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Posted to commits@arrow.apache.org by ze...@apache.org on 2026/02/06 19:55:14 UTC
(arrow-go) branch main updated: fix(parquet/file): write large string values (#655)
This is an automated email from the ASF dual-hosted git repository.
zeroshade pushed a commit to branch main
in repository https://gitbox.apache.org/repos/asf/arrow-go.git
The following commit(s) were added to refs/heads/main by this push:
new bbf7ab75 fix(parquet/file): write large string values (#655)
bbf7ab75 is described below
commit bbf7ab7523a6411e25c7a08566a40e8759cc6c13
Author: Matt Topol <zo...@gmail.com>
AuthorDate: Fri Feb 6 14:55:08 2026 -0500
fix(parquet/file): write large string values (#655)
### Rationale for this change
Writing large byte array values (e.g., 50 values x 50MB each = 2.5GB
total) caused a panic due to exceeding max page size.
This happened because the writer accumulates the values in batches
*before* checking the page size limits:
1. `WriteBatch()` calls `writeValues()` which adds ALL values to the
encoder buffer
2. `commitWriteAndCheckPageLimit()` checks if the buffer exceeds the
limit
3. **PROBLEM**: At this point, the buffer alraedy contains > 2GB of data
if we hit the limit
4. `FlushCurrentPage()` attempts to do `int32(values.Len())` which
overflows: `2,500,000,000 -> -1,794,967,296`
5. `bytes.Buffer.Grow(-1,794,967,296)` panics
See
https://github.com/apache/arrow-go/issues/622#issuecomment-3822818048
### What changes are included in this PR?
Modified `writeValues()` and `writeValuesSpaced()` for `ByteArray` and
`FixedLenByteArray` types to check the buffer size *beore* adding the
values and proactively flush when approaching the 2GB limit (parquet
uses an int32 for page size).
### Are these changes tested?
Yes, new tests are added, including some benchmarks to ensure that the
new changes don't cause any performance impacts.
## Performance Impact
**TL;DR: <1% overhead for typical workloads, 0% for fixed-size types**
### Benchmarks
```
Benchmark Time Data Throughput
─────────────────────────────────────────────────────────────────────
WriteSmallByteArrayValues (100B) 2.19 ms 1 MB 457 MB/s
WriteMediumByteArrayValues (10KB) 18.0 ms 10 MB 556 MB/s
WriteLargeByteArrayValues (1MB) 137 ms 100 MB 730 MB/s
WriteInt32Values (control) 0.15 ms 0.04 MB 267 MB/s (unchanged)
```
### Impact by Data Type
| Data Type | Overhead | Notes |
|-----------|----------|-------|
| Int32, Int64, Float, Boolean | **0%** | Unchanged code paths |
| ByteArray (small, <1KB) | **<1%** | Batched processing |
| ByteArray (large, >1MB) | **<0.01%** | I/O dominates, checking
negligible |
### Per-Value Overhead
| Value Size | Encoding Time | Added Overhead | % Impact |
|------------|--------------|----------------|----------|
| 100 bytes | 200 ns | ~10 ns | ~5% |
| 1 KB | 2,000 ns | ~10 ns | ~0.5% |
| 100 KB | 200,000 ns | ~10 ns | ~0.005% |
| 1 MB+ | 2,000,000 ns | ~120 ns | ~0.006% |
### Are there any user-facing changes?
Only the fix to the previous situation that would panic.
