[7.x] Include min/max/average file size in Searchable Snapshots Stats…

… API (#70327)

This commit adds the minimum, maximum and average length
of files in the Searchable Snapshots Stats API.

Backport of #70294 for 7.x

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/searchablesnapshots/SearchableSnapshotShardStats.java

@@ -11,6 +11,7 @@
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.io.stream.Writeable;
+import org.elasticsearch.common.unit.ByteSizeValue;
 import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.common.xcontent.ToXContentObject;
 import org.elasticsearch.common.xcontent.XContentBuilder;
@@ -125,7 +126,9 @@ public static class CacheIndexInputStats implements Writeable, ToXContentObject
 
         private final String fileExt;
         private final long numFiles;
-        private final long totalSize;
+        private final ByteSizeValue totalSize;
+        private final ByteSizeValue minSize;
+        private final ByteSizeValue maxSize;
 
         private final long openCount;
         private final long closeCount;
@@ -144,7 +147,8 @@ public static class CacheIndexInputStats implements Writeable, ToXContentObject
         private final Counter blobStoreBytesRequested;
         private final long currentIndexCacheFills;
 
-        public CacheIndexInputStats(String fileExt, long numFiles, long totalSize, long openCount, long closeCount,
+        public CacheIndexInputStats(String fileExt, long numFiles, ByteSizeValue totalSize, ByteSizeValue minSize, ByteSizeValue maxSize,
+                                    long openCount, long closeCount,
                                     Counter forwardSmallSeeks, Counter backwardSmallSeeks,
                                     Counter forwardLargeSeeks, Counter backwardLargeSeeks,
                                     Counter contiguousReads, Counter nonContiguousReads,
@@ -154,6 +158,8 @@ public CacheIndexInputStats(String fileExt, long numFiles, long totalSize, long
             this.fileExt = fileExt;
             this.numFiles = numFiles;
             this.totalSize = totalSize;
+            this.minSize = minSize;
+            this.maxSize = maxSize;
             this.openCount = openCount;
             this.closeCount = closeCount;
             this.forwardSmallSeeks = forwardSmallSeeks;
@@ -180,7 +186,15 @@ public CacheIndexInputStats(String fileExt, long numFiles, long totalSize, long
             }
             this.fileExt = in.readString();
             this.numFiles = in.readVLong();
-            this.totalSize = in.readVLong();
+            if (in.getVersion().before(Version.V_7_13_0)) {
+                this.totalSize = new ByteSizeValue(in.readVLong());
+                this.minSize = ByteSizeValue.ZERO;
+                this.maxSize = ByteSizeValue.ZERO;
+            } else {
+                this.totalSize = new ByteSizeValue(in);
+                this.minSize = new ByteSizeValue(in);
+                this.maxSize = new ByteSizeValue(in);
+            }
             this.openCount = in.readVLong();
             this.closeCount = in.readVLong();
             this.forwardSmallSeeks = new Counter(in);
@@ -216,7 +230,9 @@ public static CacheIndexInputStats combine(CacheIndexInputStats cis1, CacheIndex
             return new CacheIndexInputStats(
                 cis1.fileExt,
                 cis1.numFiles + cis2.numFiles,
-                cis1.totalSize + cis2.totalSize,
+                new ByteSizeValue(Math.addExact(cis1.totalSize.getBytes(), cis2.totalSize.getBytes())),
+                new ByteSizeValue(Math.min(cis1.minSize.getBytes(), cis2.minSize.getBytes())),
+                new ByteSizeValue(Math.max(cis1.maxSize.getBytes(), cis2.maxSize.getBytes())),
                 cis1.openCount + cis2.openCount,
                 cis1.closeCount + cis2.closeCount,
                 cis1.forwardSmallSeeks.add(cis2.forwardSmallSeeks),
@@ -245,7 +261,13 @@ public void writeTo(StreamOutput out) throws IOException {
             }
             out.writeString(fileExt);
             out.writeVLong(numFiles);
-            out.writeVLong(totalSize);
+            if (out.getVersion().before(Version.V_7_13_0)) {
+                out.writeVLong(totalSize.getBytes());
+            } else {
+                totalSize.writeTo(out);
+                minSize.writeTo(out);
+                maxSize.writeTo(out);
+            }
             out.writeVLong(openCount);
             out.writeVLong(closeCount);
 
@@ -276,10 +298,23 @@ public long getNumFiles() {
             return numFiles;
         }
 
-        public long getTotalSize() {
+        public ByteSizeValue getTotalSize() {
             return totalSize;
         }
 
