From 8bc110458568bb0e62dcb37e3a07d3c38ac03032 Mon Sep 17 00:00:00 2001
From: Matt Jaffee <matthew.jaffee@gmail.com>
Date: Tue, 20 Nov 2018 08:56:12 -0600
Subject: [PATCH] fix fragment checksums race condition

---
 fragment.go               |  6 +++---
 fragment_internal_test.go | 17 +++++++++++++++++
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/fragment.go b/fragment.go
index a4e4fd72d..bab1f3ec0 100644
--- a/fragment.go
+++ b/fragment.go
@@ -1492,9 +1492,6 @@ func (f *fragment) bulkImportStandard(rowIDs, columnIDs []uint64, options *Impor
 			lastRowID = rowID
 			rowSet[rowID] = struct{}{}
 		}
-
-		// Invalidate block checksum.
-		delete(f.checksums, int(rowID/HashBlockSize))
 	}
 
 	f.mu.Lock()
@@ -1518,6 +1515,9 @@ func (f *fragment) bulkImportStandard(rowIDs, columnIDs []uint64, options *Impor
 
 	// Update cache counts for all affected rows.
 	for rowID := range rowSet {
+		// Invalidate block checksum.
+		delete(f.checksums, int(rowID/HashBlockSize))
+
 		n := results.CountRange(rowID*ShardWidth, (rowID+1)*ShardWidth)
 		f.cache.BulkAdd(rowID, n)
 	}
diff --git a/fragment_internal_test.go b/fragment_internal_test.go
index 4e3007957..b36bf3380 100644
--- a/fragment_internal_test.go
+++ b/fragment_internal_test.go
@@ -25,6 +25,8 @@ import (
 	"testing"
 	"testing/quick"
 
+	"golang.org/x/sync/errgroup"
+
 	"github.com/davecgh/go-spew/spew"
 	"github.com/pilosa/pilosa/pql"
 	"github.com/pilosa/pilosa/roaring"
@@ -1399,6 +1401,21 @@ func TestFragment_ImportSet(t *testing.T) {
 	}
 }
 
+func TestFragment_ConcurrentImport(t *testing.T) {
+	t.Run("bulkImportStandard", func(t *testing.T) {
+		f := mustOpenFragment("i", "f", viewStandard, 0, "")
+		defer f.Close()
+
+		eg := errgroup.Group{}
+		eg.Go(func() error { return f.bulkImportStandard([]uint64{1, 2}, []uint64{1, 2}, &ImportOptions{}) })
+		eg.Go(func() error { return f.bulkImportStandard([]uint64{3, 4}, []uint64{3, 4}, &ImportOptions{}) })
+		err := eg.Wait()
+		if err != nil {
+			t.Fatalf("importing data to fragment: %v", err)
+		}
+	})
+}
+
 // Ensure a fragment can import mutually exclusive values.
 func TestFragment_ImportMutex(t *testing.T) {
 	tests := []struct {