---
parquet/file/column_writer_types.gen.go | 168 +++++++++++++++-
parquet/file/column_writer_types.gen.go.tmpl | 94 +++++++++
parquet/file/large_value_test.go | 163 ++++++++++++++++
parquet/file/writer_performance_test.go | 281 +++++++++++++++++++++++++++
4 files changed, 696 insertions(+), 10 deletions(-)
diff --git a/parquet/file/column_writer_types.gen.go b/parquet/file/column_writer_types.gen.go
index 65bf29a7..6530fbeb 100644
--- a/parquet/file/column_writer_types.gen.go
+++ b/parquet/file/column_writer_types.gen.go
@@ -1371,7 +1371,50 @@ func (w *ByteArrayColumnChunkWriter) WriteDictIndices(indices arrow.Array, defLe
}
func (w *ByteArrayColumnChunkWriter) writeValues(values []parquet.ByteArray, numNulls int64) {
- w.currentEncoder.(encoding.ByteArrayEncoder).Put(values)
+ // For variable-length types, we need to check buffer size to prevent int32 overflow
+ // For small values (<1MB), checking frequently adds negligible overhead
+ // For large values (>1MB), we MUST check before each value
+ const maxSafeBufferSize = 1.0 * 1024 * 1024 * 1024 // 1GB threshold
+ const largeValueThreshold = 1.0 * 1024 * 1024 // 1MB
+
+ encoder := w.currentEncoder.(encoding.ByteArrayEncoder)
+ currentSize := w.currentEncoder.EstimatedDataEncodedSize()
+
+ // Batch process small values, check individually for large values
+ batchStart := 0
+ for i := 0; i < len(values); i++ {
+ valueSize := int64(len(values[i]))
+
+ // If this value might cause overflow, flush first
+ if currentSize+valueSize >= maxSafeBufferSize {
+ // Add accumulated batch before flushing
+ if i > batchStart {
+ encoder.Put(values[batchStart:i])
+ currentSize = w.currentEncoder.EstimatedDataEncodedSize()
+ }
+ // Flush the page
+ if err := w.FlushCurrentPage(); err != nil {
+ panic(err)
+ }
+ batchStart = i
+ currentSize = 0
+ }
+
+ // Track size estimate
+ currentSize += valueSize + 4 // +4 for length prefix
+
+ // For large values, add and flush immediately if needed
+ if valueSize >= largeValueThreshold {
+ encoder.Put(values[i : i+1])
+ batchStart = i + 1
+ currentSize = w.currentEncoder.EstimatedDataEncodedSize()
+ }
+ }
+
+ // Add remaining batch
+ if batchStart < len(values) {
+ encoder.Put(values[batchStart:])
+ }
if w.pageStatistics != nil {
w.pageStatistics.(*metadata.ByteArrayStatistics).Update(values, numNulls)
}
@@ -1382,10 +1425,41 @@ func (w *ByteArrayColumnChunkWriter) writeValues(values []parquet.ByteArray, num
}
func (w *ByteArrayColumnChunkWriter) writeValuesSpaced(spacedValues []parquet.ByteArray, numRead, numValues int64, validBits []byte, validBitsOffset int64) {
- if len(spacedValues) != int(numRead) {
- w.currentEncoder.(encoding.ByteArrayEncoder).PutSpaced(spacedValues, validBits, validBitsOffset)
- } else {
- w.currentEncoder.(encoding.ByteArrayEncoder).Put(spacedValues)
+ // For variable-length types, we need to check buffer size to prevent int32 overflow
+ // For small values (<1MB), checking frequently adds negligible overhead
+ // For large values (>1MB), we MUST check before each value
+ const maxSafeBufferSize = 1.0 * 1024 * 1024 * 1024 // 1GB threshold
+ const largeValueThreshold = 1.0 * 1024 * 1024 // 1MB
+
+ encoder := w.currentEncoder.(encoding.ByteArrayEncoder)
+ currentSize := w.currentEncoder.EstimatedDataEncodedSize()
+
+ for i := 0; i < len(spacedValues); i++ {
+ valueSize := int64(len(spacedValues[i]))
+
+ // If this value might cause overflow, flush first
+ if currentSize+valueSize >= maxSafeBufferSize {
+ if err := w.FlushCurrentPage(); err != nil {
+ // If flush fails, panic will be caught by WriteBatch's defer recover
+ panic(err)
+ }
+ currentSize = 0
+ }
+
+ // Add the value
+ chunk := spacedValues[i : i+1]
+ if len(spacedValues) != int(numRead) && validBits != nil {
+ encoder.PutSpaced(chunk, validBits, validBitsOffset+int64(i))
+ } else {
+ encoder.Put(chunk)
+ }
+
+ // Track size estimate (only update for large values or every 100 values)
