Changes between Version 18 and Version 19 of BasicApi

Timestamp:

Jan 8, 2009, 11:00:12 AM (16 years ago)

Author:

davea

Comment:

--

BasicApi

@@ -94 +94 @@
 
 `boinc_time_to_checkpoint()` is fast, so it can be called frequently (hundreds or thousands of times a second).
+
+If you're using replication, make sure your application generates the same results
+regardless of where and how often it restarts.
+This requires:
+ * In writing the checkpoint file, use conversion codes that don't lose precision; e.g., use %e for doubles.
+ * If your app uses random numbers, save and restore the state of the RNG.  You can do this by surrounding every boinc_time_to_checkpoint() with the following:
+{{{
+int x = rand();
+if (boinc_time_to_checkpoint()) {
+   ...
+}
+srand(x);
+}}}
+Write x to the checkpoint file,
+and do a srand(x) when restarting from a checkpoint.
 
 == Critical sections ==