On Thursday 03 March 2005 17:10, Theodore Ts'o wrote: > The e2defrag program had some problems where it only worked on 1k > blocksizes, if I remember correctly. It was also extremely dangerous > in that if it crashed or you had a system crash/powerfailure in middle > of the operation, your filesystem would be totally scrambled. > Therefore, the only safe way to use it was to do a full backup, and if > the system crashed, restore from the backup. > > Given that the filesystem had to be unmounted during the e2defrag > process, and combined with the fact that if you wanted to be safe, you > had to do a full backup of the data *anyway*, the time difference > between doing "backup; e2defrag; mke2fs and restore if your system > crashed" and "backup; mke2fs; restore" was such that it really wasn't > worth it. > > Mainly, there hasn't been sufficient interest to write a (safe, > effective) ext2 defragger. (There was one crazy person who didn't > believe me when I told him that an ext3 defragger couldn't be done > purely in userspace, until he banged his head against the wall enough > times, but that doesn't count. :-) Instead there has been more > interest in tweaking algorithsm that try to avoid the fragmentation > problem in the first place --- for example, such as the Orlov > allocator that got introduced during Linux 2.5. Another example is > the delayed allocation code plus the extent mapping extension that has > been currently discussed on ext2-devel. > > There has been talk about writing a kernel extension which implements > a few safe, atomic operations, such as relocating a logical block #w > in inode #x from block #y to #z, and "here are all the pathnames that > point at inode #x, relocate that inode to be stored at location #y", > and then implementing the rest in userspace. But it just hasn't risen > to the top of anyone's todo lists yet. Ok, given that's it not easily possible. How about a program that moves just the file's data to the start of the disk? AFAIK it doesn't work just to copy the files - you won't get them copied to a defined place, they'll end up in the various groups. Any idea how to make the startup process faster? Regards, Phil _______________________________________________ Ext3-users@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/ext3-users