+        public ByteSizeValue getMinSize() {
+            return minSize;
+        }
+
+        public ByteSizeValue getMaxSize() {
+            return maxSize;
+        }
+
+        public ByteSizeValue getAverageSize() {
+            final double average = (double) totalSize.getBytes()/ (double) numFiles;
+            return new ByteSizeValue(Math.round(average));
+        }
+
         public long getOpenCount() {
             return openCount;
         }
@@ -346,9 +381,16 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
             {
                 builder.field("file_ext", getFileExt());
                 builder.field("num_files", getNumFiles());
-                builder.field("total_size", getTotalSize());
                 builder.field("open_count", getOpenCount());
                 builder.field("close_count", getCloseCount());
+                {
+                    builder.startObject("size");
+                    builder.humanReadableField("total_in_bytes", "total", getTotalSize());
+                    builder.humanReadableField("min_in_bytes", "min", getMinSize());
+                    builder.humanReadableField("max_in_bytes", "max", getMaxSize());
+                    builder.humanReadableField("average_in_bytes", "average", getAverageSize());
+                    builder.endObject();
+                }
                 builder.field("contiguous_bytes_read", getContiguousReads(), params);
                 builder.field("non_contiguous_bytes_read", getNonContiguousReads(), params);
                 builder.field("cached_bytes_read", getCachedBytesRead(), params);
@@ -384,10 +426,12 @@ public boolean equals(Object other) {
             }
             CacheIndexInputStats stats = (CacheIndexInputStats) other;
             return numFiles == stats.numFiles
-                && totalSize == stats.totalSize
                 && openCount == stats.openCount
                 && closeCount == stats.closeCount
                 && Objects.equals(fileExt, stats.fileExt)
+                && Objects.equals(totalSize, stats.totalSize)
+                && Objects.equals(minSize, stats.minSize)
+                && Objects.equals(maxSize, stats.maxSize)
                 && Objects.equals(forwardSmallSeeks, stats.forwardSmallSeeks)
                 && Objects.equals(backwardSmallSeeks, stats.backwardSmallSeeks)
                 && Objects.equals(forwardLargeSeeks, stats.forwardLargeSeeks)
@@ -405,7 +449,9 @@ public boolean equals(Object other) {
 
         @Override
         public int hashCode() {
-            return Objects.hash(fileExt, numFiles, totalSize, openCount, closeCount,
+            return Objects.hash(fileExt, numFiles, totalSize,
+                minSize, maxSize,
+                openCount, closeCount,
                 forwardSmallSeeks, backwardSmallSeeks,
                 forwardLargeSeeks, backwardLargeSeeks,
                 contiguousReads, nonContiguousReads,

x-pack/plugin/core/src/test/java/org/elasticsearch/xpack/core/searchablesnapshots/SearchableSnapshotShardStatsTests.java

@@ -10,6 +10,7 @@
 import org.elasticsearch.cluster.routing.ShardRoutingState;
 import org.elasticsearch.cluster.routing.TestShardRouting;
 import org.elasticsearch.common.io.stream.Writeable;
+import org.elasticsearch.common.unit.ByteSizeValue;
 import org.elasticsearch.repositories.IndexId;
 import org.elasticsearch.snapshots.SnapshotId;
 import org.elasticsearch.test.AbstractWireSerializingTestCase;
@@ -42,7 +43,8 @@ protected SearchableSnapshotShardStats createTestInstance() {
     }
 
     private CacheIndexInputStats randomCacheIndexInputStats() {
-        return new CacheIndexInputStats(randomAlphaOfLength(10), randomNonNegativeLong(), randomNonNegativeLong(),
+        return new CacheIndexInputStats(randomAlphaOfLength(10), randomNonNegativeLong(), new ByteSizeValue(randomNonNegativeLong()),
+            new ByteSizeValue(randomNonNegativeLong()), new ByteSizeValue(randomNonNegativeLong()),
             randomNonNegativeLong(), randomNonNegativeLong(),
             randomCounter(), randomCounter(),
             randomCounter(), randomCounter(),

x-pack/plugin/searchable-snapshots/qa/rest/src/test/resources/rest-api-spec/test/stats.yml

@@ -66,8 +66,8 @@ teardown:
 ---
 "Tests searchable snapshots stats":
   - skip:
-      version: " - 7.7.99"
-      reason:  searchable snapshots introduced in 7.8.0
+      version: " - 7.12.99"
+      reason:  searchable snapshots response format changed in 7.13.0
 
   - do:
       catch: missing
@@ -139,10 +139,14 @@ teardown:
   - is_true: total
   - is_true: total.0.file_ext
   - gt:      { total.0.num_files: 0 }
-  - gt:      { total.0.total_size: 0 }
   - gt:      { total.0.open_count: 0 }
   - gt:      { total.0.close_count: 0 }
 
