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-rw-r--r--docs/FAQ.md40
-rw-r--r--include/afl-fuzz.h9
2 files changed, 42 insertions, 7 deletions
diff --git a/docs/FAQ.md b/docs/FAQ.md
index 9275eb94..242a379b 100644
--- a/docs/FAQ.md
+++ b/docs/FAQ.md
@@ -29,8 +29,8 @@ If you find an interesting or important question missing, submit it via
   which then implemented their own research and features, making it now by far
   the most flexible and feature rich guided fuzzer available as open source. And
   in independent fuzzing benchmarks it is one of the best fuzzers available,
-  e.g., [Fuzzbench
-  Report](https://www.fuzzbench.com/reports/2020-08-03/index.html).
+  e.g.,
+  [Fuzzbench Report](https://www.fuzzbench.com/reports/2020-08-03/index.html).
 </p></details>
 
 <details>
@@ -103,6 +103,42 @@ If you find an interesting or important question missing, submit it via
   to itself, this too would be an edge.
 </p></details>
 
+<details>
+  <summary id="should-you-ever-stop-afl-fuzz-minimize-the-corpus-and-restart">Should you ever stop afl-fuzz, minimize the corpus and restart?</summary><p>
+
+  To stop afl-fuzz, minimize it's corpus and restart you would usually do:
+
+  ```
+  Control-C  # to terminate afl-fuzz
+  $ afl-cmin -T nproc -i out/default/queue -o minimized_queue -- ./target
+  $ AFL_FAST_CAL=1 AFL_CMPLOG_ONLY_NEW=1 afl-fuzz -i minimized_queue -o out2 [other options] -- ./target
+  ```
+
+  If this improves fuzzing or not is debated and no consensus has been reached
+  or in-depth analysis been performed.
+
+  On the pro side:
+    * The queue/corpus is reduced (up to 20%) by removing intermediate paths
+      that are maybe not needed anymore.
+
+  On the con side:
+    * Fuzzing time is lost for the time the fuzzing is stopped, minimized and
+      restarted.
+
+  The the big question:
+    * Does a minimized queue/corpus improve finding new coverage or does it
+      hinder it?
+
+  The AFL++ team's own limited analysis seem to to show that keeping
+  intermediate paths help to find more coverage, at least for afl-fuzz.
+
+  For honggfuzz in comparison it is a good idea to restart it from time to
+  time if you have other fuzzers (e.g: AFL++) running in parallel to sync
+  the finds of other fuzzers to honggfuzz as it has no syncing feature like
+  AFL++ or libfuzzer.
+
+</p></details>
+
 ## Targets
 
 <details>
diff --git a/include/afl-fuzz.h b/include/afl-fuzz.h
index 1f89bbd8..3dfd2b2c 100644
--- a/include/afl-fuzz.h
+++ b/include/afl-fuzz.h
@@ -158,6 +158,7 @@ struct queue_entry {
 
   u8 colorized,                         /* Do not run redqueen stage again  */
       cal_failed;                       /* Calibration failed?              */
+
   bool trim_done,                       /* Trimmed?                         */
       was_fuzzed,                       /* historical, but needed for MOpt  */
       passed_det,                       /* Deterministic stages passed?     */
@@ -169,17 +170,15 @@ struct queue_entry {
       disabled;                         /* Is disabled from fuzz selection  */
 
   u32 bitmap_size,                      /* Number of bits set in bitmap     */
-      fuzz_level,                       /* Number of fuzzing iterations     */
-      n_fuzz_entry                      /* offset in n_fuzz                 */
 #ifdef INTROSPECTION
-      ,
       stats_selected,                   /* stats: how often selected        */
       stats_skipped,                    /* stats: how often skipped         */
       stats_finds,                      /* stats: # of saved finds          */
       stats_crashes,                    /* stats: # of saved crashes        */
-      stats_tmouts                      /* stats: # of saved timeouts       */
+      stats_tmouts,                      /* stats: # of saved timeouts       */
 #endif
-      ;
+      fuzz_level,                       /* Number of fuzzing iterations     */
+      n_fuzz_entry;                      /* offset in n_fuzz                 */
 
   u64 exec_us,                          /* Execution time (us)              */
       handicap,                         /* Number of queue cycles behind    */