dump/restore and DIRPREF
After Kris's recent report of 'massive speedups' using dirpref, I've been toying with the idea of backing up my box, and then restoring them. However, backup/restore are so much faster than doing a tar/untar. If I do a backup of my FS, wipe the disk, will the 'restore' cause the same (ineffecient) directory layout to appear on disk? I wouldn't think so since the directory layout is controlled by the kernel, but I do know that dump/restore are much lower-layer tools than tar, so they may possibly have layout information embedded in them. Is my assumption correct? Nate To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-hackers in the body of the message
Re: dump/restore and DIRPREF
On Tue, Oct 02, 2001 at 11:05:00AM -0600, Nate Williams wrote: If I do a backup of my FS, wipe the disk, will the 'restore' cause the same (ineffecient) directory layout to appear on disk? I wouldn't think so since the directory layout is controlled by the kernel, but I do know that dump/restore are much lower-layer tools than tar, so they may possibly have layout information embedded in them. Is my assumption correct? No. Dump reads the raw disk directly, but restore doesn't. Dump needs to in order to find the actual location of holes in files, but recreating them can be done in userland by simply seeking over them so there's no need to write directly to the raw disk on restore. Assuming you can read the dumps and you don't care about the file permissions, you can restore as any user. -- Brooks -- Any statement of the form X is the one, true Y is FALSE. PGP fingerprint 655D 519C 26A7 82E7 2529 9BF0 5D8E 8BE9 F238 1AD4 PGP signature
Re: dump/restore and DIRPREF
In message [EMAIL PROTECTED], Nate Williams writes : After Kris's recent report of 'massive speedups' using dirpref, I've been toying with the idea of backing up my box, and then restoring them. However, backup/restore are so much faster than doing a tar/untar. If I do a backup of my FS, wipe the disk, will the 'restore' cause the same (ineffecient) directory layout to appear on disk? I wouldn't think so since the directory layout is controlled by the kernel, but I do know that dump/restore are much lower-layer tools than tar, so they may possibly have layout information embedded in them. Is my assumption correct? no. Dump reads the raw device and finds everything by hand. Restore (like tar!) just open/write/close/chown regular files. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [EMAIL PROTECTED] | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-hackers in the body of the message
Re: dump/restore and DIRPREF
After Kris's recent report of 'massive speedups' using dirpref, I've been toying with the idea of backing up my box, and then restoring them. However, backup/restore are so much faster than doing a tar/untar. If I do a backup of my FS, wipe the disk, will the 'restore' cause the same (ineffecient) directory layout to appear on disk? I wouldn't think so since the directory layout is controlled by the kernel, but I do know that dump/restore are much lower-layer tools than tar, so they may possibly have layout information embedded in them. Is my assumption correct? no. Actually, yes, but I didn't word it very well above. Dump reads the raw device and finds everything by hand. Restore (like tar!) just open/write/close/chown regular files. So my assumption *is* correct that it won't matter if I use dump/restore to do the job, and that the lower-layer effeciencies of dump don't effect the resulting layout done by restore. Great, thanks for the quick response! Nate To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-hackers in the body of the message
Re: dump/restore and DIRPREF
I recommend using cpdup ( /usr/ports/sysutils/cpdup ), mainly because you can ^C it and restart it at any time so it's a lot easier to play around with your directory dup'ing. -Matt To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-hackers in the body of the message
