At Mon, 18 Nov 2013 12:31:42 +0100, Richard Braun wrote: > > On Mon, Nov 18, 2013 at 11:33:55AM +0100, Neal H. Walfield wrote: > > Richard Braun wrote: > > > The current state is to never terminate threads, on the assumption that > > > they can't both terminate and release their stack on their own. Such > > > resources are recycled by the threading library. This patch makes use > > > of a new GNU Mach specific call (thread_terminate_release [1]) so that > > > threads do terminate themselves and release their stack, and in addition > > > their last self reference, and their reply port. > > > > Eliminating bugs should be our first priority. However, recycling > > threads is a good idea, particularly when the application sees threads > > as lightweight resources. Ideally, there is some mechanism that > > identifies thread churn and sizes the reserve thread pool > > appropriately (e.g., the maximum of the maximum number of live threads > > during each minute in the past 5 minutes). Note: this isn't a reason > > not to apply the patch, but should perhaps be noted as possible future > > work. > > Personally, I consider this to be the responsibility of another > component, such as a work queue library. The threading library is a > low level component and should act as closely as its users expect it to.
I don't agree. On Linux, creating a thread is a pretty much a single system call. On a micro-kernel based system, there is a lot more work to do. This is a relatively straightforward optimization that doesn't changed the semantics of the operations. Neal
