level-rawcopy

Optimized live copying of levelup instances.

Uses level-bufferstreams internally to optimize copy operations.

If you are using level-hyper it will attempt to use the LiveCopy feature.

NOTES: This is still experimental and has some issues on some LevelDOWN layers/versions. I am working those out.

var level = require("level")
var source = level("./your_source_db")
var target = level("./your_target_db")

var rawcopy = require("level-rawcopy")

rawcopy(source, target, function () {
  console.log("DONE!")
})

STATS

Comparing copies on a 180 megabyte level-hyper db:

db1.readStream().pipe(db2.writeStream())

{ rss: 3204366336, heapTotal: 1488523264, heapUsed: 1346318856 }
slowLoad: 382969ms

rawcopy(db1, db2)

{ rss: 656027648, heapTotal: 59279872, heapUsed: 28893008 }
fastLoad: 369023ms

Right now the speed is appears mostly bottle-necked by the iterator, see https://github.com/rvagg/node-leveldown/pull/34

API

rawcopy(source, target, options, callback)

Copies data from a LevelUP instance source into target. The target can be another LevelUP instance, or a path to a desired location. If a path is provided, you must also provide a LevelDOWN factory to use in options (same as when creating a levelup instance). Options also will respect level-bufferstreams options for the read and write ends.

LICENSE

MIT