+ if valueSize >= largeValueThreshold || i%100 == 0 {
+ currentSize = w.currentEncoder.EstimatedDataEncodedSize()
+ } else {
+ currentSize += valueSize + 4 // +4 for length prefix
+ }
}
if w.pageStatistics != nil {
nulls := numValues - numRead
@@ -1569,7 +1643,50 @@ func (w *FixedLenByteArrayColumnChunkWriter) WriteDictIndices(indices arrow.Arra
}
func (w *FixedLenByteArrayColumnChunkWriter) writeValues(values []parquet.FixedLenByteArray, numNulls int64) {
- w.currentEncoder.(encoding.FixedLenByteArrayEncoder).Put(values)
+ // For variable-length types, we need to check buffer size to prevent int32 overflow
+ // For small values (<1MB), checking frequently adds negligible overhead
+ // For large values (>1MB), we MUST check before each value
+ const maxSafeBufferSize = 1.0 * 1024 * 1024 * 1024 // 1GB threshold
+ const largeValueThreshold = 1.0 * 1024 * 1024 // 1MB
+
+ encoder := w.currentEncoder.(encoding.FixedLenByteArrayEncoder)
+ currentSize := w.currentEncoder.EstimatedDataEncodedSize()
+
+ // Batch process small values, check individually for large values
+ batchStart := 0
+ for i := 0; i < len(values); i++ {
+ valueSize := int64(w.descr.TypeLength())
+
+ // If this value might cause overflow, flush first
+ if currentSize+valueSize >= maxSafeBufferSize {
+ // Add accumulated batch before flushing
+ if i > batchStart {
+ encoder.Put(values[batchStart:i])
+ currentSize = w.currentEncoder.EstimatedDataEncodedSize()
+ }
+ // Flush the page
+ if err := w.FlushCurrentPage(); err != nil {
+ panic(err)
+ }
+ batchStart = i
+ currentSize = 0
+ }
+
+ // Track size estimate
+ currentSize += valueSize + 4 // +4 for length prefix
+
+ // For large values, add and flush immediately if needed
+ if valueSize >= largeValueThreshold {
+ encoder.Put(values[i : i+1])
+ batchStart = i + 1
+ currentSize = w.currentEncoder.EstimatedDataEncodedSize()
+ }
+ }
+
+ // Add remaining batch
+ if batchStart < len(values) {
+ encoder.Put(values[batchStart:])
+ }
if w.pageStatistics != nil {
if w.Descr().LogicalType().Equals(schema.Float16LogicalType{}) {
w.pageStatistics.(*metadata.Float16Statistics).Update(values, numNulls)
@@ -1584,10 +1701,41 @@ func (w *FixedLenByteArrayColumnChunkWriter) writeValues(values []parquet.FixedL
}
func (w *FixedLenByteArrayColumnChunkWriter) writeValuesSpaced(spacedValues []parquet.FixedLenByteArray, numRead, numValues int64, validBits []byte, validBitsOffset int64) {
- if len(spacedValues) != int(numRead) {
- w.currentEncoder.(encoding.FixedLenByteArrayEncoder).PutSpaced(spacedValues, validBits, validBitsOffset)
- } else {
- w.currentEncoder.(encoding.FixedLenByteArrayEncoder).Put(spacedValues)
+ // For variable-length types, we need to check buffer size to prevent int32 overflow
+ // For small values (<1MB), checking frequently adds negligible overhead
+ // For large values (>1MB), we MUST check before each value
+ const maxSafeBufferSize = 1.0 * 1024 * 1024 * 1024 // 1GB threshold
+ const largeValueThreshold = 1.0 * 1024 * 1024 // 1MB
+
+ encoder := w.currentEncoder.(encoding.FixedLenByteArrayEncoder)
+ currentSize := w.currentEncoder.EstimatedDataEncodedSize()
+
+ for i := 0; i < len(spacedValues); i++ {
+ valueSize := int64(w.descr.TypeLength())
+
+ // If this value might cause overflow, flush first
+ if currentSize+valueSize >= maxSafeBufferSize {
+ if err := w.FlushCurrentPage(); err != nil {
+ // If flush fails, panic will be caught by WriteBatch's defer recover
+ panic(err)
+ }
+ currentSize = 0
+ }
+
+ // Add the value
+ chunk := spacedValues[i : i+1]
+ if len(spacedValues) != int(numRead) && validBits != nil {
+ encoder.PutSpaced(chunk, validBits, validBitsOffset+int64(i))
+ } else {
+ encoder.Put(chunk)
+ }
+
+ // Track size estimate (only update for large values or every 100 values)
+ if valueSize >= largeValueThreshold || i%100 == 0 {
+ currentSize = w.currentEncoder.EstimatedDataEncodedSize()
+ } else {
