Re: [Boost-users] Understanding Threads: Slow on Win32 with DLL

Subject: Re: [Boost-users] Understanding Threads: Slow on Win32 with DLL
From: Nat Linden (nat_at_[hidden])
Date: 2010-11-30 22:22:01

On Tue, Nov 30, 2010 at 4:38 PM, Simon Adler <boost_at_[hidden]> wrote:

If I use all threads all four cpus are in 100% usage - they are all together
> working but require more
> than twice the time - Yes i am sure that every thread is just working on
> 2500 Elements.
>

Hmm, are you sure of that because the different threads are all producing
log output, perhaps to std::cout?

I wonder if there's some unobvious shared resource (such as an ostream)
that's being properly locked against concurrent access, but the locking is
inducing the delay you're observing.