Merge pull request #52518 from CurtizJ/add-refcount-to-system-table

Added field `refcount` to `system.remote_data_paths` table

src/Disks/IDisk.h

@@ -303,10 +303,11 @@ public:
         std::string local_path;
         std::string common_prefix_for_objects;
         StoredObjects objects;
+        size_t refcount;
 
         LocalPathWithObjectStoragePaths(
-            const std::string & local_path_, const std::string & common_prefix_for_objects_, StoredObjects && objects_)
+            const std::string & local_path_, const std::string & common_prefix_for_objects_, StoredObjects && objects_, size_t refcount_)
-            : local_path(local_path_), common_prefix_for_objects(common_prefix_for_objects_), objects(std::move(objects_)) {}
+            : local_path(local_path_), common_prefix_for_objects(common_prefix_for_objects_), objects(std::move(objects_)), refcount(refcount_) {}
     };
 
     virtual void getRemotePathsRecursive(const String &, std::vector<LocalPathWithObjectStoragePaths> &)

src/Disks/ObjectStorages/DiskObjectStorage.cpp

@@ -82,7 +82,7 @@ void DiskObjectStorage::getRemotePathsRecursive(const String & local_path, std::
     {
         try
         {
-            paths_map.emplace_back(local_path, metadata_storage->getObjectStorageRootPath(), getStorageObjects(local_path));
+            paths_map.emplace_back(local_path, metadata_storage->getObjectStorageRootPath(), getStorageObjects(local_path), metadata_storage->getHardlinkCount(local_path));
         }
         catch (const Exception & e)
         {

src/Storages/System/StorageSystemRemoteDataPaths.cpp

@@ -25,6 +25,7 @@ StorageSystemRemoteDataPaths::StorageSystemRemoteDataPaths(const StorageID & tab
         {"local_path", std::make_shared<DataTypeString>()},
         {"remote_path", std::make_shared<DataTypeString>()},
         {"size", std::make_shared<DataTypeUInt64>()},
+        {"refcount", std::make_shared<DataTypeUInt64>()},
         {"common_prefix_for_blobs", std::make_shared<DataTypeString>()},
         {"cache_paths", std::make_shared<DataTypeArray>(std::make_shared<DataTypeString>())},
     }));
@@ -48,6 +49,7 @@ Pipe StorageSystemRemoteDataPaths::read(
     MutableColumnPtr col_local_path = ColumnString::create();
     MutableColumnPtr col_remote_path = ColumnString::create();
     MutableColumnPtr col_size = ColumnUInt64::create();
+    MutableColumnPtr col_refcount = ColumnUInt64::create();
     MutableColumnPtr col_namespace = ColumnString::create();
     MutableColumnPtr col_cache_paths = ColumnArray::create(ColumnString::create());
 
@@ -65,19 +67,22 @@ Pipe StorageSystemRemoteDataPaths::read(
             if (disk->supportsCache())
                 cache = FileCacheFactory::instance().getByName(disk->getCacheName()).cache;
 
-            for (const auto & [local_path, common_prefox_for_objects, storage_objects] : remote_paths_by_local_path)
+            for (const auto & [local_path, common_prefox_for_objects, storage_objects, refcount] : remote_paths_by_local_path)
             {
                 for (const auto & object : storage_objects)
                 {
                     col_disk_name->insert(disk_name);
                     col_base_path->insert(disk->getPath());
+
                     if (cache)
                         col_cache_base_path->insert(cache->getBasePath());
                     else
                         col_cache_base_path->insertDefault();
+
                     col_local_path->insert(local_path);
                     col_remote_path->insert(object.remote_path);
                     col_size->insert(object.bytes_size);
+                    col_refcount->insert(refcount);
                     col_namespace->insert(common_prefox_for_objects);
 
                     if (cache)
@@ -101,6 +106,7 @@ Pipe StorageSystemRemoteDataPaths::read(
     res_columns.emplace_back(std::move(col_local_path));
     res_columns.emplace_back(std::move(col_remote_path));
     res_columns.emplace_back(std::move(col_size));
+    res_columns.emplace_back(std::move(col_refcount));
     res_columns.emplace_back(std::move(col_namespace));
     res_columns.emplace_back(std::move(col_cache_paths));
 

tests/queries/0_stateless/02791_remote_paths_refcount.reference

@@ -0,0 +1,28 @@
+0_0_0_0	0
+0_0_0_0_1	1
+1_0_0_0	0
+1_0_0_0_1	1
+0_0_0_0_1	checksums.txt	0
+0_0_0_0_1	columns.txt	1
+0_0_0_0_1	count.txt	1
+0_0_0_0_1	default_compression_codec.txt	1
+0_0_0_0_1	id.bin	1
+0_0_0_0_1	id.cmrk2	1
+0_0_0_0_1	metadata_version.txt	1
+0_0_0_0_1	minmax_id.idx	1
+0_0_0_0_1	partition.dat	1
+0_0_0_0_1	primary.cidx	1
+0_0_0_0_1	v.bin	1
+0_0_0_0_1	v.cmrk2	1
+1_0_0_0_1	checksums.txt	0
+1_0_0_0_1	columns.txt	0
+1_0_0_0_1	count.txt	1
+1_0_0_0_1	default_compression_codec.txt	0
+1_0_0_0_1	id.bin	1
+1_0_0_0_1	id.cmrk2	1
+1_0_0_0_1	metadata_version.txt	0
+1_0_0_0_1	minmax_id.idx	1
+1_0_0_0_1	partition.dat	1
+1_0_0_0_1	primary.cidx	1
+1_0_0_0_1	v.bin	0
+1_0_0_0_1	v.cmrk2	0

tests/queries/0_stateless/02791_remote_paths_refcount.sql

@@ -0,0 +1,47 @@
+-- Tags: no-fasttest
+
+DROP TABLE IF EXISTS t_refcount SYNC;
+
+-- Names of parts (on which this test depends)
+-- can differ in case of fault injection.
+SET insert_keeper_fault_injection_probability = 0.0;
+
+CREATE TABLE t_refcount (id UInt64, v UInt64)
+ENGINE = ReplicatedMergeTree('/clickhouse/test/{database}/t_refcount', '1')
+ORDER BY id PARTITION BY id % 2
+SETTINGS
+    storage_policy = 's3_cache',
+    allow_remote_fs_zero_copy_replication = 1,
+    min_bytes_for_wide_part = 0,
+    compress_marks = 1,
+    compress_primary_key = 1,
+    ratio_of_defaults_for_sparse_serialization = 1.0;
+
+INSERT INTO t_refcount VALUES (1, 10), (2, 20);
+
+SET mutations_sync = 2;
+ALTER TABLE t_refcount UPDATE v = v * 10 WHERE id % 2 = 1;
+
+SELECT name, active FROM system.parts WHERE database = currentDatabase() AND table = 't_refcount' ORDER BY name;
+
+WITH splitByChar('/', full_path) AS path_parts
+SELECT path_parts[-2] AS part_name, path_parts[-1] AS file_name, refcount
+FROM
+(
+    SELECT
+        path || local_path AS full_path,
+        substring(full_path, 1, length(full_path) - position(reverse(full_path), '/') + 1) AS part_path,
+        refcount
+    FROM system.remote_data_paths
+    WHERE disk_name = 's3_cache'
+) AS paths
+INNER JOIN
+(
+    SELECT path
+    FROM system.parts
+    WHERE database = currentDatabase() AND table = 't_refcount' AND active
+) AS parts
+ON paths.part_path = parts.path
+ORDER BY part_name, file_name;
+
+DROP TABLE IF EXISTS t_refcount SYNC;