1 / 4

UCoM Software Architecture

UCoM Software Architecture. http://ucom. UCoM Programming Model. The Problem Multi-threaded code is difficult to write and debug. Our goal is to reduce subtle concurrency bugs and race conditions Our Approach

kyoko
Download Presentation

UCoM Software Architecture

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. UCoM Software Architecture http://ucom

  2. UCoM Programming Model The Problem • Multi-threaded code is difficult to write and debug. Our goal is to reduce subtle concurrency bugs and race conditions Our Approach • Program written in terms of tasks that are not pre-emptively scheduled, i.e., cooperative multi-tasking • No mutual exclusion work by programmer • Only one task active at any time

  3. What are Tasks in UCoM • Sequence of operations possibly containing I/O operations (e.g., network receives) • Whole address space is “locked” for the task until it relinquishes control: Piecewise Serial • “Lock” released automatically when task performs I/O • Programmer must validate state after “reacquiring” lock; similar to high-performance servers • Like event-driven programming but without inconvenience of using continuation-passing style in C/C++/C#.

  4. Support for UCoM Tasks Threads needed to achieve task abstraction: • Scheduler thread for controlling execution • One or more threads per type of I/O: network, disk, UI, brick • Pool of worker threads for programmer tasks; Win32 fibers would be better but not available in WinCE When I/O request (e.g., file read) occurs in a task: • Event posted on relevant I/O thread; task scheduled out • I/O completes: result posted on scheduler thread • Worker thread resumed ultimately with result

More Related