OmniThreadLibrary 3.09

OmniThreadLibrary 3.09 has just been released! This is a big release with some new functionality and many bug fixes.

It is available via Git or as a ZIP archive.

What is OmniThreadLibrary?

OmniThreadLibrary is simple to use threading library for Delphi. It's main "selling" points (besides the price, of course are power, simplicity, and openess. With just few lines of code, you can set up multiple threads, send messages between them, process Windows messages and more. OmniThreadLibrary doesn't limit you in any way - if it is not powerfull enough for you, you can ignore any part of its "smartness" and replace it with your own code. If you don't like working with threads - no problem! You can use high-level primitives like parallel for, futures and pipelines to introduce parallelism into your application.

OmniThreadLibrary is an open source project. It lives in the Google Code and is licensed under the BSD license.

At the moment, OmniThreadLibrary supports Delphi 2007, 2009, 2010, XE, XE2, XE3, XE4, XE5, XE6, XE7, XE8, 10 Seattle, 10.1 Berlin, 10.2 Tokyo,  10.3 Rio, 10.4 Sydney, 11 Alexandria, 12 Athens, and 13 Florence on the Win32 and Win64 platforms. 

There are no plans to support older Delphi compilers. XE2+ support is limited to Windows targets. Firemonkey is currently not supported.

For cross-platform development (Linux, macOS, Android, iOS) and for new features that are not (yet) available here, see OmniThreadLibrary-NG, the next generation of the library.

Where can I get more information?

Home page: http://www.omnithreadlibrary.com/

Support: http://www.omnithreadlibrary.com/support/

Downloads: http://www.omnithreadlibrary.com/download/

Repository: https://github.com/gabr42/OmniThreadLibrary

Issue tracker: https://github.com/gabr42/OmniThreadLibrary/issues

Documentation: http://www.omnithreadlibrary.com/documentation/

Changes since version 3.08

Important changes:

• OmniThreadLibrary is now Windows-only. All POSIX/non-Windows support (mobile, Linux, OSX, Android, iOS) was removed, together with the OTL_MobileSupport define; the non-Windows code path was never functional in this repository. Cross-platform support lives in the OmniThreadLibrary-NG project.
• OTL_OLDCPU is no longer defined by default in 32-bit builds (issue #118).
• The queues now use the SSE2 atomic move, as OmniThreadLibrary-NG does. On a CPU without SSE2, define OTL_OLDCPU in the project options; otherwise OtlContainers raises an exception at startup that tells you to do so.
• Exceptions raised in the body of Parallel.For and Parallel.ForEach are now collected and raised in the calling thread as EJoinException (not when NoWait is used), the same way Parallel.Join works (issue #57). Previously they hung ForEach and were silently lost in For.
• TLightweightMREWEx is stricter: BeginRead while owning the write lock raises unless AllowReadInsideWrite is set (before first use), and BeginWrite while holding a read lock raises (it used to deadlock).

New features:

• Parallel.For supports Int64 ranges and loop bodies (issue #180).
• IOmniBlockingCollection.DeThrottle / IsThrottling and IOmniPipeline.DeThrottle switch throttling off at run time and wake up blocked writers (issue #61).
• CSP-style abstractions backported from OmniThreadLibrary-NG (Delphi XE and newer): Parallel.Channel<T>, Parallel.Select (with SelectCase.Receive<T> and Default), Parallel.Merge<T>, Parallel.Race<T> / TryRace<T> and ESelectTimeout.
• TLightweightMREWEx has recursion-safe read locks (nested BeginRead can no longer deadlock behind a pending writer) and the new AllowReadInsideWrite property.
• C++Builder (Win32 and Win64): the generated headers for DSiWin32, GpLists, OtlCommon, OtlSync and OtlParallel compile (issue #72). The Delphi API does not change.
• DSiWin32: define DSiNoTimerResolution to prevent the library from raising the Windows timer resolution to 1 ms (issue #68).
• Delphinus/DPM packages updated for Delphi 12 and 13.
• Added the otl-reference skill for Claude Code (docs/claude-skill).

Bug fixes:

• Fixed numerous bugs found by static analysis and code review in OtlContainers, OtlCommon, OtlComm, OtlHooks, OtlParallel, OtlSync, OtlTaskControl, OtlThreadPool, OtlDataManager and OtlSync.Utils (lost observer notifications, ring-buffer full detection, races and deadlocks in OtlSync, thread-safe lazy initialization of the global pools, pipeline closure capture, ...). See history.txt for details.
• TWaitFor with 64 or more handles crashed the process (issue #227, PR #229 by Oleksiy Penkov).
• ReceiveWait/SendWait could lose or duplicate a message and hang thread pool workers or Parallel.For (issue #228, PR #230 by Oleksiy Penkov).
• Receive/ReceiveWait swallowed OTL's internal messages (issue #50).
• Unobserved conflicted with MonitorWith (issue #154).
• Tasks created in non-main threads were never released, causing memory growth with nested Parallel.Async, Pipeline and For (issues #78, #69, #152).
• Data race on the task TerminatedEvent handle (issue #216).
• AV when destroying a non-empty TOmniValueQueue (issue #201).
• TOmniBaseQueue alignment assertions with some memory managers (issue #177).
• Parallel.ForEach<TOmniValue> and ForEach over object enumerables failed (issues #49, #176).
• NoWait ForEach over a blocking collection could hang at exit.
• Parallel.For/ForEach waited forever when a task could not be started (issue #213); TOmniEventMonitor.Destroy raised an AV when its window could not be allocated (issue #24).
• A worker raised ERROR_NOT_ENOUGH_QUOTA when the monitoring thread was stalled (issue #182).
• DSiWin32: crashes at finalization (issue #224).
• Send blocked on a full channel is woken up by Close.