Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 18 Sep 2002 02:57:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 18 Sep 2002 02:57:22 -0400 Received: from cpe-24-221-190-179.ca.sprintbbd.net ([24.221.190.179]:6849 "EHLO myware.akkadia.org") by vger.kernel.org with ESMTP id ; Wed, 18 Sep 2002 02:57:21 -0400 Message-ID: <3D882500.2000105@redhat.com> Date: Wed, 18 Sep 2002 00:02:24 -0700 From: Ulrich Drepper User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.1b) Gecko/20020812 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Dan Kegel CC: linux-kernel@vger.kernel.org Subject: Re: Hardware limits on numbers of threads? References: <3D88208E.8545AAA2@kegel.com> X-Enigmail-Version: 0.65.1.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1641 Lines: 42 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Dan Kegel wrote: > http://people.redhat.com/drepper/glibcthreads.html says: > > >>Hardware restrictions put hard limits on the number of >>threads the kernel can support for each process. >>Specifically this applies to IA-32 (and AMD x86_64) where the thread >>register is a segment register. The processor architecture >>puts an upper limit on the number of segment register values >>which can be used (8192 in this case). > > > Is this true? Where does the limit come from? This was and is true with the kernel before 2.5.3 when Ingo introduced TLS support since the thread specific data had to be addressed via LDT entries and the LDT holds at most 8192 entries. The GDT based solution now implemented in the kernel has no such limitation and the number of threads you can create with the new thread library is only limited by system resources. - -- - ---------------. ,-. 1325 Chesapeake Terrace Ulrich Drepper \ ,-------------------' \ Sunnyvale, CA 94089 USA Red Hat `--' drepper at redhat.com `------------------------ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.7 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQE9iCUE2ijCOnn/RHQRAgqyAJ0e88AQXpxXoHrvZCxIhfZXJFJP9QCbBlCL nXUfQkt00sX+XsHg89OZz+k= =NkZd -----END PGP SIGNATURE----- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/