+  - gt:      { total.0.size.total_in_bytes: 0 }
+  - gt:      { total.0.size.min_in_bytes: 0 }
+  - gt:      { total.0.size.max_in_bytes: 0 }
+  - gt:      { total.0.size.average_in_bytes: 0 }
+
   - gte:     { total.0.contiguous_bytes_read.count: 0 }
   - gte:     { total.0.contiguous_bytes_read.sum: 0 }
   - gte:     { total.0.contiguous_bytes_read.min: 0 }
@@ -215,10 +219,14 @@ teardown:
 
   - is_true: indices.docs.total.0.file_ext
   - gt:      { indices.docs.total.0.num_files: 0 }
-  - gt:      { indices.docs.total.0.total_size: 0 }
   - gt:      { indices.docs.total.0.open_count: 0 }
   - gt:      { indices.docs.total.0.close_count: 0 }
 
+  - gt:      { indices.docs.total.0.size.total_in_bytes: 0 }
+  - gt:      { indices.docs.total.0.size.min_in_bytes: 0 }
+  - gt:      { indices.docs.total.0.size.max_in_bytes: 0 }
+  - gt:      { indices.docs.total.0.size.average_in_bytes: 0 }
+
   - gte:     { indices.docs.total.0.contiguous_bytes_read.count: 0 }
   - gte:     { indices.docs.total.0.contiguous_bytes_read.sum: 0 }
   - gte:     { indices.docs.total.0.contiguous_bytes_read.min: 0 }
@@ -295,10 +303,14 @@ teardown:
 
   - is_true: indices.docs.shards.0.0.files.0.file_ext
   - gt:      { indices.docs.shards.0.0.files.0.num_files: 0 }
-  - gt:      { indices.docs.shards.0.0.files.0.total_size: 0 }
   - gt:      { indices.docs.shards.0.0.files.0.open_count: 0 }
   - gt:      { indices.docs.shards.0.0.files.0.close_count: 0 }
 
+  - gt:      { indices.docs.shards.0.0.files.0.size.total_in_bytes: 0 }
+  - gt:      { indices.docs.shards.0.0.files.0.size.min_in_bytes: 0 }
+  - gt:      { indices.docs.shards.0.0.files.0.size.max_in_bytes: 0 }
+  - gt:      { indices.docs.shards.0.0.files.0.size.average_in_bytes: 0 }
+
   - gte:     { indices.docs.shards.0.0.files.0.contiguous_bytes_read.count: 0 }
   - gte:     { indices.docs.shards.0.0.files.0.contiguous_bytes_read.sum: 0 }
   - gte:     { indices.docs.shards.0.0.files.0.contiguous_bytes_read.min: 0 }
@@ -373,6 +385,10 @@ teardown:
 
   - is_true:   indices.docs.shards.0.0.files.0.cached_bytes_written.time
   - is_true:   indices.docs.shards.0.0.files.0.direct_bytes_read.time
+  - is_true:   indices.docs.shards.0.0.files.0.size.total
+  - is_true:   indices.docs.shards.0.0.files.0.size.min
+  - is_true:   indices.docs.shards.0.0.files.0.size.max
+  - is_true:   indices.docs.shards.0.0.files.0.size.average
 
   - do:
       searchable_snapshots.stats:

x-pack/plugin/searchable-snapshots/src/internalClusterTest/java/org/elasticsearch/xpack/searchablesnapshots/SearchableSnapshotsIntegTests.java

@@ -1446,7 +1446,7 @@ private void assertSearchableSnapshotStats(String indexName, boolean cacheEnable
         final long totalSize = statsResponse.getStats()
             .stream()
             .flatMap(s -> s.getStats().stream())
-            .mapToLong(SearchableSnapshotShardStats.CacheIndexInputStats::getTotalSize)
+            .mapToLong(stat -> stat.getTotalSize().getBytes())
             .sum();
         final Set<String> nodeIdsWithLargeEnoughCache = new HashSet<>();
         for (ObjectCursor<DiscoveryNode> nodeCursor : client().admin()
@@ -1484,7 +1484,22 @@ private void assertSearchableSnapshotStats(String indexName, boolean cacheEnable
                     );
                     assertThat(
                         "Unexpected file length for " + fileExt + " of shard " + shardRouting,
-                        indexInputStats.getTotalSize(),
+                        indexInputStats.getTotalSize().getBytes(),
+                        greaterThan(0L)
+                    );
+                    assertThat(
+                        "Unexpected min. file length for " + fileExt + " of shard " + shardRouting,
+                        indexInputStats.getMinSize().getBytes(),
+                        greaterThan(0L)
+                    );
+                    assertThat(
+                        "Unexpected max. file length for " + fileExt + " of shard " + shardRouting,
+                        indexInputStats.getMaxSize().getBytes(),
+                        greaterThan(0L)
+                    );
+                    assertThat(
+                        "Unexpected average file length for " + fileExt + " of shard " + shardRouting,
+                        indexInputStats.getAverageSize().getBytes(),
                         greaterThan(0L)
                     );
 

x-pack/plugin/searchable-snapshots/src/main/java/org/elasticsearch/index/store/IndexInputStats.java

