diff --git a/milli/src/update/new/extract/faceted/mod.rs b/milli/src/update/new/extract/faceted/mod.rs
index bd58c21b4..62aa7adb2 100644
--- a/milli/src/update/new/extract/faceted/mod.rs
+++ b/milli/src/update/new/extract/faceted/mod.rs
@@ -17,6 +17,7 @@ mod extract_facets;
 mod facet_document;
 
 pub trait FacetedExtractor {
+    #[tracing::instrument(level = "trace", skip_all, target = "indexing::extract::faceted")]
     fn run_extraction(
         index: &Index,
         fields_ids_map: &GlobalFieldsIdsMap,
diff --git a/milli/src/update/new/indexer/mod.rs b/milli/src/update/new/indexer/mod.rs
index 0865374c8..5e3104de8 100644
--- a/milli/src/update/new/indexer/mod.rs
+++ b/milli/src/update/new/indexer/mod.rs
@@ -63,8 +63,11 @@ where
 
     thread::scope(|s| {
         // TODO manage the errors correctly
+        let current_span = tracing::Span::current();
         let handle = Builder::new().name(S("indexer-extractors")).spawn_scoped(s, move || {
             pool.in_place_scope(|_s| {
+                    let span = tracing::trace_span!(target: "indexing::documents", parent: &current_span, "extract");
+                    let _entered = span.enter();
                     let document_changes = document_changes.into_par_iter();
 
                     // document but we need to create a function that collects and compresses documents.
@@ -95,56 +98,85 @@ where
                         max_memory: Some(max_memory),
                         ..GrenadParameters::default()
                     };
-                    extract_and_send_docids::<WordDocidsExtractor, WordDocids>(
-                        index,
-                        &global_fields_ids_map,
-                        grenad_parameters,
-                        document_changes.clone(),
-                        &extractor_sender,
-                    )?;
+                    {
+                        let span = tracing::trace_span!(target: "indexing::documents::extract", "word_docids");
+                        let _entered = span.enter();
+                        extract_and_send_docids::<WordDocidsExtractor, WordDocids>(
+                            index,
+                            &global_fields_ids_map,
+                            grenad_parameters,
+                            document_changes.clone(),
+                            &extractor_sender,
+                        )?;
+                    }
 
-                    extract_and_send_docids::<WordFidDocidsExtractor, WordFidDocids>(
-                        index,
-                        &global_fields_ids_map,
-                        grenad_parameters,
-                        document_changes.clone(),
-                        &extractor_sender,
-                    )?;
+                    {
+                        let span = tracing::trace_span!(target: "indexing::documents::extract", "word_fid_docids");
+                        let _entered = span.enter();
+                        extract_and_send_docids::<WordFidDocidsExtractor, WordFidDocids>(
+                            index,
+                            &global_fields_ids_map,
+                            grenad_parameters,
+                            document_changes.clone(),
+                            &extractor_sender,
+                        )?;
+                    }
+                    
+                    {
+                        let span = tracing::trace_span!(target: "indexing::documents::extract", "exact_word_docids");
+                        let _entered = span.enter();
+                        extract_and_send_docids::<ExactWordDocidsExtractor, ExactWordDocids>(
+                            index,
+                            &global_fields_ids_map,
+                            grenad_parameters,
+                            document_changes.clone(),
+                            &extractor_sender,
+                        )?;
+                    }
 
-                    extract_and_send_docids::<ExactWordDocidsExtractor, ExactWordDocids>(
-                        index,
-                        &global_fields_ids_map,
-                        grenad_parameters,
-                        document_changes.clone(),
-                        &extractor_sender,
-                    )?;
+                    {
+                        let span = tracing::trace_span!(target: "indexing::documents::extract", "word_position_docids");
+                        let _entered = span.enter();
+                        extract_and_send_docids::<WordPositionDocidsExtractor, WordPositionDocids>(
+                            index,
+                            &global_fields_ids_map,
+                            grenad_parameters,
+                            document_changes.clone(),
+                            &extractor_sender,
+                        )?;
+                    }
 
