On 8/3/24 5:06 PM, Finn Thain wrote: > > On Sat, 3 Aug 2024, Stan Johnson wrote: > >> >> root@m68k:/data# dump 0sbf 999999 64 dumpfile.dmp /dev/sda5 >> ... >> DUMP: Context save fork fails in parent 912 >> > > The manpage says, > > Each reel requires a new process, so parent processes for reels > already written just hang around until the entire tape is written. > > So I'd expect fork failures if the number of reels was too high. Have you > tried the default "auto-size" tape length instead of passing -s 999999? > > -a > auto-size. Bypass all tape length calculations, and write until an > end-of-media indication is returned. This works best for most > modern tape drives, and is the default. Use of this option is > particularly recommended when appending to an existing tape, or > using a tape drive with hardware compression (where you can never > be sure about the compression ratio). > > If auto-size works, that might indicate a bug in the tape length > calculations that would need to be reported. >
Thanks. I've never used the -a option. Dump has many good features, but it's always been a little clunky due to its long history of having to work with tape drives. Using "-a" appears to be a better option than just specifying a really long tape size. Unfortunately, it also doesn't work. The problem seems to affect only m68k; ppc-32, ppc-64, x86-32 and x86-64 all work as expected, probably with either "-a" or "-s 999999" (I've only tried the latter). # dump 0abf 64 Gentoo.dmp /dev/sda5 DUMP: Date of this level 0 dump: Sat Aug 3 18:28:52 2024 DUMP: Dumping /dev/sda5 (an unlisted file system) to Gentoo.dmp DUMP: Label: Gentoo-m68k DUMP: Writing 64 Kilobyte records DUMP: mapping (Pass I) [regular files] DUMP: mapping (Pass II) [directories] DUMP: estimated 1684360 blocks. DUMP: Context save fork fails in parent 3221 The failure happens immediately after the number of blocks is estimated, the output file isn't created, and no extra dump processes appear to have been created. In addition to Debian SID m68k, he issue also affects Gentoo m68k, at least as of my last Gentoo update (I'm updating Gentoo again now in QEMU after updating Debian SID earlier today). thanks -Stan
