diff --git a/README.md b/README.md
index 93b380ad..f178a5ef 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 <div align="center">
 
-  ![minitrace: Extremely fast tracing library for Rust](etc/img/head-img-640.svg)
+  ![minitrace: Extremely fast tracing library for Rust](https://raw.githubusercontent.com/tikv/minitrace-rust/master/etc/img/head-img-640.svg)
 
   [![Crates.io](https://img.shields.io/crates/v/minitrace.svg?style=flat-square&logo=rust)](https://crates.io/crates/minitrace)
   [![Documentation](https://img.shields.io/docsrs/minitrace?style=flat-square&logo=rust)](https://docs.rs/minitrace/)
@@ -13,7 +13,7 @@
 
 minitrace is a tracing library [10~100x faster](#benchmarks) than others:
 
-![benchmark](etc/img/head-benchmark.svg)
+![benchmark](https://raw.githubusercontent.com/tikv/minitrace-rust/master/etc/img/head-benchmark.svg)
 
 Features:
 
@@ -128,6 +128,7 @@ Feel free to open a PR and add your projects here:
 - [Conductor](https://github.com/the-guild-org/conductor): Open-source GraphQL Gateway
 - [Apache OpenDAL](https://github.com/apache/opendal): A data access layer for various storage
 - [Databend](https://github.com/datafuselabs/databend): Cost-Effective alternative to Snowflake
+- [foyer](https://github.com/mrcroxx/foyer): Hybrid in-memory and disk cache in Rust
 
 ## FAQ
 
diff --git a/minitrace/src/span.rs b/minitrace/src/span.rs
index e1bbed7f..dd0cb7cc 100644
--- a/minitrace/src/span.rs
+++ b/minitrace/src/span.rs
@@ -519,11 +519,9 @@ impl Drop for LocalParentGuard {
             let (spans, token) = inner.collector.collect_spans_and_token();
             debug_assert!(token.is_some());
             if let Some(token) = token {
-                if !spans.spans.is_empty() {
-                    inner
-                        .collect
-                        .submit_spans(SpanSet::LocalSpansInner(spans), token);
-                }
+                inner
+                    .collect
+                    .submit_spans(SpanSet::LocalSpansInner(spans), token);
             }
         }
     }
@@ -913,7 +911,7 @@ parent5 []
             .in_sequence(&mut seq)
             .return_const(42_usize);
         mock.expect_submit_spans()
-            .times(4)
+            .times(5)
             .in_sequence(&mut seq)
             .withf(|_, collect_token| collect_token.len() == 1 && collect_token[0].collect_id == 42)
             .returning({