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Merged
merged 1 commit into from
Nov 6, 2025
+161 −100
Merged

db: add metric encapsulating blob file rewrite bytes read, written #5525

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10 changes: 9 additions & 1 deletion blob_rewrite.go
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Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,7 @@ import (
"github.com/cockroachdb/pebble/sstable"
"github.com/cockroachdb/pebble/sstable/blob"
"github.com/cockroachdb/pebble/sstable/block"
"github.com/cockroachdb/pebble/sstable/block/blockkind"
"github.com/cockroachdb/pebble/sstable/colblk"
)

Expand Down Expand Up @@ -242,8 +243,15 @@ func (c *blobFileRewriteCompaction) Execute(jobID JobID, d *DB) error {
d.mu.versions.incrementCompactions(compactionKindBlobFileRewrite, nil, c.bytesWritten.Load(), err)
d.mu.versions.incrementCompactionBytes(-c.bytesWritten.Load())

// Update the read state to publish the new version.
if err == nil {
// Record bytes read and written for blob file rewrite compactions.
// These metrics are separate from per-level metrics since blob file
// rewrites don't contribute to per-level compacted bytes.
bytesRead := c.internalIteratorStats.BlockReads[blockkind.BlobValue].BlockBytes
d.mu.versions.metrics.Compact.BlobFileRewrite.BytesRead += int64(bytesRead)
d.mu.versions.metrics.Compact.BlobFileRewrite.BytesWritten += c.bytesWritten.Load()

// Update the read state to publish the new version.
d.updateReadStateLocked(d.opts.DebugCheck)
}

Expand Down
48 changes: 36 additions & 12 deletions metrics.go
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Original file line number Diff line number Diff line change
Expand Up @@ -426,6 +426,20 @@ type CompactMetrics struct {
// Duration records the cumulative duration of all compactions since the
// database was opened.
Duration time.Duration
// BlobFileRewrite contains metrics for blob file rewrite compactions.
BlobFileRewrite struct {
// The total number of bytes read during blob file rewrite compactions.
// This only counts blob value blocks (data blocks) that are read from
// the input blob file. The index block is read but tracked as
// blockkind.Metadata, not blockkind.BlobValue. As a result, BytesRead
// can be smaller than BytesWritten.
BytesRead int64
// The total number of bytes written during blob file rewrite compactions.
// This counts all bytes written to the output blob file, including blob
// value blocks, index block, properties block, and footer. As a result,
// BytesWritten can be larger than BytesRead.
BytesWritten int64
}
}

// IngestMetrics contains metrics related to ingestions.
Expand Down Expand Up @@ -767,16 +781,21 @@ var (
table.String("tot", 13, table.AlignRight, func(i cgoMemInfo) string { return i.memtablesTot }),
)
compactionInfoTableTopHeader = `COMPACTIONS`
compactionInfoTableSubHeader = ` | blob rewrites`
compactionInfoTable = table.Define[compactionMetricsInfo](
table.String("estimated debt", 17, table.AlignRight, func(i compactionMetricsInfo) string { return i.estimatedDebt }),
table.String("est. debt", 13, table.AlignRight, func(i compactionMetricsInfo) string { return i.estimatedDebt }),
table.Div(),
table.String("in progress", 13, table.AlignRight, func(i compactionMetricsInfo) string { return i.inProgress }),
table.Div(),
table.String("cancelled", 10, table.AlignRight, func(i compactionMetricsInfo) string { return i.cancelled }),
table.Div(),
table.String("in progress", 17, table.AlignRight, func(i compactionMetricsInfo) string { return i.inProgress }),
table.String("failed", 8, table.AlignRight, func(i compactionMetricsInfo) string { return fmt.Sprint(i.failed) }),
table.Div(),
table.String("cancelled", 17, table.AlignRight, func(i compactionMetricsInfo) string { return i.cancelled }),
table.String("problem spans", 16, table.AlignRight, func(i compactionMetricsInfo) string { return i.problemSpans }),
table.Div(),
table.String("failed", 17, table.AlignRight, func(i compactionMetricsInfo) string { return fmt.Sprint(i.failed) }),
table.String("read", 10, table.AlignRight, func(i compactionMetricsInfo) string { return i.blobFileRewriteBytesRead }),
table.Div(),
table.String("problem spans", 18, table.AlignRight, func(i compactionMetricsInfo) string { return i.problemSpans }),
table.String("written", 10, table.AlignRight, func(i compactionMetricsInfo) string { return i.blobFileRewriteBytesWritten }),
)
keysInfoTableTopHeader = `KEYS`
keysInfoTable = table.Define[keysInfo](
Expand Down Expand Up @@ -902,11 +921,13 @@ type cgoMemInfo struct {
}

