From owner-freebsd-chat Mon Aug 28 01:51:59 1995 Return-Path: chat-owner Received: (from majordom@localhost) by freefall.FreeBSD.org (8.6.11/8.6.6) id BAA13119 for chat-outgoing; Mon, 28 Aug 1995 01:51:59 -0700 Received: from irz301.inf.tu-dresden.de (irz301.inf.tu-dresden.de [141.76.1.11]) by freefall.FreeBSD.org (8.6.11/8.6.6) with ESMTP id BAA13107 for ; Mon, 28 Aug 1995 01:51:45 -0700 Received: from sax.sax.de by irz301.inf.tu-dresden.de (8.6.12/8.6.12-s1) with ESMTP id KAA28966 for ; Mon, 28 Aug 1995 10:51:36 +0200 Received: by sax.sax.de (8.6.11/8.6.12-s1) with UUCP id KAA10926 for freebsd-chat@freebsd.org; Mon, 28 Aug 1995 10:51:35 +0200 Received: (from uucp@localhost) by uriah.heep.sax.de (8.6.11/8.6.9) with UUCP id KAA11201 for freebsd-chat@freebsd.org; Mon, 28 Aug 1995 10:28:22 +0200 Received: by bonnie.tcd-dresden.de (8.6.8/8.6.6) id KAA26470; Mon, 28 Aug 1995 10:06:01 +0200 Date: Mon, 28 Aug 1995 10:06:01 +0200 From: j@bonnie.heep.sax.de (J Wunsch) Message-Id: <199508280806.KAA26470@bonnie.tcd-dresden.de> To: freebsd-chat@freebsd.org Subject: Re: Linux or FreeBSD Reply-To: freebsd-chat@freebsd.org Newsgroups: comp.unix.bsd.freebsd.misc In-Reply-To: <41l9eo$17h@park.uvsc.edu> References: <409iah$inf@galaxy.ucr.edu> <40alp5$psg@agate.berkeley.edu> <413bkc$3t2@kadath.zeitgeist.net> <1995Aug24.222509.28085@state.systems.sa.gov.au> <41ko58$rqh@hamilton.maths.tcd.ie> Organization: Private U**x site, Dresden. Sender: chat-owner@freebsd.org Precedence: bulk For those who haven't seen it, finally a technically interesting comparision between the various free unix systems, by Terry: In article <41l9eo$17h@park.uvsc.edu> you write: >tim@maths.tcd.ie (Timothy Murphy) wrote: >] I run Linux and FreeBSD, and I have never noticed the slightest difference. >] >] I read all these comments, "FreeBSD does this better", "Linux does that better", >] and I just wonder how many of the posters have actually tested their conclusions. >] >] In my view, the only serious difference is that Linux documentation is much better. >] I said this before, and was flamed for my impertinence. >] In fact, I only mentioned it to suggest that if FreeBSD is to flourish >] it ought to look to its documentation. >] >] Personally, I think there is room in the world for Linux and FreeBSD. > >Me too. > >However, I run both Linux and FreeBSD on a daily basis, and I have >to say that a single packet drop takes a lot longer to recover from >on Linux. I don't notice anything on BSD, but there appears to be >some problem with the TCP restart timers that I haven't bothered >to track down on Linux yet. > >Basically, the BSD box will still get packets through, whereas the >Linux box wil drop the rlogin connection. > >This mostly occurs when I'm starting up elm on a remote system >where I typically have a 2500 message mailbox. > >On a noisy net connection (Alternet), I use the Linux box as an X >terminal for the BSD box to go out, rather than going out directly >from the Linux box to work around the problem. > > >The BSD box seemed to get "hiccups" -- that is, the program startup >of an xterm from the linux box is not instantaneous. I thought >this was a problem with the fill algorithm on the BSD disk caching, >meaning it was waiting for a free block. Turns out that this is a >Linux problem with swapping the X window manager (twm) when the >box is busy. > > >BSD still negotiates linemode when telnetting to some Solaris >boxes. Bloody annoying -- so does Windows 95's Telnet, and so >does Linux, though. mostly it's a screwup caused by using "resize" >from OpenWin3 in your .cshrc. > > >I've done kernel developement in both BSD and Linux. For the most >part, the BSD kernel is an easier environment to develop in, but >the Linux environment has several plusses as well. The first plus >is the kernel module loading interface in Linux is much closer to >my original design for BSD, with the restricted exported symbol >list. I'm allowed to criticise BSD's method because I designed it >back before Novell bought USL as a stopgap for console developement. > >The second plus in the Linux kernel is also a minus. Linux copies >in path names from user space