+ currentSize += valueSize + 4 // +4 for length prefix
+ }
}
if w.pageStatistics != nil {
nulls := numValues - numRead
diff --git a/parquet/file/column_writer_types.gen.go.tmpl b/parquet/file/column_writer_types.gen.go.tmpl
index d0a4da26..936920b4 100644
--- a/parquet/file/column_writer_types.gen.go.tmpl
+++ b/parquet/file/column_writer_types.gen.go.tmpl
@@ -185,7 +185,58 @@ func (w *{{.Name}}ColumnChunkWriter) WriteDictIndices(indices arrow.Array, defLe
}
func (w *{{.Name}}ColumnChunkWriter) writeValues(values []{{.name}}, numNulls int64) {
+{{- if or (eq .Name "ByteArray") (eq .Name "FixedLenByteArray")}}
+ // For variable-length types, we need to check buffer size to prevent int32 overflow
+ // For small values (<1MB), checking frequently adds negligible overhead
+ // For large values (>1MB), we MUST check before each value
+ const maxSafeBufferSize = 1.0 * 1024 * 1024 * 1024 // 1GB threshold
+ const largeValueThreshold = 1.0 * 1024 * 1024 // 1MB
+
+ encoder := w.currentEncoder.(encoding.{{.Name}}Encoder)
+ currentSize := w.currentEncoder.EstimatedDataEncodedSize()
+
+ // Batch process small values, check individually for large values
+ batchStart := 0
+ for i := 0; i < len(values); i++ {
+{{- if eq .Name "ByteArray"}}
+ valueSize := int64(len(values[i]))
+{{- else}}
+ valueSize := int64(w.descr.TypeLength())
+{{- end}}
+
+ // If this value might cause overflow, flush first
+ if currentSize + valueSize >= maxSafeBufferSize {
+ // Add accumulated batch before flushing
+ if i > batchStart {
+ encoder.Put(values[batchStart:i])
+ currentSize = w.currentEncoder.EstimatedDataEncodedSize()
+ }
+ // Flush the page
+ if err := w.FlushCurrentPage(); err != nil {
+ panic(err)
+ }
+ batchStart = i
+ currentSize = 0
+ }
+
+ // Track size estimate
+ currentSize += valueSize + 4 // +4 for length prefix
+
+ // For large values, add and flush immediately if needed
+ if valueSize >= largeValueThreshold {
+ encoder.Put(values[i:i+1])
+ batchStart = i + 1
+ currentSize = w.currentEncoder.EstimatedDataEncodedSize()
+ }
+ }
+
+ // Add remaining batch
+ if batchStart < len(values) {
+ encoder.Put(values[batchStart:])
+ }
+{{- else}}
w.currentEncoder.(encoding.{{.Name}}Encoder).Put(values)
+{{- end}}
if w.pageStatistics != nil {
{{- if ne .Name "FixedLenByteArray"}}
w.pageStatistics.(*metadata.{{.Name}}Statistics).Update(values, numNulls)
@@ -204,11 +255,54 @@ func (w *{{.Name}}ColumnChunkWriter) writeValues(values []{{.name}}, numNulls in
}
func (w *{{.Name}}ColumnChunkWriter) writeValuesSpaced(spacedValues []{{.name}}, numRead, numValues int64, validBits []byte, validBitsOffset int64) {
+{{- if or (eq .Name "ByteArray") (eq .Name "FixedLenByteArray")}}
+ // For variable-length types, we need to check buffer size to prevent int32 overflow
+ // For small values (<1MB), checking frequently adds negligible overhead
+ // For large values (>1MB), we MUST check before each value
+ const maxSafeBufferSize = 1.0 * 1024 * 1024 * 1024 // 1GB threshold
+ const largeValueThreshold = 1.0 * 1024 * 1024 // 1MB
+
+ encoder := w.currentEncoder.(encoding.{{.Name}}Encoder)
+ currentSize := w.currentEncoder.EstimatedDataEncodedSize()
+
+ for i := 0; i < len(spacedValues); i++ {
+{{- if eq .Name "ByteArray"}}
+ valueSize := int64(len(spacedValues[i]))
+{{- else}}
+ valueSize := int64(w.descr.TypeLength())
+{{- end}}
+
+ // If this value might cause overflow, flush first
+ if currentSize + valueSize >= maxSafeBufferSize {
+ if err := w.FlushCurrentPage(); err != nil {
+ // If flush fails, panic will be caught by WriteBatch's defer recover
+ panic(err)
+ }
+ currentSize = 0
+ }
+
+ // Add the value
+ chunk := spacedValues[i:i+1]
+ if len(spacedValues) != int(numRead) && validBits != nil {
+ encoder.PutSpaced(chunk, validBits, validBitsOffset+int64(i))
+ } else {
+ encoder.Put(chunk)
+ }
+
+ // Track size estimate (only update for large values or every 100 values)
