RE: [Boost-users] RE: Boost thread problem

From: Sliwa, Przemyslaw (London) (Przemyslaw_Sliwa_at_[hidden])
Date: 2005-04-15 03:07:44

Hi,

Thanks for help,

On a Linux box I have to link against libc_r too?
Probably yes, but could you confirm this?

Thanks for help,

Pshemek

-----Original Message-----
From: boost-users-bounces_at_[hidden]
[mailto:boost-users-bounces_at_[hidden]] On Behalf Of C. Michailidis
Sent: 15 April 2005 00:02
To: boost-users_at_[hidden]
Subject: [Boost-users] RE: Boost thread problem

> It seems the usage of the vector cases problems with the multithreaded

programs on the multiprocessor machines. 
> I have changed it to queue and the bug has been resolved. I cannot
reproduce 
it now.

Huh, that's interesting!  I suppose it may no longer be a major issue
for you 
then (even though vectors and queues have different algorithms under the

hood).

Because you mentioned that the problem seems to be limited to true SMP 
systems, I tried your code again (this time on a dual cpu system) and I
still 
couldn't reproduce it.  I must admit that the process didn't seem to
bounce 
between cpus though, so perhaps something is lost in the shuffle in that

regard.  The dual cpu system was configured similarly to the first
machine 
that I tried it on (FreeBSD 5.3 + boost 1.32.0_2).  The first machine 
(although not a 'true' smp system) is using hyperthreading w/ an SMP
kernel 
so as far as the OS is concerned it too is a multiprocessor machine.

If you still want to isolate the problem that you *were* having (using
vector) 
then you may be interested in the details of thread-safe CRTs.

The "-lc_r" indicates that (on FreeBSD) the re-entrant C library (i.e. 
thread-safe) should be linked against.  On Windows I believe the analog
is 
called something like 'msvcrtmt.dll' (C RunTime - MultiThreaded).  I
would 
hope that the .NET compiler uses this 'msvcrtmt.dll' when 'multithreaded

support is on', but I couldn't tell you for sure.  If you're statically 
linking, I think the name is just 'msvcrtmt.lib'.  The thread-unsafe
version 
doesn't have 'mt' appended to the library filename.

The glamour of MSFT development has been largely replaced with a desire
to 
actually get stuff working so... most of my development has been on
FreeBSD 
lately.  Therefore some of this MSFT specific information may not be
exactly 
correct.  Oh how the cobwebs accumulate!

Anyway, you could probably double check for the 'msvcrtmt' library by
looking 
at the detailed linker settings, that is if my suspicion concerns you
and 
you're still interested in isolating the problem.

In any case, I'm glad you found a work-around!

C. Michailidis
Balston Research LLC
_______________________________________________
Boost-users mailing list
Boost-users_at_[hidden]
http://lists.boost.org/mailman/listinfo.cgi/boost-users
--------------------------------------------------------

If you are not an intended recipient of this e-mail, please notify the sender, delete it and do not read, act upon, print, disclose, copy, retain or redistribute it. Click here for important additional terms relating to this e-mail.     http://www.ml.com/email_terms/
--------------------------------------------------------