Function TestDiscardFirstVersion

levels_test.go:598–647

This is a test to ensure that the first entry with DiscardEarlierversion bit < DiscardTs is kept around (when numversionstokeep is infinite).

(t *testing.T)

// This is a test to ensure that the first entry with DiscardEarlierversion bit < DiscardTs
// is kept around (when numversionstokeep is infinite).
func TestDiscardFirstVersion(t *testing.T) {
	opt := DefaultOptions("")
	opt.NumCompactors = 0
	opt.NumVersionsToKeep = math.MaxInt32
	opt.managedTxns = true

	runBadgerTest(t, &opt, func(t *testing.T, db *DB) {
		l0 := []keyValVersion{{"foo", "bar", 1, 0}}
		l01 := []keyValVersion{{"foo", "bar", 2, bitDiscardEarlierVersions}}
		l02 := []keyValVersion{{"foo", "bar", 3, 0}}
		l03 := []keyValVersion{{"foo", "bar", 4, 0}}
		l04 := []keyValVersion{{"foo", "bar", 9, 0}}
		l05 := []keyValVersion{{"foo", "bar", 10, bitDiscardEarlierVersions}}

		// Level 0 has all the tables.
		createAndOpen(db, l0, 0)
		createAndOpen(db, l01, 0)
		createAndOpen(db, l02, 0)
		createAndOpen(db, l03, 0)
		createAndOpen(db, l04, 0)
		createAndOpen(db, l05, 0)

		// Discard Time stamp is set to 7.
		db.SetDiscardTs(7)

		// Compact L0 to L1
		cdef := compactDef{
			thisLevel: db.lc.levels[0],
			nextLevel: db.lc.levels[1],
			top:       db.lc.levels[0].tables,
			bot:       db.lc.levels[1].tables,
		}
		require.NoError(t, db.lc.runCompactDef(0, cdef))

		// - Version 10, 9 lie above version 7 so they should be there.
		// - Version 4, 3, 2 lie below the discardTs but they don't have the
		//   "bitDiscardEarlierVersions" versions set so they should not be removed because number
		//    of versions to keep is set to infinite.
		// - Version 1 is below DiscardTS and below the first "bitDiscardEarlierVersions"
		//   marker so IT WILL BE REMOVED.
		ExpectedKeys := []keyValVersion{
			{"foo", "bar", 10, bitDiscardEarlierVersions},
			{"foo", "bar", 9, 0},
			{"foo", "bar", 4, 0},
			{"foo", "bar", 3, 0},
			{"foo", "bar", 2, bitDiscardEarlierVersions}}

		getAllAndCheck(t, db, ExpectedKeys)
	})
}

// This test ensures we don't stall when L1's size is greater than opt.LevelOneSize.
// We should stall only when L0 tables more than the opt.NumLevelZeroTableStall.