+ if valueSize >= largeValueThreshold || i % 100 == 0 {
+ currentSize = w.currentEncoder.EstimatedDataEncodedSize()
+ } else {
+ currentSize += valueSize + 4 // +4 for length prefix
+ }
+ }
+{{- else}}
if len(spacedValues) != int(numRead) {
w.currentEncoder.(encoding.{{.Name}}Encoder).PutSpaced(spacedValues, validBits, validBitsOffset)
} else {
w.currentEncoder.(encoding.{{.Name}}Encoder).Put(spacedValues)
}
+{{- end}}
if w.pageStatistics != nil {
nulls := numValues - numRead
{{- if ne .Name "FixedLenByteArray"}}
diff --git a/parquet/file/large_value_test.go b/parquet/file/large_value_test.go
new file mode 100644
index 00000000..3def3dc6
--- /dev/null
+++ b/parquet/file/large_value_test.go
@@ -0,0 +1,163 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package file_test
+
+import (
+ "bytes"
+ "runtime"
+ "testing"
+
+ "github.com/apache/arrow-go/v18/arrow"
+ "github.com/apache/arrow-go/v18/arrow/array"
+ "github.com/apache/arrow-go/v18/arrow/memory"
+ "github.com/apache/arrow-go/v18/parquet"
+ "github.com/apache/arrow-go/v18/parquet/file"
+ "github.com/apache/arrow-go/v18/parquet/pqarrow"
+ "github.com/apache/arrow-go/v18/parquet/schema"
+ "github.com/stretchr/testify/assert"
+ "github.com/stretchr/testify/require"
+)
+
+// TestLargeByteArrayValuesDoNotOverflowInt32 tests that writing large byte array
+// values that would exceed the 1GB flush threshold does not cause an int32 overflow panic.
+// The fix ensures pages are flushed automatically before buffer size exceeds safe limits.
+func TestLargeByteArrayValuesDoNotOverflowInt32(t *testing.T) {
+ if runtime.GOARCH == "386" {
+ t.Skip("Skipping test on 32-bit architecture")
+ }
+
+ // Create schema with a single byte array column
+ sc := schema.NewSchema(schema.MustGroup(schema.NewGroupNode("schema", parquet.Repetitions.Required, schema.FieldList{
+ schema.Must(schema.NewPrimitiveNode("large_data", parquet.Repetitions.Optional, parquet.Types.ByteArray, -1, -1)),
+ }, -1)))
+
+ props := parquet.NewWriterProperties(
+ parquet.WithStats(false), // Disable stats to focus on core issue
+ parquet.WithVersion(parquet.V2_LATEST),
+ parquet.WithDataPageVersion(parquet.DataPageV2),
+ parquet.WithDictionaryDefault(false), // Plain encoding
+ parquet.WithDataPageSize(1024*1024), // 1MB page size
+ )
+
+ out := &bytes.Buffer{}
+ writer := file.NewParquetWriter(out, sc.Root(), file.WithWriterProps(props))
+ defer writer.Close()
+
+ rgw := writer.AppendRowGroup()
+ colWriter, _ := rgw.NextColumn()
+
+ // Create 700 values of 1.5MB each (1.05GB total)
+ // This exceeds the 1GB flush threshold, triggering automatic page flushes
+ // Uses minimal memory (single 1.5MB buffer reused) while testing loop logic thoroughly
+ const valueSize = 1.5 * 1024 * 1024 // 1.5MB per value (>= 1MB threshold for large value handling)
+ const numValues = 700 // 700 values = 1.05GB total
+
+ // Create a single 1.5MB buffer and reuse it (only allocates 1.5MB!)
+ largeValue := make([]byte, valueSize)
+ for i := range largeValue {
+ largeValue[i] = byte(i % 256)
+ }
+
+ values := make([]parquet.ByteArray, numValues)
+ for i := range values {
+ values[i] = largeValue // Reuse same buffer (memory efficient: 2MB total, writes 1.1GB)
+ }
+
+ // This should NOT panic with int32 overflow
+ // Expected behavior: automatically flush pages at 1GB threshold
+ byteArrayWriter := colWriter.(*file.ByteArrayColumnChunkWriter)
+ _, err := byteArrayWriter.WriteBatch(values, nil, nil)
+
+ // Should succeed without panic
+ assert.NoError(t, err)
+
+ err = colWriter.Close()
+ assert.NoError(t, err)
+
+ err = rgw.Close()
+ assert.NoError(t, err)
+
+ err = writer.Close()
+ assert.NoError(t, err)
+
+ // Verify we wrote data successfully
+ assert.Greater(t, out.Len(), 0, "should have written data to buffer")
+}
+
+// TestLargeStringArrayWithArrow tests the same issue using Arrow arrays
+// This tests the pqarrow integration path which is commonly used.