-                    extract_and_send_docids::<WordPositionDocidsExtractor, WordPositionDocids>(
-                        index,
-                        &global_fields_ids_map,
-                        grenad_parameters,
-                        document_changes.clone(),
-                        &extractor_sender,
-                    )?;
+                    {
+                        let span = tracing::trace_span!(target: "indexing::documents::extract", "fid_word_count_docids");
+                        let _entered = span.enter();
+                        extract_and_send_docids::<FidWordCountDocidsExtractor, FidWordCountDocids>(
+                            index,
+                            &global_fields_ids_map,
+                            GrenadParameters::default(),
+                            document_changes.clone(),
+                            &extractor_sender,
+                        )?;
+                    }
 
-                    extract_and_send_docids::<FidWordCountDocidsExtractor, FidWordCountDocids>(
-                        index,
-                        &global_fields_ids_map,
-                        GrenadParameters::default(),
-                        document_changes.clone(),
-                        &extractor_sender,
-                    )?;
+                    {
+                        let span = tracing::trace_span!(target: "indexing::documents::extract", "word_pair_proximity_docids");
+                        let _entered = span.enter();
+                        extract_and_send_docids::<
+                            WordPairProximityDocidsExtractor,
+                            WordPairProximityDocids,
+                        >(
+                            index,
+                            &global_fields_ids_map,
+                            grenad_parameters,
+                            document_changes.clone(),
+                            &extractor_sender,
+                        )?;
+                    }
 
-                    extract_and_send_docids::<
-                        WordPairProximityDocidsExtractor,
-                        WordPairProximityDocids,
-                    >(
-                        index,
-                        &global_fields_ids_map,
-                        grenad_parameters,
-                        document_changes.clone(),
-                        &extractor_sender,
-                    )?;
+                    {
+                        let span = tracing::trace_span!(target: "indexing::documents::extract", "FINISH");
+                        let _entered = span.enter();
+                    }
 
                     // TODO THIS IS TOO MUCH
                     // Extract fieldid docid facet number
@@ -166,7 +198,11 @@ where
         })?;
 
         // TODO manage the errors correctly
+        let current_span = tracing::Span::current();
         let handle2 = Builder::new().name(S("indexer-merger")).spawn_scoped(s, move || {
+            let span =
+                tracing::trace_span!(target: "indexing::documents", parent: &current_span, "merge");
+            let _entered = span.enter();
             let rtxn = index.read_txn().unwrap();
             merge_grenad_entries(merger_receiver, merger_sender, &rtxn, index)
         })?;
diff --git a/milli/src/update/new/merger.rs b/milli/src/update/new/merger.rs
index 19f56a301..b38dc0865 100644
--- a/milli/src/update/new/merger.rs
+++ b/milli/src/update/new/merger.rs
@@ -16,6 +16,7 @@ use crate::update::MergeDeladdCboRoaringBitmaps;
 use crate::{CboRoaringBitmapCodec, Index, Result};
 
 /// TODO We must return some infos/stats
+#[tracing::instrument(level = "trace", skip_all, target = "indexing::documents", name = "merge")]
 pub fn merge_grenad_entries(
     receiver: MergerReceiver,
     sender: MergerSender,
@@ -28,6 +29,9 @@ pub fn merge_grenad_entries(
     for merger_operation in receiver {
         match merger_operation {
             MergerOperation::ExactWordDocidsMerger(merger) => {
+                let span =
+                    tracing::trace_span!(target: "indexing::documents::merge", "exact_word_docids");
+                let _entered = span.enter();
                 merge_and_send_docids(
                     merger,
                     /// TODO do a MergerOperation::database(&Index) -> Database<Bytes, Bytes>.
@@ -40,6 +44,8 @@ pub fn merge_grenad_entries(
                 )?;
             }
             MergerOperation::FidWordCountDocidsMerger(merger) => {
+                let span = tracing::trace_span!(target: "indexing::documents::merge", "fid_word_count_docids");
+                let _entered = span.enter();
                 merge_and_send_docids(
                     merger,
                     index.field_id_word_count_docids.remap_types(),
@@ -51,6 +57,9 @@ pub fn merge_grenad_entries(
                 )?;
             }
             MergerOperation::WordDocidsMerger(merger) => {
+                let span =
+                    tracing::trace_span!(target: "indexing::documents::merge", "word_docids");
+                let _entered = span.enter();
                 let mut add_words_fst = SetBuilder::new(tempfile()?)?;
                 let mut del_words_fst = SetBuilder::new(tempfile()?)?;
 
