Return to BSD News archive
Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!nntp.coast.net!news.kei.com!newsfeed.internetmci.com!news.sprintlink.net!news.us.world.net!ns2.mainstreet.net!bug.rahul.net!a2i!sierra.net!martis-d221 From: jiho@sunset.net (jiho@sunset.net) Newsgroups: comp.unix.bsd.misc Subject: Re: FreeBSD or NetBSD Date: Mon, 11 Dec 95 01:03:13 GMT Organization: Sierra-Net Lines: 69 Message-ID: <4ag00h$ckk_001@martis-d221.sierra.net> NNTP-Posting-Host: martis-d221.sierra.net X-Newsreader: News Xpress Version 1.0 Beta #3 > I've been using linux for some time and I feel I'd like to try > other unices and these two - FreeBSD and NetBSD - came to my mind > first. I hope I'm not totally wrong when posting to this group... > So, what are the diferences in getting them, copying policies, > hardware requirements, comparing running them as net servers and > as 'single' user workstations, ... thanks a LOT... I had FreeBSD for about two years, but recently switched to NetBSD, so I can compare the two somewhat for you, in certain respects. As noted by others, these systems are very similar, but there are some stark pros and cons on each side. FreeBSD is much better supported than is NetBSD. There is more work going on for FreeBSD, both in developing the kernel and in porting applications. The main negative I found for FreeBSD was the uncontrolled growth of the kernel code. In FreeBSD 2.1, the kernel I build for my hardware had ballooned to well over 700K. Meanwhile, with all the code that had been piled into the FreeBSD kernel, it really didn't do anything substantial that was new or different, even--let alone better--to justify the added size. The NetBSD kernel has remained much smaller, but the system is very poorly supported. The 1.0 release was riddled with absurd little problems. On the other hand, in NetBSD 1.0 the kernel I build (equivalent to the one for FreeBSD 2.1 that was well over 700K) is less than 500K. But even though some of 1.0's problems have been fixed for 1.1, my kernel in NetBSD 1.1 is about 35K larger than in 1.0, and already I am at a loss to find the reason; so the same trend seems to be developing for NetBSD, as drove me away from FreeBSD! Currently I have a "fixed" installation of NetBSD 1.0, and I've pretty much been turning away from both projects. My current thinking is to support and develop this system myself from here on. Very depressing. About the only thing to recommend either BSD over Linux is hard drive performance. The BSDs are very fast. FreeBSD 2.1 is a little faster, but not much. Linux's buffer cache scheme doesn't look very good next to FreeBSD's, at least for performance. The NetBSD community is still arguing about what to do with the buffer cache. BSD's task switching overhead is also much lower, because Linux uses the i386 TSS (Task State Segment) mechanism, where BSD just dumps a few registers. In my testing, Linux's TSS mechanism added overhead equivalent to one extra process eating a full time slice in the background. Neither BSD really has much over Linux in terms of RAM use efficiency. If you run X, any of these systems is fresh turkey. All three do crazy things with kernel memory overhead, like any Unix-type system. All three use pretty much the same inefficent shared library and LKM schemes, although Linux's runtime linker (ld.so) is smaller than *BSD's. The GNU libraries used by Linux are considerably fatter than the BSD libraries, but BSD's malloc functions, in libc and in the kernel, are hobbled by a ridiculous "bit bucket" scheme that doubles memory allocations in many situations. Linux kernel size is hard to analyze, because the kernel is compiled as a compressed image of its RAM usage, rather than as the usual executable file on disk. My impression is that it falls between NetBSD 1.1 and FreeBSD 2.1, and much much closer to NetBSD 1.1. Furthermore, the Linux kernel seems not to have grown at all in the past two years, despite having been rewritten for portability. But then, it was a tad fatter to start, I think. The Linux (Swansea) implementation of NFS is *tiny* compared to BSD's, and according to some reports, works better and more reliably besides. None of these systems is ideal. It's sort of like choosing among politicians running for office.... --Jim Howard