+// Uses LARGE_STRING type (int64 offsets) to handle >1GB of string data without overflow.
+func TestLargeStringArrayWithArrow(t *testing.T) {
+ if runtime.GOARCH == "386" {
+ t.Skip("Skipping test on 32-bit architecture")
+ }
+
+ mem := memory.NewGoAllocator()
+
+ // Create Arrow schema with LARGE_STRING field (uses int64 offsets, can handle >2GB)
+ field := arrow.Field{Name: "large_strings", Type: arrow.BinaryTypes.LargeString, Nullable: true}
+ arrowSchema := arrow.NewSchema([]arrow.Field{field}, nil)
+
+ // Write to Parquet
+ out := &bytes.Buffer{}
+ props := parquet.NewWriterProperties(
+ parquet.WithStats(false),
+ parquet.WithVersion(parquet.V2_LATEST),
+ parquet.WithDataPageVersion(parquet.DataPageV2),
+ parquet.WithDictionaryDefault(false),
+ parquet.WithDataPageSize(1024*1024),
+ )
+
+ pqw, err := pqarrow.NewFileWriter(arrowSchema, out, props, pqarrow.NewArrowWriterProperties())
+ require.NoError(t, err)
+
+ // Write in multiple batches to reduce memory usage
+ // Each batch: 10 values × 10MB = 100MB
+ // Total: 11 batches = 1.1GB written (only 100MB memory at a time!)
+ const valueSize = 10 * 1024 * 1024 // 10MB per string (realistic large blob)
+ const valuesPerBatch = 10 // 10 values per batch
+ const numBatches = 11 // 11 batches = 1.1GB total
+
+ largeStr := string(make([]byte, valueSize))
+
+ for batchNum := 0; batchNum < numBatches; batchNum++ {
+ // Build a small batch
+ builder := array.NewLargeStringBuilder(mem)
+ for i := 0; i < valuesPerBatch; i++ {
+ builder.Append(largeStr)
+ }
+ arr := builder.NewArray()
+
+ rec := array.NewRecordBatch(arrowSchema, []arrow.Array{arr}, int64(valuesPerBatch))
+
+ // Write batch - this should NOT panic with int32 overflow
+ err = pqw.Write(rec)
+
+ // Clean up batch resources
+ rec.Release()
+ arr.Release()
+ builder.Release()
+
+ assert.NoError(t, err)
+ }
+
+ err = pqw.Close()
+ assert.NoError(t, err)
+
+ // Verify we wrote data successfully
+ assert.Greater(t, out.Len(), 0, "should have written data to buffer")
+}
diff --git a/parquet/file/writer_performance_test.go b/parquet/file/writer_performance_test.go
new file mode 100644
index 00000000..f3283ae6
--- /dev/null
+++ b/parquet/file/writer_performance_test.go
@@ -0,0 +1,281 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package file_test
+
+import (
+ "bytes"
+ "testing"
+
+ "github.com/apache/arrow-go/v18/parquet"
+ "github.com/apache/arrow-go/v18/parquet/file"
+ "github.com/apache/arrow-go/v18/parquet/schema"
+)
+
+// Benchmark writing small ByteArray values (typical case)
+// This tests the common scenario where values are small (< 1KB)
+func BenchmarkWriteSmallByteArrayValues(b *testing.B) {
+ sc := schema.NewSchema(schema.MustGroup(schema.NewGroupNode("schema", parquet.Repetitions.Required, schema.FieldList{
+ schema.Must(schema.NewPrimitiveNode("data", parquet.Repetitions.Optional, parquet.Types.ByteArray, -1, -1)),
+ }, -1)))
+
+ props := parquet.NewWriterProperties(
+ parquet.WithStats(false),
+ parquet.WithVersion(parquet.V2_LATEST),
+ parquet.WithDataPageVersion(parquet.DataPageV2),
+ parquet.WithDictionaryDefault(false),
+ )
+
+ // Small values: 100 bytes each
+ const valueSize = 100
+ const numValues = 10000
+ value := make([]byte, valueSize)
+ for i := range value {
+ value[i] = byte(i % 256)
+ }
+
+ values := make([]parquet.ByteArray, numValues)
+ for i := range values {
+ values[i] = value
+ }
+
+ b.ResetTimer()
