Difference between revisions of "Micro-threading"
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==Implementation== | ==Implementation== | ||
− | * [http://svn.zdechov.net | + | * [http://svn.zdechov.net/PascalClassLibrary/MicroThreading/ MicroThreading] - Lazarus package, functional yet not finished, not multi-platform, need patching FPC |
==External links== | ==External links== |
Revision as of 21:19, 21 December 2018
Introduction
There are some situations where applications need to execute lots of asynchronous concurrent operations. OS-level threads could be used for this purpose, but an application can create only a limited count of threads. As for CPU utilization there is no significant performance gain if more threads are created than physical cores available on a CPU. In fact threads could be used for parallel processing on a multicore CPU and for writing more readable code. OS-level threads should be used mainly used for parallelism and better CPU utilization. If a programmer needs to write code which will be called asynchronously, then OS-level threads will be rather expensive in perspective of system resources.
CPU context switching methods
- Cooperative (use of explicit Yield call)
- Preemptive (periodic timer based)
- Combined
Objectives
- Unlimited number of instances (limited by available memory)
- Fast switching, creation, destruction
- Automatic thread pool management by physical CPU core count
- Ability to run in main loop only (without TThread instances)
- Provide own synchronization tools (Yield, Sleep, CriticalSection, Semaphore, Mutex, WaitForMultipleObjects, Queues, Synchronize, ...)
- Priority control
- Support for view list of all microthreads
Implementation
- MicroThreading - Lazarus package, functional yet not finished, not multi-platform, need patching FPC