From owner-freebsd-hackers Thu Jul 27 22:41:35 2000 Delivered-To: freebsd-hackers@freebsd.org Received: from mta5.rcsntx.swbell.net (mta5.rcsntx.swbell.net [151.164.30.29]) by hub.freebsd.org (Postfix) with ESMTP id E42C737B50D for ; Thu, 27 Jul 2000 22:41:32 -0700 (PDT) (envelope-from chris@holly.calldei.com) Received: from holly.calldei.com ([208.191.149.190]) by mta5.rcsntx.swbell.net (Sun Internet Mail Server sims.3.5.2000.01.05.12.18.p9) with ESMTP id <0FYE0024Y7SCSZ@mta5.rcsntx.swbell.net> for freebsd-hackers@FreeBSD.ORG; Fri, 28 Jul 2000 00:41:00 -0500 (CDT) Received: (from chris@localhost) by holly.calldei.com (8.9.3/8.9.3) id AAA41058; Fri, 28 Jul 2000 00:39:14 -0500 (CDT envelope-from chris) Date: Fri, 28 Jul 2000 00:39:14 -0500 From: Chris Costello Subject: Re: BSD,Posix,Linux Threading - Are they really useable? In-reply-to: <398111DA.443B41F9@tornqvist.net> To: Bjorn Tornqvist Cc: freebsd-hackers@FreeBSD.ORG Reply-To: chris@calldei.com Message-id: <20000728003913.K37935@holly.calldei.com> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii User-Agent: Mutt/0.96.4i References: <398111DA.443B41F9@tornqvist.net> Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Friday, July 28, 2000, Bjorn Tornqvist wrote: > PosixThreads are userland threads - if one thread blocks on i/o the > whole process is blocked. Which makes PosixThreads rather useless. That is incorrect. FreeBSD's userland pthread implementation does not block the whole process on I/O. POSIX does not specify this behavior either. > FreeBSD Kernel-threads (dunno what they are called actually) can't be > used natively!? (Searched the archives and found an explanation that the > only way to access normal kernel SMP-thread functionality is to use > LinuxThreads) FreeBSD's kernel threads are for separate threads of execution in the kernel and aren't the same thing as threads for a user process. > LinuxThreads: While they are kernel-threads, if one thread receives an > uncought signal, all threads are killed (as they should be), but the > resulting coredump is useless since it only captures the state of the > last-killed-thread (or process or whatever you want to call it. > LinuxThreads seems like just a big hack...). LinuxThreads on FreeBSD cannot be kernel threads because that would require modifications to our scheduler which simply have not been made. -- |Chris Costello |Save energy: Drive a smaller shell. `------------------------------------ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message