type compactionMetricsInfo struct {
estimatedDebt string
inProgress string
cancelled string
failed int64
problemSpans string
estimatedDebt string
inProgress string
cancelled string
failed int64
problemSpans string
blobFileRewriteBytesRead string
blobFileRewriteBytesWritten string
}

type keysInfo struct {
Expand Down Expand Up @@ -1119,10 +1140,13 @@ func (m *Metrics) String() string {
humanizeBytes(m.Compact.InProgressBytes)),
cancelled: fmt.Sprintf("%s (%s)", humanizeCount(m.Compact.CancelledCount),
humanizeBytes(m.Compact.CancelledBytes)),
failed: m.Compact.FailedCount,
problemSpans: fmt.Sprintf("%d%s", m.Compact.NumProblemSpans, ifNonZero(m.Compact.NumProblemSpans, "!!")),
failed: m.Compact.FailedCount,
problemSpans: fmt.Sprintf("%d%s", m.Compact.NumProblemSpans, ifNonZero(m.Compact.NumProblemSpans, "!!")),
blobFileRewriteBytesRead: humanizeBytes(m.Compact.BlobFileRewrite.BytesRead),
blobFileRewriteBytesWritten: humanizeBytes(m.Compact.BlobFileRewrite.BytesWritten),
}
cur = cur.WriteString(compactionInfoTableTopHeader).NewlineReturn()
cur = cur.WriteString(compactionInfoTableSubHeader).NewlineReturn()
cur = compactionInfoTable.Render(cur, table.RenderOptions{}, compactionMetricsInfoContents)
cur = cur.NewlineReturn()

Expand Down
7 changes: 4 additions & 3 deletions testdata/compaction/l0_to_lbase_compaction
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Original file line number Diff line number Diff line change
Expand Up @@ -98,9 +98,10 @@ CGO MEMORY | block cache | memtables
0B | 0B | 0B | 0B | 0B | 0B

COMPACTIONS
estimated debt | in progress | cancelled | failed | problem spans
------------------+-------------------+-------------------+-------------------+-------------------
0B | 0 (0B) | 0 (0B) | 0 | 0
| blob rewrites
est. debt | in progress | cancelled | failed | problem spans | read | written
--------------+---------------+------------+----------+------------------+------------+-----------
0B | 0 (0B) | 0 (0B) | 0 | 0 | 0B | 0B

KEYS
range keys | tombstones | missized tombstones | point dels | range dels
Expand Down
14 changes: 8 additions & 6 deletions testdata/compaction/value_separation
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Original file line number Diff line number Diff line change
Expand Up @@ -216,9 +216,10 @@ CGO MEMORY | block cache | memtables
0B | 0B | 0B | 0B | 0B | 0B

COMPACTIONS
estimated debt | in progress | cancelled | failed | problem spans
------------------+-------------------+-------------------+-------------------+-------------------
0B | 0 (0B) | 0 (0B) | 0 | 0
| blob rewrites
est. debt | in progress | cancelled | failed | problem spans | read | written
--------------+---------------+------------+----------+------------------+------------+-----------
0B | 0 (0B) | 0 (0B) | 0 | 0 | 0B | 0B

