Editing the emerge --resume database (with a text editor)

When you run emerge --resume, emerge looks at /var/cache/edb/mtimedb to find the most recent entry in the resume list. Don’t worry about the scary name — this is just a JSON file with the following format:

{
	"info": { ... },
	"ldpath": { ... },
	"resume": { ... },
	"resume_backup": { ... },
	"starttime": 0,
	"updates": { ... },
	"version": "3.0.61"
}

resume and resume_backup are the keys we’re interested in.

Delete the most recent entry

If you’ve recently tried to update or reinstall a bunch of packages (say, with emerge --emptytree @world), but emerge’s process got interrupted, you no doubt want to resume this emerge at a later time. In the meantime, however, you might want to merge another package. No problem — if emerge fails to merge this package, it will back up emerge --emptytree @world’s progress into resume_backup and store the new command’s progress in resume. A call to emerge --resume will try to merge the new package again. If this fails, resume will be updated to contain the new progress (if progress was made). If it succeeds, resume_backup contents get moved into resume, whose contents get overwritten. If you’ve dabbled in programming, you should realize that this is just the world’s shortest fixed-length stack.

But what if the second merge failed because you entered the wrong command? Well, if you tried to correct this mistake by running a different command, and this command failed, its progress would get pushed to the top of the stack. Or, in English, the new command’s progress would get stored in resume, whose old contents (the previous failed attempt’s progress) would get stored in resume_backup, whose old contents (emerge --emptytree @world’s progress) would get discarded. This is no good!

There is a simple fix for this: Move the contents of resume_backup to resume by yourself. This emulates a successful run of emerge --resume.

You’ll probably want to back up /var/cache/edb/mtimedb before attempting this change for the first time.

For this example:

"resume": {
    "favorites": [
        "kde-plasma/plasma-pa"
    ],
    "mergelist": [
        [
            "ebuild",
            "/",
            "kde-plasma/plasma-pa-6.0.3",
            "merge"
        ]
    ],
    "myopts": {
        "--regex-search-auto": "y"
    }
},
"resume_backup": {
    "favorites": [
        "@world"
    ],
    "mergelist": [ ... ],
    "myopts": {
        "--emptytree": true,
        "--jobs": 12,
        "--keep-going": true,
        "--regex-search-auto": "y"
    }
},

You would delete each line from "favorites": [ to "resume_backup": {:

"resume": {
    "favorites": [
        "@world"
    ],
    "mergelist": [ ... ],
    "myopts": {
        "--emptytree": true,
        "--jobs": 12,
        "--keep-going": true,
        "--regex-search-auto": "y"
    }
},