From owner-freebsd-questions Tue Dec 16 12:37:57 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id MAA27214 for questions-outgoing; Tue, 16 Dec 1997 12:37:57 -0800 (PST) (envelope-from owner-freebsd-questions) Received: from silvester.zoom.es (root@silvester.zoom.es [195.76.150.4]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id MAA27189 for ; Tue, 16 Dec 1997 12:37:48 -0800 (PST) (envelope-from amora@zoom.es) Received: from zoom061.zoom.es (zoom061.zoom.es [195.76.150.61]) by silvester.zoom.es (8.7.5/8.7.3) with SMTP id WAA09873 for ; Tue, 16 Dec 1997 22:37:53 +0100 Message-Id: <199712162137.WAA09873@silvester.zoom.es> Comments: Authenticated sender is From: "Jesus A. Mora Marin" To: questions@FreeBSD.ORG Date: Tue, 16 Dec 1997 21:38:08 +0100 Subject: MFS related questions Reply-to: amora@zoom.es Priority: normal X-mailer: Pegasus Mail for Windows (v2.54) Sender: owner-freebsd-questions@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk Hi! I'd like to have MFS support configured in my custom kernel, partly for improving compilation times and partly just for fun. But I have some doubts about how MFS works in FreeBSD. First, according to the description of MFS in the "Design & implementation of 4.4 BSD Operating System", by McKusick et al., MFS is implemented in a paging on demand basis, and the kernel doesn't reserve a dedicated area of memory for it. I must supose that scheme is used in FreeBSD, isn't it? Does this mean that memory is not used anyway until blocks in the MFS are accessed? BTW, what's the exact meaning of the MFS_ROOT option in the kernel config file? My system has 32MB RAM and 48MB swap space, and the greater project I ever compiled is the custom kernel, or maybe `mysql'. What size would you recommend for MFS to get some benefit in compilation? Also, what is the impact of a larger MFS mounted, mainly in memory usage? TIA, Jesus ------ Jesus A. Mora Marin, MD. (aka EA7HAC, ex-EC7DVE)