perf: less alloc

[cuiweixie]

Summary by CodeRabbit

• Performance
  • Optimized internal byte conversion in pruning operations to reduce memory allocations and improve throughput, especially on large datasets.
• Refactor
  • Streamlined implementation to preallocate exact buffer sizes, improving efficiency without altering behavior or outputs.

[cuiweixie]

#25356
@aljo242

[coderabbitai]

📝 Walkthrough

Walkthrough

Refactors int64SliceToBytes in store/pruning/manager.go to preallocate the exact output byte slice and write each int64’s big-endian bytes directly at computed offsets, replacing per-element append-based construction. No public APIs changed; behavior remains the same.

Changes

Cohort / File(s)	Summary
Pruning serialization optimization store/pruning/manager.go	Rewrote int64 slice-to-bytes conversion to preallocate len*8 buffer and fill via offset indexing (i<<3) with big-endian writes, removing per-iteration appends and reducing allocations; no semantic or control-flow changes.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Pre-merge checks and finishing touches

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title Check	✅ Passed	The title "refactor: less alloc" clearly indicates the PR's main intent—reducing allocations—which matches the refactor of int64SliceToBytes described in the changeset; it is concise and related to the primary change, though slightly informal and not function-specific.

✨ Finishing touches

• 📝 Generate Docstrings

🧪 Generate unit tests

• Create PR with unit tests
• Post copyable unit tests in a comment

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[coderabbitai]

Actionable comments posted: 0

🧹 Nitpick comments (2)

store/pruning/manager.go (2)

227-231: Allocation-free encoding is correct; minor readability tweak suggested

Change reduces allocations and keeps endianness consistent. Consider making the 8‑byte window explicit and using multiplication for clarity.

 func int64SliceToBytes(slice ...int64) []byte {
-	bz := make([]byte, len(slice)*8)
-	for i, ph := range slice {
-		binary.BigEndian.PutUint64(bz[i<<3:], uint64(ph))
-	}
+	bz := make([]byte, len(slice)*8)
+	for i, ph := range slice {
+		off := i * 8 // clearer than i<<3
+		binary.BigEndian.PutUint64(bz[off:off+8], uint64(ph))
+	}
 	return bz
 }

---

226-231: Add int64ToBytes(int64) and use it from storePruningSnapshotHeight

Implement a helper that encodes a single int64 (no variadic allocation) and call it from store/pruning/manager.go (storePruningSnapshotHeight — currently calls int64SliceToBytes at line 199); keep int64SliceToBytes(...) for multi-value callers (store/pruning/manager_test.go at line 439).

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

Knowledge base: Disabled due to Reviews -> Disable Knowledge Base setting

📥 Commits

Reviewing files that changed from the base of the PR and between 9171179 and 7723a56.

📒 Files selected for processing (1)

• store/pruning/manager.go (1 hunks)

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (1)

• GitHub Check: Summary

[aljo242]

is there a test that validates this change is ok?

[cuiweixie]

here will test.

cosmos-sdk/store/pruning/manager_test.go

Line 439 in 97c0bd8

err = db.Set(pruneSnapshotHeightsKey, int64SliceToBytes(tc.getFlushedPruningSnapshotHeights()...))

package main

import (
	"bytes"
	"encoding/binary"
	"testing"
)

func int64SliceToBytesV1(slice ...int64) []byte {
	bz := make([]byte, 0, len(slice)*8)
	for _, ph := range slice {
		buf := make([]byte, 8)
		binary.BigEndian.PutUint64(buf, uint64(ph))
		bz = append(bz, buf...)
	}
	return bz
}

func int64SliceToBytesV2(slice ...int64) []byte {
	bz := make([]byte, len(slice)*8)
	for i, ph := range slice {
		binary.BigEndian.PutUint64(bz[i<<3:], uint64(ph))
	}
	return bz
}

func TestInt64SliceToBytesEquivalence(t *testing.T) {
	testCases := [][]int64{
		{},
		{0},
		{1, 2, 3},
		{-1, 123456789, -987654321},
		{9223372036854775807, -9223372036854775808}, // int64 最大/最小值
	}

	for _, tc := range testCases {
		got1 := int64SliceToBytesV1(tc...)
		got2 := int64SliceToBytesV2(tc...)

		if !bytes.Equal(got1, got2) {
			t.Errorf("Mismatch for input %v:\nV1=%v\nV2=%v", tc, got1, got2)
		}
	}
}

and this test pass.

[cuiweixie]

@aljo242 can you help with the gosec check failed. I do not understand the failed log.

[aljo242]

Can you unit test this and add a benchmark function for this?

[cuiweixie]

Can you unit test this and add a benchmark function for this?

done @aljo242

[aljo242]

@technicallyty for the final approval here

[cuiweixie]

@aljo242 Done

[cuiweixie]

gentle ping!

[technicallyty]

lgtm, thanks!

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 52.88%. Comparing base (abc3054) to head (8f76647).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #25360   +/-   ##
=======================================
  Coverage   52.87%   52.88%           
=======================================
  Files         797      797           
  Lines       64903    64903           
=======================================
+ Hits        34318    34321    +3     
+ Misses      30585    30582    -3     

see 2 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.