From owner-freebsd-hackers@FreeBSD.ORG Wed May 28 13:05:14 2008 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E5F221065687 for ; Wed, 28 May 2008 13:05:14 +0000 (UTC) (envelope-from freebsd-hackers@m.gmane.org) Received: from ciao.gmane.org (main.gmane.org [80.91.229.2]) by mx1.freebsd.org (Postfix) with ESMTP id 891328FC67 for ; Wed, 28 May 2008 13:05:14 +0000 (UTC) (envelope-from freebsd-hackers@m.gmane.org) Received: from list by ciao.gmane.org with local (Exim 4.43) id 1K1KtW-0003Gz-Ou for freebsd-hackers@freebsd.org; Wed, 28 May 2008 12:36:42 +0000 Received: from lara.cc.fer.hr ([161.53.72.113]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 28 May 2008 12:36:42 +0000 Received: from ivoras by lara.cc.fer.hr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 28 May 2008 12:36:42 +0000 X-Injected-Via-Gmane: http://gmane.org/ To: freebsd-hackers@freebsd.org From: Ivan Voras Date: Wed, 28 May 2008 14:36:33 +0200 Lines: 36 Message-ID: Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigC95AF5E91E39B4F62DCFA8C1" X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: lara.cc.fer.hr User-Agent: Thunderbird 2.0.0.14 (X11/20080505) X-Enigmail-Version: 0.95.0 Sender: news Subject: Impact of having a large number of open file descriptors X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 28 May 2008 13:05:15 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigC95AF5E91E39B4F62DCFA8C1 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Hi, Im thinking again of the old idea of implementing poor man's file replication system using kqueue to monitor changes on files. This would require opening every file that needs to be monitored and using EVFILT_VNODE to monitor them. I suppose this would work for a small-ish number of files like for a user's home directory but what about 100,000 files or millions of files? One other question: do kqueue events "coalesce" in the sense that if N operations happen (like write()s), there can be < N events passed to the kqueue (NOTE_WRITE)? While at it, will EVFILT_VNODE and NOTE_WRITE catch "additional" ways the file can be modified, meaning mmap()? --------------enigC95AF5E91E39B4F62DCFA8C1 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQFIPVHRldnAQVacBcgRApuWAJ4trf/Hfti+FUCLRTFA6Gub8pBtbwCg6hsB hdEBNMuxNHiZw9Fi0By/HsA= =1uvQ -----END PGP SIGNATURE----- --------------enigC95AF5E91E39B4F62DCFA8C1--