[fpc-pascal] Threads executing in sequence instead of parallel

Graeme Geldenhuys graemeg.lists at gmail.com
Thu Sep 28 16:31:26 CEST 2006

We have a problem!!!

The test project /fcl/tests/threads.pp as well as a Sort Demo (Bubble,
Section and Quick Sort) all execute the threads in sequence, waiting
for the previous thread to complete, before the next one executes.
Kind of defeats the point of using threads.

The Sort Demo, which is a port of the Threads demo included with
Delphi 7, shows this clearly.  I can archive and post the source, but
you would need Lazarus LCL to run it as it is visual. The sort demo
has three columns with identical random data.  The three sort methods
are applied to each column respectively and gives visual feedback as
it sorts the data (horizontal lines of different lengths).

The threads.pp test project in fcl, shown a lot of a's on the screen
and after a while, starts displaying b's on the screen.  Looking at
the source, I gather the a's and b's are supposed to be mixed as each
thread gets processor time.

I am using FPC 2.1.1 (svn version from a week ago) and running it
under Ubuntu Linux 6.10 on x86 CPU  (Pentium 4).

  - Graeme -

There's no place like

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