diff --git a/bin/mtag/sleep.py b/bin/mtag/sleep.py
new file mode 100644
index 00000000..5fa39152
--- /dev/null
+++ b/bin/mtag/sleep.py
@@ -0,0 +1,8 @@
+#!/usr/bin/env python
+
+import time
+import random
+
+v = random.random() * 6
+time.sleep(v)
+print(f"{v:.2f}")
diff --git a/copyparty/up2k.py b/copyparty/up2k.py
index 669f43f0..aeaaee9e 100644
--- a/copyparty/up2k.py
+++ b/copyparty/up2k.py
@@ -469,7 +469,7 @@ class Up2k(object):
                     n_tags = self._tag_file(c3, *args)
                 else:
                     mpool.put(["mtag"] + args)
-                    n_tags = self._flush_mpool(c3)
+                    n_tags = len(self._flush_mpool(c3))
 
                 n_add += n_tags
                 n_buf += n_tags
@@ -490,10 +490,10 @@ class Up2k(object):
 
     def _flush_mpool(self, wcur):
         with self.mutex:
-            ret = 0
+            ret = []
             for x in self.pending_tags:
                 self._tag_file(wcur, *x)
-                ret += 1
+                ret.append(x[1])
 
             self.pending_tags = []
             return ret
@@ -552,6 +552,8 @@ class Up2k(object):
         t_prev = time.time()
         n_prev = n_left
         n_done = 0
+        to_delete = {}
+        in_progress = {}
         while True:
             with self.mutex:
                 q = "select w from mt where k = 't:mtp' limit ?"
@@ -559,9 +561,6 @@ class Up2k(object):
                 warks = [x[0] for x in warks]
                 jobs = []
                 for w in warks:
-                    q = "delete from mt where w = ? and k = 't:mtp'"
-                    cur.execute(q, (w,))
-
                     q = "select rd, fn from up where substr(w,1,16)=? limit 1"
                     rd, fn = cur.execute(q, (w,)).fetchone()
                     rd, fn = s3dec(rd, fn)
@@ -573,15 +572,32 @@ class Up2k(object):
 
                     if ".dur" not in have:
                         # skip non-audio
+                        to_delete[w] = True
                         n_left -= 1
                         continue
 
+                    if w in in_progress:
+                        continue
+
                     task_parsers = {
                         k: v for k, v in parsers.items() if k in force or k not in have
                     }
                     jobs.append([task_parsers, None, w, abspath])
+                    in_progress[w] = True
 
-            n_done += self._flush_mpool(wcur)
+            done = self._flush_mpool(wcur)
+
+            with self.mutex:
+                for w in done:
+                    to_delete[w] = True
+                    in_progress.pop(w)
+                    n_done += 1
+
+                for w in to_delete.keys():
+                    q = "delete from mt where w = ? and k = 't:mtp'"
+                    cur.execute(q, (w,))
+
+                to_delete = {}
 
             if not warks:
                 break
@@ -612,8 +628,12 @@ class Up2k(object):
             with self.mutex:
                 cur.connection.commit()
 
-        self._stop_mpool(mpool, wcur)
+        done = self._stop_mpool(mpool, wcur)
         with self.mutex:
+            for w in done:
+                q = "delete from mt where w = ? and k = 't:mtp'"
+                cur.execute(q, (w,))
+
             cur.connection.commit()
             if n_done:
                 self.vac(cur, db_path, n_done, 0, sz0)
@@ -654,13 +674,15 @@ class Up2k(object):
             mpool.put(None)
 
         mpool.join()
-        self._flush_mpool(wcur)
+        done = self._flush_mpool(wcur)
         if WINDOWS and False:
             nah = open(os.devnull, "wb")
             wmic = f"processid={os.getpid()}"
             wmic = ["wmic", "process", "where", wmic, "call", "setpriority"]
             sp.call(wmic + ["below normal"], stdout=nah, stderr=nah)
 
+        return done
+
     def _tag_thr(self, q):
         while True:
             task = q.get()
diff --git a/docs/notes.sh b/docs/notes.sh
index 9d32450a..76071d3f 100644
--- a/docs/notes.sh
+++ b/docs/notes.sh
@@ -78,6 +78,16 @@ time sqlite3 up2k.db 'select mt1.w from mt mt1 inner join mt mt2 on mt1.w = mt2.
 cat warks | while IFS= read -r x; do sqlite3 up2k.db "delete from mt where w = '$x'"; done
 
 
+##
+## media
+
+# split track into test files
+e=6; s=10; d=~/dev/copyparty/srv/aus; n=1; p=0; e=$((e*60)); rm -rf $d; mkdir $d; while true; do ffmpeg -hide_banner -ss $p -i 'nervous_testpilot - office.mp3' -c copy -t $s $d/$(printf %04d $n).mp3; n=$((n+1)); p=$((p+s)); [ $p -gt $e ] && break; done
+
+-v srv/aus:aus:r:ce2dsa:ce2ts:cmtp=fgsfds=bin/mtag/sleep.py
+sqlite3 .hist/up2k.db 'select * from mt where k="fgsfds" or k="t:mtp"' | tee /dev/stderr | wc -l
+
+
 ##
 ## vscode