diff --git a/benches/my_bench.rs b/benches/my_bench.rs
index 6a068db..aa1232e 100644
--- a/benches/my_bench.rs
+++ b/benches/my_bench.rs
@@ -8,7 +8,7 @@ fn do_log() {
     debug!("debug");
 }
 fn criterion_benchmark(c: &mut Criterion) {
-    let _guard = default();
+    let _guard = default(false, false);
     c.bench_function("log", |b| b.iter(|| do_log()));
 }
 
diff --git a/examples/tracing-log/main.rs b/examples/tracing-log/main.rs
index c888057..b1e08db 100644
--- a/examples/tracing-log/main.rs
+++ b/examples/tracing-log/main.rs
@@ -2,6 +2,6 @@ use rolling_file::default;
 mod submod;
 
 fn main() {
-    let _guard = default();
+    let _guard = default(false, false);
     submod::do_record();
 }
diff --git a/src/lib.rs b/src/lib.rs
index f5b8d0a..1e67cf9 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -76,13 +76,18 @@ impl FileRoller {
         for entry in fs::read_dir(&self.base_dir)? {
             let entry = entry?;
             let metadata = entry.metadata()?;
-            if metadata.is_dir() {
+
+            if !metadata.is_file() {
                 continue;
             }
+
             if let Some(filename) = entry.file_name().to_str() {
                 let fnames: Vec<_> = filename.split(".").collect();
-                if fnames.len() == 2 {
-                    if let Ok(dt) = NaiveDateTime::parse_from_str(fnames[0], "%Y%m%d%H%M%S") {
+                if fnames.len() == 2 && fnames[1] == "log" {
+                    if let Ok(dt) = NaiveDateTime::parse_from_str(
+                        &get_filename_format(fnames[0], &self.period),
+                        "%Y%m%d%H%M%S",
+                    ) {
                         let dt = dt + duration;
                         let created_at = get_gap_with_time(&self.period, dt);
                         if self.current_gap >= created_at {
@@ -114,6 +119,17 @@ impl FileRoller {
     }
 }
 
+// change the filename to the "20060102000000" format
+fn get_filename_format(fname: &str, period: &PeriodGap) -> String {
+    match *period {
+        PeriodGap::Secondly => fname.to_string(),
+        PeriodGap::Minutely => format!("{}00", fname),
+        PeriodGap::Hourly => format!("{}0000", fname),
+        PeriodGap::Daily => format!("{}000000", fname),
+        PeriodGap::Monthly => format!("{}01000000", fname),
+    }
+}
+
 impl io::Write for FileRoller {
     fn write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
         if let Err(e) = self.rollover() {
@@ -207,14 +223,16 @@ pub fn new_log<P: AsRef<Path>>(
     maxfile: usize,
     period: PeriodGap,
     level: tracing::Level,
+    with_filename: bool,
+    with_line_number: bool,
 ) -> tracing_appender::non_blocking::WorkerGuard {
     let timefmt = format_description!("[year]-[month]-[day]T[hour]:[minute]:[second]");
     let timer = OffsetTime::new(offset!(+8), timefmt);
     let roller = FileRoller::new(path, maxfile, period);
     let (writer, guard) = tracing_appender::non_blocking(roller);
     tracing_subscriber::fmt()
-        .with_line_number(true)
-        .with_file(true)
+        .with_line_number(with_line_number)
+        .with_file(with_filename)
         .with_writer(writer)
         .with_max_level(level)
         .with_timer(timer)
@@ -224,23 +242,42 @@ pub fn new_log<P: AsRef<Path>>(
     guard
 }
 
-pub fn default() -> tracing_appender::non_blocking::WorkerGuard {
-    new_log("./.output", 7, PeriodGap::Daily, tracing::Level::DEBUG)
+pub fn default(
+    with_filename: bool,
+    with_line_number: bool,
+) -> tracing_appender::non_blocking::WorkerGuard {
+    new_log(
+        "./.output",
+        7,
+        PeriodGap::Daily,
+        tracing::Level::DEBUG,
+        with_filename,
+        with_line_number,
+    )
+}
+
+pub fn default_second() -> tracing_appender::non_blocking::WorkerGuard {
+    new_log(
+        "./.output",
+        7,
+        PeriodGap::Secondly,
+        tracing::Level::DEBUG,
+        false,
+        false,
+    )
 }
 
 #[cfg(test)]
 mod tests {
     use super::*;
-    use std::io::Write;
     use std::thread;
-    use std::time::Duration;
 
     #[test]
     fn it_works() -> io::Result<()> {
-        let mut roller = FileRoller::new("output", 8, PeriodGap::Secondly);
-        for _ in 0..200 {
-            let _ = roller.write_all("hello\n".as_bytes())?;
-            thread::sleep(Duration::from_millis(100));
+        let _guard = default_second();
+        for _ in 0..10 {
+            tracing::debug!("hello1");
+            thread::sleep(Duration::from_millis(1000));
         }
         Ok(())
     }