[improve](tablet_lock) do not hold tablet lock when clearing cache

We found that clearing cache sometimes consums a lot time, so do not
hold lock when clearing cache and trace time-consuming cache clearing.

be/src/olap/rowset/rowset.cpp

@@ -23,6 +23,7 @@
 #include "olap/segment_loader.h"
 #include "olap/tablet_schema.h"
 #include "util/time.h"
+#include "util/trace.h"
 
 namespace doris {
 
@@ -118,8 +119,14 @@ std::string Rowset::get_rowset_info_str() {
 }
 
 void Rowset::clear_cache() {
-    SegmentLoader::instance()->erase_segments(rowset_id(), num_segments());
-    clear_inverted_index_cache();
+    {
+        SCOPED_SIMPLE_TRACE_IF_TIMEOUT(std::chrono::seconds(1));
+        SegmentLoader::instance()->erase_segments(rowset_id(), num_segments());
+    }
+    {
+        SCOPED_SIMPLE_TRACE_IF_TIMEOUT(std::chrono::seconds(1));
+        clear_inverted_index_cache();
+    }
 }
 
 Result<std::string> Rowset::segment_path(int64_t seg_id) {

be/src/olap/tablet.cpp

@@ -2649,14 +2649,21 @@ Status Tablet::ingest_binlog_metas(RowsetBinlogMetasPB* metas_pb) {
 }
 
 void Tablet::clear_cache() {
-    std::shared_lock rlock(get_header_lock());
-    static auto recycle_segment_cache = [](const auto& rowset_map) {
-        for (auto& [_, rowset] : rowset_map) {
-            rowset->clear_cache();
+    std::list<RowsetSharedPtr> rowsets;
+    {
+        std::shared_lock rlock(get_header_lock());
+        SCOPED_SIMPLE_TRACE_IF_TIMEOUT(TRACE_TABLET_LOCK_THRESHOLD);
+
+        for (auto& [_, rowset] : rowset_map()) {
+            rowsets.push_back(rowset);
         }
-    };
-    recycle_segment_cache(rowset_map());
-    recycle_segment_cache(stale_rowset_map());
+        for (auto& [_, rowset] : stale_rowset_map()) {
+            rowsets.push_back(rowset);
+        }
+    }
+    for (auto& rowset : rowsets) {
+        rowset->clear_cache();
+    }
 }
 
 } // namespace doris