Ronny Haryanto <[EMAIL PROTECTED]> wrote on 12/12/2003 03:06:19 PM: > On 12-12-2003 2:40 PM Jhon Ramawi Putra wrote:
> > Perintah (misal format di DOS) yang tdk ada padanannya di Linux bukan > > berarti Linux tidak lengkap, namun memang tidak membutuhkannya. > Jangan bilang "tidak ada padanannya" dulu. Masa ada general purpose OS > yg gak butuh filesystem? Hehe. > Mencari padanan itu lebih ke mencari padanan dari apa yg dikerjakan oleh > tool itu, bukan sekedar namanya saja. Misalnya, perintah format di > DOS/windows itu sebetulnya adalah membuat filesystem bukan betul2 format > (yg ini biasanya disebut low-level format), sedangkan di Unix namanya > sesuai dg apa yg dikerjakan, yaitu mkfs (make filesystem). Coba 'man mkfs'. Setuju..., dan list itu hanya mencoba menjawab apa kira-kira tool yang mirip dengan DOS. Mungkin cara penyampaian saya terlalu "plain" nih :) ... karena selama ini, banyak rekan rekan saya yang baru beralih ke Linux bingung apa "padanan" perintah2 yang familiar bagi mereka di DOS ketika menggunakan Linux. > > Sama juga ketika ada pertanyaan apakah ada perintah Disk Defragmenter > > di Linux. > Sama apanya nih, dan dengan yg mana? Filesystem apa yg mau didefrag? > ext2/3, reiserfs, xfs? > Ronny Sama, pertanyaan apakah ada utility file defragmenter "mirip" seperti yang biasa ditemui di M$. --------SNIP -----(From Kenneth Goodwin)-------------- 1) The FS drivers are Part of the OS. 2) Removing files as part of the reboot or CRON run process has nothing to do with Defrag, it's just good housekeeping practice. 3) Since the rise of the 4BSD UNIX filesystem and the children it spawn, UNIX has had sort of, I repeat sort of, a form of auto - defrag, in that such FS data structure layouts as the 4BSD "cylinder groups, Logical Block/Physical block, and auto space reserve" tend to leave the growth room for files where it is needed - right in the same disk section as where the file was created. The kind of wild fragmentation you see on windows systems tends to take longer to reach under a UNIX system. The other reason why *NIX systems tend not to be "as fragged" is that we layout, "ORGANIZE", the drives in such a fashion as to place high rate of change files under specific filesystems - ie /tmp, /var/tmp, /var/spool, swap for example and static files on separate filesystems. /, /boot, /usr, /var. windows lumps all of this under the C: partition. 4)Should we have a defrag program?, IMHO, yes, run at boot time, before anything else is launched, with software mirroring taken into account, and triggered on a per filesystem basis when the IO Subsystem detects "high" head swings reading/writing a large enough percentages of the files on a filesystem. IE - the FS is fragged enough to warrant a defrag operation on next boot. It should set a defrag Flag in the superblock. This requires some additional thought, but off the top of my head, Probably need to change the on-disk Inode structures to hold statistical usage data on a per file basis - rate of growth, truncations, average size of growth so you can determine placement of the file on the new defrag image as well as free space to leave in the region. I thought about actually doing this under the UNIX V6 kernel. If you can stored in the inode how the file is accessed, you can control READ-AHead operations with a finer per file granularity. You could do this as an external utility program and database as well by having it read and follow the Inode structures to determine file level fragmentation. Speed wise, would probably help if each drive had a special DEFRAG partition large enough to hold the biggest FS on the system plus defrag process state information. fastest way to defrag is to copy off, purge original , and sort the files and directories appropriately and copy back. There would have to be another Superblock bit flag to restrict defrag to "IN-place" for such FS as / and /boot. INPLACE only defrag partitions should be kept small and as static as possible. Another SB flag for DEFRAG in progress and a reserve flag for the defrag temp partition to secure things in case of a crash during a defrag operation. --------SNIP --------------------------------------------- Best Regards, Jhon Ramawi Putra -- Unsubscribe: kirim email kosong ke [EMAIL PROTECTED] Arsip dan info di http://linux.or.id/milis.php FAQ milis http://linux.or.id/faq.php
