Ok, folks, I just want to inject some bit of reality here. I've started working on Unix internals in 1980, and have worked ever since on just about any OS that has come my way--almost all variants of Unix, Linux, Windows, and a bunch of others that are irrelevant to this conversation. Why do I say this? To point out that I work in an heterogeneous environment, and have for a very long time. In the following, I respond both to Reindl, and the poster he's responding to (since I didn't save the original post); note the double-carats. Once, long ago--actually, on Sat, Jun 22, 2013 at 07:27:11AM CDT--Reindl Harald (h.reindl@xxxxxxxxxxxxx) said: > ... > Am 22.06.2013 14:18, schrieb Tim: > > Have you seen Windows complain at boot up that you hadn't shut down > > properly, and it needs to check the drive? ... We've all seen Unix/Linux have the same complaint, and force a fsck. ALL operating systems occasionally have cause to believe their filesystem(s) need checking. And ALL operating systems occasionally crash, or have filesystem issues. Also, since NTFS, the Windows filesystem has been at least as stable as most *nix variants in operation. > > ... > > Then you have the fun of waiting for it to scan through one hell > > of a huge drive. ... Never sat through a fsck of a really big *nix drive or array, have you? It's all a matter of the level of the check, allocation unit size, number of large files, and volume of data. > > More so if your computer likes to regularly screw up. > > which does typically not happen True. Quite seriously, Windows filesystems since NTFS are nowhere near as fragile as they used to be. Stability improved significantly after XP SP3, as well, and especially under Windows Server. > > Then there's drive fragmentation. Windows still seems to be horrid for > > that. I'd hate to have to wait for a 2 TB drive to defrag. Even if I > > wasn't watching the box, waiting for it to finish, because I wanted to > > use it, but left it overnight - it'd be at it all night > > which has nothing to do with *a disk* larger than 1 TB > it's more depending on the partitions you create Even more dependent on the allocation unit size selected at filesystem creation. > in context of Linux it doe snot matter at all Beg to differ. Do you all know how a file is strucured in *nix? There is a primary inode. In this are direct block pointers--the number varies depending on OS, filesystem type, etc.--but generally there are 12 pointers to direct blocks, 1 to single-indirect blocks, 1 to double-indirect blocks, and 1 to triple-indirect blocks. What does this mean? Well, essentially, *nix tries to optimize for small files--that is, files that can fit in twelve blocks. How big a block is depends on the allocation unit you picked when formatting the filesystem (as with NTFS). But once you go over that size, things start to get less efficient. Grow over the storage that can be addressed by direct file pointers, you have two lookups to carry out--on for the indirect block, then the pointers there. Double indirects guarantee three lookups; triple, four. And every one of the allocation units can be scattered anywhere on the disk--meaning that, after a while, yes, *nix is fragmented, too. NTFS has a similarly complicated, but very different, system for directory and file management. But it, too, ends up having mechanisms for dealing with larger files, and it, too, has to deal with fragmentation. And the effects of fragmentation have been reduced in NTFS over the earlier FAT filesystems. Both *nix and Windows play games with the disk drivers (f'rinstance, look up the elevator algorithm, and scatter-gather), caching, etc. to minimize the effect of fragmentation (as do, in fact, all operating systems). Disks have done their part to obfuscate the issue, since the allocation unit you think you're reading is certainly remapped internally by the disk firmware to different physical block(s). Both *nix and Windows play other games with their internal data structures to mitigate filesystem corruption and hardware failure--log files, multiple MFTs or primary inode tables, etc., and these have gotten both more complicated and sophisticated over time. Essentially, all filesystems fragment. All filesystems and operating systems have mechanisms to minimize the effects of fragmentation. And all have gotten very, very much better at it over time. We do no good to the cause of furthering the promulgation of Linux (I've given up on Unix _per se_) if we carelessly repeat canards that are no longer applicable, or at worst are much less applicable, when discussing the differences between operating systems. Enough pre-coffee pontificating. I just hit a tipping point, and had to point out that before we post something we "all know"--"Windows filesystems are fragile", "Linux doesn't fragment", etc.--we should think twice. Cheers, -- Dave Ihnat dihnat@xxxxxxxxxx -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