using a single routine; it does not >have a copyinstr. This is both bad and good. It's good because >some of the hacking I'm doing now could benefit greatly from having >just one point to change. BSD uses copyinstr to pull in pathnames, >pathnames used as data, pathnames used as hybridized data, strings >that are data, and pathnames explicitly pulled in for binary >compatability. This is also bad, since Linux can't support the >data usage or the binary compatability usage without a lot of >extra warts. Host names for NFS mounts using a kernel NFS client, >login names for setlogin/getlogin, module names for the kernel >module unload, and environment strings translated for binary >compatability all fall into the "wart" category on Linux. I've >sent several patches in through friends who are involved in the >Linux community to file system code. > >Other than that, BSD's kernel design is more orthogonal. The >binary compatability issues have been most elegantly solved by >NetBSD, though they too have their warts (they effectively use >variant symbolic links, but the special case the lookup code >to get hit twice with a relative path rather than implementing >real variant symbolic links or the logcal naming support needed >to make them really work). FreeBSD is the next most elegant, and >Linux is probably least elegant because of the aformentioned >binary compatability warts. > >Linux is suboptimal in the error case. In many instances, an >error will amplify and become a full blown problem. I've sent >several patches in through friends who are involved in the Linux >community... none are explicitly from me, but they *are* there. > >As far as distributions are concerned, well, FreeBSD is most >uniform, followed by Linux (though you have to pick the one you >get with care -- there are many Linux distributions, even if >there is only one true kernel), followed by NetBSD (they spend >their time porting, not packaging). With FreeBSD, the file >locations, and which files constitute a part of the distribution, >don't change as arbitrarily as they do in Linux. > > >The Linux move towards STREAMS (as bad as STREAMS is in many >peoples opinions) opens up the possibility of running more >commercial code. Like the NetWare for UNIX server. There is >occasional noise on the Samba list about writing a NetWare >server -- why hasn't this been done? Well, you are over 400 >NCP's which you have to support, none of which you can obtain >a description for without non-disclosure prohibiting you from >building a NetWare server. It's a near impossible task (even >the commercial NetWare clones, as in Windows NT and Puzzle systems. >don't correctly implement everything that's needed -- they need >a NetWare server on the wire and they need to use Novell's >utilities). So STREAMS is a plus for Linux, though it's long >term and shouldn't factor into a short term decision. > > >Documentation is an issue, but it's also a red herring. There is >a significant amount of printed literature that deals with BSD >and UNIX that is directly applicable to BSD. It's just not >necessarily labelled "BSD". The Linux documentation that exists >is rarely more useful than the printed materials not specific to >BSD when it comes to doing "interesting things". The main cry >in these cases (like writing device drivers) is that "the source >code is the documentation". > > >If you take a good, hard look under the sheets, there are massive >differences between FreeBSD and NetBSD, let alone either of them >and Linux. Unfortunately, all three are moving targets, so it's >not possible to provide a fair qualatative analysis without getting >flames to death by people who fix the problems you note in the >analysis between the time you note them and the time you post >about them (or worse: fix them between the first and second posting >and then flame you for the second posting. 8-)). > > > Terry Lambert > terry@cs.weber.edu >--- >Any opinions in this posting are my own and not those of my present >or previous employers. > -- cheers, J"org private: joerg_wunsch@uriah.heep.sax.de http://www.sax.de/~joerg/ Never trust an operating system you don't have sources for. ;-)