feat: add more spans to mito engine (#4643)

feat: add more span on mito engine

src/mito2/src/read/scan_region.rs

@@ -20,7 +20,7 @@ use std::time::{Duration, Instant};
 
 use common_error::ext::BoxedError;
 use common_recordbatch::SendableRecordBatchStream;
-use common_telemetry::{debug, error, warn};
+use common_telemetry::{debug, error, tracing, warn};
 use common_time::range::TimestampRange;
 use common_time::Timestamp;
 use datafusion::physical_plan::DisplayFormatType;
@@ -62,6 +62,7 @@ pub(crate) enum Scanner {
 
 impl Scanner {
     /// Returns a [SendableRecordBatchStream] to retrieve scan results from all partitions.
+    #[tracing::instrument(level = tracing::Level::DEBUG, skip_all)]
     pub(crate) async fn scan(&self) -> Result<SendableRecordBatchStream, BoxedError> {
         match self {
             Scanner::Seq(seq_scan) => seq_scan.build_stream(),
@@ -70,6 +71,7 @@ impl Scanner {
     }
 
     /// Returns a [RegionScanner] to scan the region.
+    #[tracing::instrument(level = tracing::Level::DEBUG, skip_all)]
     pub(crate) async fn region_scanner(self) -> Result<RegionScannerRef> {
         match self {
             Scanner::Seq(seq_scan) => Ok(Box::new(seq_scan)),

src/mito2/src/read/seq_scan.rs

@@ -23,7 +23,7 @@ use common_error::ext::BoxedError;
 use common_recordbatch::error::ExternalSnafu;
 use common_recordbatch::util::ChainedRecordBatchStream;
 use common_recordbatch::{RecordBatchStreamWrapper, SendableRecordBatchStream};
-use common_telemetry::debug;
+use common_telemetry::{debug, tracing};
 use datafusion::physical_plan::{DisplayAs, DisplayFormatType};
 use datatypes::schema::SchemaRef;
 use smallvec::smallvec;
@@ -248,6 +248,7 @@ impl SeqScan {
         maybe_reader
     }
 
+    #[tracing::instrument(level = tracing::Level::DEBUG, skip_all)]
     async fn build_reader_from_sources(
         stream_ctx: &StreamContext,
         mut sources: Vec<Source>,