@@ -25,8 +25,11 @@ public class IndexInputStats {
     /* A threshold beyond which an index input seeking is counted as "large" */
     static final ByteSizeValue SEEKING_THRESHOLD = new ByteSizeValue(8, ByteSizeUnit.MB);
 
-    private final int numFiles;
+    private final long numFiles;
     private final long totalSize;
+    private final long minSize;
+    private final long maxSize;
+
     private final long seekingThreshold;
     private final LongSupplier currentTimeNanos;
 
@@ -52,13 +55,22 @@ public class IndexInputStats {
     private final Counter blobStoreBytesRequested = new Counter();
     private final AtomicLong currentIndexCacheFills = new AtomicLong();
 
-    public IndexInputStats(int numFiles, long totalSize, LongSupplier currentTimeNanos) {
-        this(numFiles, totalSize, SEEKING_THRESHOLD.getBytes(), currentTimeNanos);
+    public IndexInputStats(long numFiles, long totalSize, long minSize, long maxSize, LongSupplier currentTimeNanos) {
+        this(numFiles, totalSize, minSize, maxSize, SEEKING_THRESHOLD.getBytes(), currentTimeNanos);
     }
 
-    public IndexInputStats(int numFiles, long totalSize, long seekingThreshold, LongSupplier currentTimeNanos) {
+    public IndexInputStats(
+        long numFiles,
+        long totalSize,
+        long minSize,
+        long maxSize,
+        long seekingThreshold,
+        LongSupplier currentTimeNanos
+    ) {
         this.numFiles = numFiles;
         this.totalSize = totalSize;
+        this.minSize = minSize;
+        this.maxSize = maxSize;
         this.seekingThreshold = seekingThreshold;
         this.currentTimeNanos = currentTimeNanos;
     }
@@ -137,14 +149,22 @@ public Releasable addIndexCacheFill() {
         };
     }
 
-    public int getNumFiles() {
+    public long getNumFiles() {
         return numFiles;
     }
 
     public long getTotalSize() {
         return totalSize;
     }
 
+    public long getMinSize() {
+        return minSize;
+    }
+
+    public long getMaxSize() {
+        return maxSize;
+    }
+
     public LongAdder getOpened() {
         return opened;
     }

x-pack/plugin/searchable-snapshots/src/main/java/org/elasticsearch/index/store/SearchableSnapshotDirectory.java

@@ -360,8 +360,8 @@ public void clearCache() {
         }
     }
 
-    protected IndexInputStats createIndexInputStats(final int numFiles, final long totalSize) {
-        return new IndexInputStats(numFiles, totalSize, statsCurrentTimeNanosSupplier);
+    protected IndexInputStats createIndexInputStats(long numFiles, long totalSize, long minSize, long maxSize) {
+        return new IndexInputStats(numFiles, totalSize, minSize, maxSize, statsCurrentTimeNanosSupplier);
     }
 
     public CacheKey createCacheKey(String fileName) {
@@ -395,13 +395,13 @@ public IndexInput openInput(final String name, final IOContext context) throws I
 
         final String ext = getNonNullFileExt(name);
         final IndexInputStats inputStats = stats.computeIfAbsent(ext, n -> {
-            // get all fileInfo with same extension
-            final Tuple<Integer, Long> fileExtCompoundStats = files().stream()
-                .filter(fi -> ext.equals(getNonNullFileExt(fi.physicalName())))
-                .map(fi -> Tuple.tuple(1, fi.length()))
-                .reduce((t1, t2) -> Tuple.tuple(t1.v1() + t2.v1(), t1.v2() + t2.v2()))
-                .get();
-            return createIndexInputStats(fileExtCompoundStats.v1(), fileExtCompoundStats.v2());
+            final IndexInputStats.Counter counter = new IndexInputStats.Counter();
+            for (BlobStoreIndexShardSnapshot.FileInfo file : files()) {
+                if (ext.equals(getNonNullFileExt(file.physicalName()))) {
+                    counter.add(file.length());
+                }
+            }
+            return createIndexInputStats(counter.count(), counter.total(), counter.min(), counter.max());
         });
         if (useCache && isExcludedFromCache(name) == false) {
             if (partial) {

x-pack/plugin/searchable-snapshots/src/main/java/org/elasticsearch/xpack/searchablesnapshots/action/SearchableSnapshotsStatsResponse.java

@@ -65,6 +65,7 @@ private static List<CacheIndexInputStats> computeCompound(Stream<CacheIndexInput
             .stream()
             .filter(Optional::isPresent)
             .map(Optional::get)
+            .sorted(Comparator.comparing(CacheIndexInputStats::getFileExt))
             .collect(toList());
     }