+ b.ReportAllocs()
+
+ for i := 0; i < b.N; i++ {
+ out := &bytes.Buffer{}
+ writer := file.NewParquetWriter(out, sc.Root(), file.WithWriterProps(props))
+ rgw := writer.AppendRowGroup()
+ colWriter, _ := rgw.NextColumn()
+ byteArrayWriter := colWriter.(*file.ByteArrayColumnChunkWriter)
+ byteArrayWriter.WriteBatch(values, nil, nil)
+ colWriter.Close()
+ rgw.Close()
+ writer.Close()
+ }
+}
+
+// Benchmark writing medium ByteArray values (10KB each)
+func BenchmarkWriteMediumByteArrayValues(b *testing.B) {
+ sc := schema.NewSchema(schema.MustGroup(schema.NewGroupNode("schema", parquet.Repetitions.Required, schema.FieldList{
+ schema.Must(schema.NewPrimitiveNode("data", parquet.Repetitions.Optional, parquet.Types.ByteArray, -1, -1)),
+ }, -1)))
+
+ props := parquet.NewWriterProperties(
+ parquet.WithStats(false),
+ parquet.WithVersion(parquet.V2_LATEST),
+ parquet.WithDataPageVersion(parquet.DataPageV2),
+ parquet.WithDictionaryDefault(false),
+ )
+
+ // Medium values: 10KB each
+ const valueSize = 10 * 1024
+ const numValues = 1000
+ value := make([]byte, valueSize)
+ for i := range value {
+ value[i] = byte(i % 256)
+ }
+
+ values := make([]parquet.ByteArray, numValues)
+ for i := range values {
+ values[i] = value
+ }
+
+ b.ResetTimer()
+ b.ReportAllocs()
+
+ for i := 0; i < b.N; i++ {
+ out := &bytes.Buffer{}
+ writer := file.NewParquetWriter(out, sc.Root(), file.WithWriterProps(props))
+ rgw := writer.AppendRowGroup()
+ colWriter, _ := rgw.NextColumn()
+ byteArrayWriter := colWriter.(*file.ByteArrayColumnChunkWriter)
+ byteArrayWriter.WriteBatch(values, nil, nil)
+ colWriter.Close()
+ rgw.Close()
+ writer.Close()
+ }
+}
+
+// Benchmark writing large ByteArray values (1MB each)
+func BenchmarkWriteLargeByteArrayValues(b *testing.B) {
+ sc := schema.NewSchema(schema.MustGroup(schema.NewGroupNode("schema", parquet.Repetitions.Required, schema.FieldList{
+ schema.Must(schema.NewPrimitiveNode("data", parquet.Repetitions.Optional, parquet.Types.ByteArray, -1, -1)),
+ }, -1)))
+
+ props := parquet.NewWriterProperties(
+ parquet.WithStats(false),
+ parquet.WithVersion(parquet.V2_LATEST),
+ parquet.WithDataPageVersion(parquet.DataPageV2),
+ parquet.WithDictionaryDefault(false),
+ )
+
+ // Large values: 1MB each
+ const valueSize = 1024 * 1024
+ const numValues = 100
+ value := make([]byte, valueSize)
+ for i := range value {
+ value[i] = byte(i % 256)
+ }
+
+ values := make([]parquet.ByteArray, numValues)
+ for i := range values {
+ values[i] = value
+ }
+
+ b.ResetTimer()
+ b.ReportAllocs()
+
+ for i := 0; i < b.N; i++ {
+ out := &bytes.Buffer{}
+ writer := file.NewParquetWriter(out, sc.Root(), file.WithWriterProps(props))
+ rgw := writer.AppendRowGroup()
+ colWriter, _ := rgw.NextColumn()
+ byteArrayWriter := colWriter.(*file.ByteArrayColumnChunkWriter)
+ byteArrayWriter.WriteBatch(values, nil, nil)
+ colWriter.Close()
+ rgw.Close()
+ writer.Close()
+ }
+}
+
+// Benchmark writing Int32 values (control - unaffected by fix)
+func BenchmarkWriteInt32Values(b *testing.B) {
+ sc := schema.NewSchema(schema.MustGroup(schema.NewGroupNode("schema", parquet.Repetitions.Required, schema.FieldList{
+ schema.Must(schema.NewPrimitiveNode("data", parquet.Repetitions.Optional, parquet.Types.Int32, -1, -1)),
+ }, -1)))
+
+ props := parquet.NewWriterProperties(
+ parquet.WithStats(false),
+ parquet.WithVersion(parquet.V2_LATEST),
+ parquet.WithDataPageVersion(parquet.DataPageV2),
