metrics: don't use horizontal table rendering

The horizontal table rendering is very unintuitive. We no longer need
it, given that we can customize both the vertical and horizontal
dividers. Change the only table that is using it.

Author: RaduBerinde

internal/ascii/table/table.go

@@ -308,6 +308,12 @@ func Int[T any](header string, width int, align Align, fn func(r T) int) Field[T
 	})
 }
 
+func Int64[T any](header string, width int, align Align, fn func(r T) int64) Field[T] {
+	return makeFuncField(header, width, align, func(tupleIndex int, tuple T) string {
+		return strconv.FormatInt(fn(tuple), 10)
+	})
+}
+
 func AutoIncrement[T any](header string, width int, align Align) Field[T] {
 	return makeFuncField(header, width, align, func(tupleIndex int, tuple T) string {
 		return strconv.Itoa(tupleIndex)

metrics.go

@@ -696,9 +696,19 @@ var (
 		table.Bytes("sstsz", 6, table.AlignRight, func(m *LevelMetrics) uint64 { return m.TableBytesFlushed + m.TableBytesCompacted }),
 		table.Bytes("blobsz", 6, table.AlignRight, func(m *LevelMetrics) uint64 { return m.BlobBytesFlushed + m.BlobBytesCompacted }),
 	)
-	compactionKindTable = table.Define[pair[string, int64]](
-		table.String("kind", 5, table.AlignRight, func(p pair[string, int64]) string { return p.k }),
-		table.Count("count", 5, table.AlignRight, func(p pair[string, int64]) int64 { return p.v }),
+	compactionKindTable = table.Define[*Metrics](
+		table.String("kind", 5, table.AlignRight, func(m *Metrics) string { return "count" }),
+		table.Div(),
+		table.Int64("default", 7, table.AlignRight, func(m *Metrics) int64 { return m.Compact.DefaultCount }),
+		table.Int64("delete", 7, table.AlignRight, func(m *Metrics) int64 { return m.Compact.DeleteOnlyCount }),
+		table.Int64("elision", 8, table.AlignRight, func(m *Metrics) int64 { return m.Compact.ElisionOnlyCount }),
+		table.Int64("move", 5, table.AlignRight, func(m *Metrics) int64 { return m.Compact.MoveCount }),
+		table.Int64("read", 5, table.AlignRight, func(m *Metrics) int64 { return m.Compact.ReadCount }),
+		table.Int64("tomb", 5, table.AlignRight, func(m *Metrics) int64 { return m.Compact.TombstoneDensityCount }),
+		table.Int64("rewrite", 8, table.AlignRight, func(m *Metrics) int64 { return m.Compact.RewriteCount }),
+		table.Int64("copy", 5, table.AlignRight, func(m *Metrics) int64 { return m.Compact.CopyCount }),
+		table.Int64("multi", 6, table.AlignRight, func(m *Metrics) int64 { return m.Compact.MultiLevelCount }),
+		table.Int64("blob", 5, table.AlignRight, func(m *Metrics) int64 { return m.Compact.BlobFileRewriteCount }),
 	)
 	commitPipelineInfoTableTopHeader = `COMMIT PIPELINE`
 	commitPipelineInfoTableSubHeader = `               wals                |              memtables              |       ingestions`
@@ -880,11 +890,6 @@ func makeCompressionInfo(algorithm string, table, blob CompressionStatsForSettin
 	return i
 }
 
-type pair[k, v any] struct {
-	k k
-	v v
-}
-
 // String pretty-prints the metrics.
 //
 // See testdata/metrics for an example.
@@ -921,19 +926,9 @@ func (m *Metrics) String() string {
 	cur.Offset(-1, 0).WriteString("total")
 
 	cur = cur.NewlineReturn()
-	compactionKindContents := []pair[string, int64]{
-		{k: "default", v: m.Compact.DefaultCount},
-		{k: "delete", v: m.Compact.DeleteOnlyCount},
-		{k: "elision", v: m.Compact.ElisionOnlyCount},
-		{k: "move", v: m.Compact.MoveCount},
-		{k: "read", v: m.Compact.ReadCount},
-		{k: "tomb", v: m.Compact.TombstoneDensityCount},
-		{k: "rewrite", v: m.Compact.RewriteCount},
-		{k: "copy", v: m.Compact.CopyCount},
-		{k: "multi", v: m.Compact.MultiLevelCount},
-		{k: "blob", v: m.Compact.BlobFileRewriteCount},
-	}
-	cur = compactionKindTable.Render(cur, table.RenderOptions{Orientation: table.Horizontally}, compactionKindContents...)
+	cur = compactionKindTable.Render(cur, table.RenderOptions{
+		HorizontalDividers: table.HorizontalDividers{},
+	}, m)
 	cur = cur.NewlineReturn()
 
 	commitPipelineInfoContents := commitPipelineInfo{