At 8:49 AM -0500 3/16/06, John E. Malmberg wrote: >Craig A. Berry wrote: >>At 7:02 AM -0500 3/16/06, John E. Malmberg wrote: >> >>>I have found that the link command for executables needs to be >>>changed for threaded Perl build. The additional qualifiers are >>>ignored for shared images. >>> >>>I am not sure how to modify configure.com and descrip.mms_template >>>etc to do this. >>> >>>When building a threaded Perl, the link command should be: >>> >>>$LINK :== LINK/THREADS_ENABLE=(MULTIPLE,UPCALLS) >>> >>>Setting the above command before building Perl is the current work >>>around that I am using. >>> >>>This fixes t/op/threads.t to actually run test 4 instead of hanging. >> Thanks for tracking this down. The "workaround" should be to simply >>answer yes to the question: >> >>Enable multiple kernel threads and upcalls? >> >>at configuration time. We turn it off by default because there were >>problems with these options when first released some years ago. We >>should probably turn it on by default for VMS 7.2 and later, or maybe >>7.3. One reason I've never done that is that I have only >>single-processor systems to test on. > >I will look at configure.com then.
I may have spoken too soon. It looks like this option only affects compiling, not linking, so there may be a bit more configuration work to do. >My recommendation is that if threads are enabled, upcalls should also be >enabled by default. > >The multiple kernel threads can expose coding problems on a multi-processor >system, so enabling it as default may expose some problems. > >If someone has a multi-processor system available to test on, then I would >recommend seeing if there are any problems with multiple kernel threads >enabled. > >So for now, it may be safer to leave multiple kernel threads default to be off. OK, I suspect we'll have work to do to make things genuinely thread-safe, as I doubt this has ever been stress tested. I have the beginnings of a patch for our homegrown pipe implementation that tries to enhance thread safety. -- ____________________________________________ Craig A. Berry mailto:[EMAIL PROTECTED] "Literary critics usually know what they're talking about. Even if they're wrong." -- Perl creator Larry Wall