KEYS
range keys | tombstones | missized tombstones | point dels | range dels
Expand Down Expand Up @@ -544,9 +545,10 @@ CGO MEMORY | block cache | memtables
0B | 0B | 0B | 0B | 0B | 0B

COMPACTIONS
estimated debt | in progress | cancelled | failed | problem spans
------------------+-------------------+-------------------+-------------------+-------------------
0B | 0 (0B) | 0 (0B) | 0 | 0
| blob rewrites
est. debt | in progress | cancelled | failed | problem spans | read | written
--------------+---------------+------------+----------+------------------+------------+-----------
0B | 0 (0B) | 0 (0B) | 0 | 0 | 83B | 150B

KEYS
range keys | tombstones | missized tombstones | point dels | range dels
Expand Down
7 changes: 4 additions & 3 deletions testdata/compaction/virtual_rewrite
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Original file line number Diff line number Diff line change
Expand Up @@ -201,9 +201,10 @@ CGO MEMORY | block cache | memtables
0B | 0B | 0B | 0B | 0B | 0B

COMPACTIONS
estimated debt | in progress | cancelled | failed | problem spans
------------------+-------------------+-------------------+-------------------+-------------------
0B | 0 (0B) | 0 (0B) | 0 | 0
| blob rewrites
est. debt | in progress | cancelled | failed | problem spans | read | written
--------------+---------------+------------+----------+------------------+------------+-----------
0B | 0 (0B) | 0 (0B) | 0 | 0 | 0B | 0B

KEYS
range keys | tombstones | missized tombstones | point dels | range dels
Expand Down
14 changes: 8 additions & 6 deletions testdata/event_listener
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Original file line number Diff line number Diff line change
Expand Up @@ -348,9 +348,10 @@ CGO MEMORY | block cache | memtables
0B | 0B | 0B | 0B | 0B | 0B

COMPACTIONS
estimated debt | in progress | cancelled | failed | problem spans
------------------+-------------------+-------------------+-------------------+-------------------
1.9KB | 0 (0B) | 0 (0B) | 0 | 0
| blob rewrites
est. debt | in progress | cancelled | failed | problem spans | read | written
--------------+---------------+------------+----------+------------------+------------+-----------
1.9KB | 0 (0B) | 0 (0B) | 0 | 0 | 0B | 0B

KEYS
range keys | tombstones | missized tombstones | point dels | range dels
Expand Down Expand Up @@ -518,9 +519,10 @@ CGO MEMORY | block cache | memtables
0B | 0B | 0B | 0B | 0B | 0B

COMPACTIONS
estimated debt | in progress | cancelled | failed | problem spans
------------------+-------------------+-------------------+-------------------+-------------------
3.8KB | 0 (0B) | 0 (0B) | 0 | 0
| blob rewrites
est. debt | in progress | cancelled | failed | problem spans | read | written
--------------+---------------+------------+----------+------------------+------------+-----------
3.8KB | 0 (0B) | 0 (0B) | 0 | 0 | 0B | 0B

KEYS
range keys | tombstones | missized tombstones | point dels | range dels
Expand Down
7 changes: 4 additions & 3 deletions testdata/ingest
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Original file line number Diff line number Diff line change
Expand Up @@ -93,9 +93,10 @@ CGO MEMORY | block cache | memtables
0B | 0B | 0B | 0B | 0B | 0B

COMPACTIONS
estimated debt | in progress | cancelled | failed | problem spans
------------------+-------------------+-------------------+-------------------+-------------------
0B | 0 (0B) | 0 (0B) | 0 | 0
| blob rewrites
est. debt | in progress | cancelled | failed | problem spans | read | written
--------------+---------------+------------+----------+------------------+------------+-----------
0B | 0 (0B) | 0 (0B) | 0 | 0 | 0B | 0B

KEYS
range keys | tombstones | missized tombstones | point dels | range dels
Expand Down
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