
  • Improved handling of webseed servers that return a content-encoding that was not requested. (#4609)
  • Fixed 4.0.0-beta.3 potential socket leak. (#4616)
  • Fixed 4.0.0-beta.3 regression that failed to detect largefile build flags on 32bit systems. (#4627)
  • Fixed 4.0.0-beta.1 UI bug when removing a tracker from the announce list. (#4635)
  • Improved error handling when receiving corrupt piece data from peers. (#4665)
  • Fixed 4.0.0-beta.1 FTBFS error on CentOS 7. (#4673, #4675)
  • Made small performance improvements in libtransmission. (#4577, #4679)
  • Dropped libiconv dependency in libtransmission. (#4565)
  • Updated 403 RPC error message. (#4567)
  • Bumped libdeflate snapshot to 1.17. (#4596)

macOS Client

  • Fixed two Help menus in macOS. (#4500)
  • Fixed bug that caused magnet links to always be paused when added. (#4528)
  • Fixed 4.0.0-beta.1 regression that broke the Piece View "blinking" when a piece completes. (#4587)
  • Ensured that the preferences window is centered the first time it is shown. (#4659)
  • Fixed 4.0.0-beta.1 regression that incorrectly handled corrupt blocklists. (#4705)
  • Increased the font size in the main window's torrent list. (#4557)
  • Fixed libpsl dependency build issue on macOS. (#4642)

Qt Client

  • Made display order of speed limits consistent between Properties, Details dialogs. (#4677)

GTK Client

  • Fixed 4.0.0-beta.1 regression making it impossible to close "Set location" dialog (GTK 3 only). (#4625)
  • Fixed 4.0.0-beta.2 regression leading to crash during progress bars rendering on some systems. (#4688)

Web Client

  • Fixed 4.0.0-beta.1 potential crash when detecting mime-types. (#4569)
  • Fixed 4.0.0-beta.1 regression that broke file priority buttons in the web client. (#4610)

Daemon

  • Fixed stderr logging issue when running as a systemd unit. (#4612)

transmission-remote

  • Fixed 4.0.0-beta.1 regression when displaying session info. (#4624)
  • Fixed 4.0.0-beta.1 regression when displaying tracker info. (#4633)

Thank You!

Last but certainly not least, a big Thank You to these people who contributed to this release:

Contributions to libtransmission (All Platforms):

Contributions to macOS Client:

Contributions to Qt Client:

Contributions to Web Client:

Contributions to Daemon:

Contributions to transmission-remote:

Contributions to Everything Else: