sstable: capture elided prefix in a prop

cockroachdb · Jan 23, 2024 · 3b862af · 3b862af
1 parent b5139bb
commit 3b862af
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Showing 6 changed files with 17 additions and 9 deletions.
diff --git a/sstable/properties.go b/sstable/properties.go
@@ -134,6 +134,9 @@ type Properties struct {
 	CompressionOptions string `prop:"rocksdb.compression_options"`
 	// The total size of all data blocks.
 	DataSize uint64 `prop:"rocksdb.data.size"`
+	// ElidedPrefix is the byte prefix, if any, that was elided from every key and
+	// key span during the construction of the sstable.
+	ElidedPrefix string `prop:"pebble.elided_prefix"`
 	// The external sstable version format. Version 2 is the one RocksDB has been
 	// using since 5.13. RocksDB only uses the global sequence number for an
 	// sstable if this property has been set.
@@ -428,7 +431,9 @@ func (p *Properties) save(tblFormat TableFormat, w *rawBlockWriter) {
 		p.saveUvarint(m, unsafe.Offsetof(p.ValueBlocksSize), p.ValueBlocksSize)
 	}
 	p.saveBool(m, unsafe.Offsetof(p.WholeKeyFiltering), p.WholeKeyFiltering)
-
+	if p.ElidedPrefix != "" {
+		p.saveString(m, unsafe.Offsetof(p.ElidedPrefix), p.ElidedPrefix)
+	}
 	if tblFormat < TableFormatPebblev1 {
 		m["rocksdb.column.family.id"] = binary.AppendUvarint([]byte(nil), math.MaxInt32)
 		m["rocksdb.fixed.key.length"] = []byte{0x00}

diff --git a/sstable/testdata/writer b/sstable/testdata/writer
@@ -369,7 +369,7 @@ layout
        821  footer (53)
        874  EOF
 
-build elide-prefix=foo_
+build elide-prefix=foo_ props=(elided)
 foo_a.SET.1:a
 foo_b.DEL.2:
 foo_c.MERGE.3:c
@@ -386,3 +386,5 @@ point:    [a#1,1-h#7,2]
 rangedel: [d#4,15-j#72057594037927935,15]
 rangekey: [j#9,19-m#72057594037927935,21]
 seqnums:  [1-11]
+props "elided":
+  pebble.elided_prefix: foo_
diff --git a/sstable/writer.go b/sstable/writer.go
@@ -2303,6 +2303,7 @@ func NewWriter(writable objstorage.Writable, o WriterOptions, extraOpts ...Write
 	w.props.MergerName = o.MergerName
 	w.props.PropertyCollectorNames = "[]"
 	w.props.ExternalFormatVersion = rocksDBExternalFormatVersion
+	w.props.ElidedPrefix = string(o.ElidePrefix)
 
 	if len(o.BlockPropertyCollectors) > 0 || w.tableFormat >= TableFormatPebblev4 {
 		var buf bytes.Buffer

diff --git a/testdata/event_listener b/testdata/event_listener
@@ -222,7 +222,7 @@ Zombie tables: 0 (0B)
 Backing tables: 0 (0B)
 Virtual tables: 0 (0B)
 Block cache: 6 entries (1.1KB)  hit rate: 11.1%
-Table cache: 1 entries (808B)  hit rate: 40.0%
+Table cache: 1 entries (824B)  hit rate: 40.0%
 Secondary cache: 0 entries (0B)  hit rate: 0.0%
 Snapshots: 0  earliest seq num: 0
 Table iters: 0
@@ -321,7 +321,7 @@ Zombie tables: 0 (0B)
 Backing tables: 0 (0B)
 Virtual tables: 0 (0B)
 Block cache: 12 entries (2.3KB)  hit rate: 14.3%
-Table cache: 1 entries (808B)  hit rate: 50.0%
+Table cache: 1 entries (824B)  hit rate: 50.0%
 Secondary cache: 0 entries (0B)  hit rate: 0.0%
 Snapshots: 0  earliest seq num: 0
 Table iters: 0

diff --git a/testdata/ingest b/testdata/ingest
@@ -52,7 +52,7 @@ Zombie tables: 0 (0B)
 Backing tables: 0 (0B)
 Virtual tables: 0 (0B)
 Block cache: 6 entries (1.2KB)  hit rate: 35.7%
-Table cache: 1 entries (808B)  hit rate: 50.0%
+Table cache: 1 entries (824B)  hit rate: 50.0%
 Secondary cache: 0 entries (0B)  hit rate: 0.0%
 Snapshots: 0  earliest seq num: 0
 Table iters: 0

diff --git a/testdata/metrics b/testdata/metrics
@@ -68,7 +68,7 @@ Zombie tables: 0 (0B)
 Backing tables: 0 (0B)
 Virtual tables: 0 (0B)
 Block cache: 3 entries (556B)  hit rate: 0.0%
-Table cache: 1 entries (808B)  hit rate: 0.0%
+Table cache: 1 entries (824B)  hit rate: 0.0%
 Secondary cache: 0 entries (0B)  hit rate: 0.0%
 Snapshots: 0  earliest seq num: 0
 Table iters: 1
@@ -201,7 +201,7 @@ Zombie tables: 1 (661B)
 Backing tables: 0 (0B)
 Virtual tables: 0 (0B)
 Block cache: 3 entries (556B)  hit rate: 42.9%
-Table cache: 1 entries (808B)  hit rate: 66.7%
+Table cache: 1 entries (824B)  hit rate: 66.7%
 Secondary cache: 0 entries (0B)  hit rate: 0.0%
 Snapshots: 0  earliest seq num: 0
 Table iters: 1
@@ -467,7 +467,7 @@ Zombie tables: 0 (0B)
 Backing tables: 0 (0B)
 Virtual tables: 0 (0B)
 Block cache: 12 entries (2.4KB)  hit rate: 24.5%
-Table cache: 1 entries (808B)  hit rate: 60.0%
+Table cache: 1 entries (824B)  hit rate: 60.0%
 Secondary cache: 0 entries (0B)  hit rate: 0.0%
 Snapshots: 0  earliest seq num: 0
 Table iters: 0
@@ -528,7 +528,7 @@ Zombie tables: 0 (0B)
 Backing tables: 0 (0B)
 Virtual tables: 0 (0B)
 Block cache: 12 entries (2.4KB)  hit rate: 24.5%
-Table cache: 1 entries (808B)  hit rate: 60.0%
+Table cache: 1 entries (824B)  hit rate: 60.0%
 Secondary cache: 0 entries (0B)  hit rate: 0.0%
 Snapshots: 0  earliest seq num: 0
 Table iters: 0