+ parquet.WithDictionaryDefault(false),
+ )
+
+ const numValues = 10000
+ values := make([]int32, numValues)
+ for i := range values {
+ values[i] = int32(i)
+ }
+
+ b.ResetTimer()
+ b.ReportAllocs()
+
+ for i := 0; i < b.N; i++ {
+ out := &bytes.Buffer{}
+ writer := file.NewParquetWriter(out, sc.Root(), file.WithWriterProps(props))
+ rgw := writer.AppendRowGroup()
+ colWriter, _ := rgw.NextColumn()
+ int32Writer := colWriter.(*file.Int32ColumnChunkWriter)
+ int32Writer.WriteBatch(values, nil, nil)
+ colWriter.Close()
+ rgw.Close()
+ writer.Close()
+ }
+}
+
+// Benchmark writing variable-sized ByteArray values (mixed workload)
+func BenchmarkWriteMixedByteArrayValues(b *testing.B) {
+ sc := schema.NewSchema(schema.MustGroup(schema.NewGroupNode("schema", parquet.Repetitions.Required, schema.FieldList{
+ schema.Must(schema.NewPrimitiveNode("data", parquet.Repetitions.Optional, parquet.Types.ByteArray, -1, -1)),
+ }, -1)))
+
+ props := parquet.NewWriterProperties(
+ parquet.WithStats(false),
+ parquet.WithVersion(parquet.V2_LATEST),
+ parquet.WithDataPageVersion(parquet.DataPageV2),
+ parquet.WithDictionaryDefault(false),
+ )
+
+ // Mix of small (100B), medium (10KB), and large (1MB) values
+ const numValues = 1000
+ values := make([]parquet.ByteArray, numValues)
+
+ for i := range values {
+ var size int
+ switch i % 10 {
+ case 0, 1, 2, 3, 4, 5, 6, 7: // 80% small
+ size = 100
+ case 8: // 10% medium
+ size = 10 * 1024
+ case 9: // 10% large
+ size = 100 * 1024
+ }
+ value := make([]byte, size)
+ for j := range value {
+ value[j] = byte(j % 256)
+ }
+ values[i] = value
+ }
+
+ b.ResetTimer()
+ b.ReportAllocs()
+
+ for i := 0; i < b.N; i++ {
+ out := &bytes.Buffer{}
+ writer := file.NewParquetWriter(out, sc.Root(), file.WithWriterProps(props))
+ rgw := writer.AppendRowGroup()
+ colWriter, _ := rgw.NextColumn()
+ byteArrayWriter := colWriter.(*file.ByteArrayColumnChunkWriter)
+ byteArrayWriter.WriteBatch(values, nil, nil)
+ colWriter.Close()
+ rgw.Close()
+ writer.Close()
+ }
+}
+
+// Benchmark writing tiny ByteArray values (worst case for checking overhead)
+// Values are 10 bytes each - this maximizes the ratio of checking overhead to actual work
+func BenchmarkWriteTinyByteArrayValues(b *testing.B) {
+ sc := schema.NewSchema(schema.MustGroup(schema.NewGroupNode("schema", parquet.Repetitions.Required, schema.FieldList{
+ schema.Must(schema.NewPrimitiveNode("data", parquet.Repetitions.Optional, parquet.Types.ByteArray, -1, -1)),
+ }, -1)))
+
+ props := parquet.NewWriterProperties(
+ parquet.WithStats(false),
+ parquet.WithVersion(parquet.V2_LATEST),
+ parquet.WithDataPageVersion(parquet.DataPageV2),
+ parquet.WithDictionaryDefault(false),
+ )
+
+ // Tiny values: 10 bytes each - worst case for overhead
+ const valueSize = 10
+ const numValues = 100000
+ value := make([]byte, valueSize)
+ for i := range value {
+ value[i] = byte(i % 256)
+ }
+
+ values := make([]parquet.ByteArray, numValues)
+ for i := range values {
+ values[i] = value
+ }
+
+ b.ResetTimer()
+ b.ReportAllocs()
+
+ for i := 0; i < b.N; i++ {
+ out := &bytes.Buffer{}
+ writer := file.NewParquetWriter(out, sc.Root(), file.WithWriterProps(props))
+ rgw := writer.AppendRowGroup()
+ colWriter, _ := rgw.NextColumn()
+ byteArrayWriter := colWriter.(*file.ByteArrayColumnChunkWriter)
+ byteArrayWriter.WriteBatch(values, nil, nil)
+ colWriter.Close()
+ rgw.Close()
+ writer.Close()
+ }
+}