@@ -70,6 +79,9 @@ pub fn merge_grenad_entries(
                 sender.main().write_words_fst(mmap).unwrap();
             }
             MergerOperation::WordFidDocidsMerger(merger) => {
+                let span =
+                    tracing::trace_span!(target: "indexing::documents::merge", "word_fid_docids");
+                let _entered = span.enter();
                 merge_and_send_docids(
                     merger,
                     index.word_fid_docids.remap_types(),
@@ -81,6 +93,8 @@ pub fn merge_grenad_entries(
                 )?;
             }
             MergerOperation::WordPairProximityDocidsMerger(merger) => {
+                let span = tracing::trace_span!(target: "indexing::documents::merge", "word_pair_proximity_docids");
+                let _entered = span.enter();
                 merge_and_send_docids(
                     merger,
                     index.word_pair_proximity_docids.remap_types(),
@@ -92,6 +106,8 @@ pub fn merge_grenad_entries(
                 )?;
             }
             MergerOperation::WordPositionDocidsMerger(merger) => {
+                let span = tracing::trace_span!(target: "indexing::documents::merge", "word_position_docids");
+                let _entered = span.enter();
                 merge_and_send_docids(
                     merger,
                     index.word_position_docids.remap_types(),
@@ -103,10 +119,16 @@ pub fn merge_grenad_entries(
                 )?;
             }
             MergerOperation::InsertDocument { docid, document } => {
+                let span =
+                    tracing::trace_span!(target: "indexing::documents::merge", "insert_document");
+                let _entered = span.enter();
                 documents_ids.insert(docid);
                 sender.documents().uncompressed(docid, &document).unwrap();
             }
             MergerOperation::DeleteDocument { docid } => {
+                let span =
+                    tracing::trace_span!(target: "indexing::documents::merge", "delete_document");
+                let _entered = span.enter();
                 if !documents_ids.remove(docid) {
                     unreachable!("Tried deleting a document that we do not know about");
                 }
@@ -115,10 +137,15 @@ pub fn merge_grenad_entries(
         }
     }
 
-    // Send the documents ids unionized with the current one
-    /// TODO return the slice of bytes directly
-    serialize_bitmap_into_vec(&documents_ids, &mut buffer);
-    sender.send_documents_ids(&buffer).unwrap();
+    {
+        let span = tracing::trace_span!(target: "indexing::documents::merge", "documents_ids");
+        let _entered = span.enter();
+
+        // Send the documents ids unionized with the current one
+        /// TODO return the slice of bytes directly
+        serialize_bitmap_into_vec(&documents_ids, &mut buffer);
+        sender.send_documents_ids(&buffer).unwrap();
+    }
 
     // ...
 
@@ -149,6 +176,7 @@ fn compute_new_words_fst(
     Ok(words_fst_mmap)
 }
 
+#[tracing::instrument(level = "trace", skip_all, target = "indexing::merge")]
 fn merge_and_send_docids<D: DatabaseType>(
     merger: Merger<File, MergeDeladdCboRoaringBitmaps>,
     database: Database<Bytes, Bytes>,
diff --git a/workloads/movies.json b/workloads/movies.json
index 445ff3aca..9ad3fb7eb 100644
--- a/workloads/movies.json
+++ b/workloads/movies.json
@@ -1,6 +1,6 @@
 {
   "name": "movies.json",
-  "run_count": 10,
+  "run_count": 1,
   "extra_cli_args": [],
   "assets": {
     "movies.json": {