Changes between Version 3 and Version 4 of ValidationSummary

Timestamp:

Jun 10, 2008, 9:27:09 AM (17 years ago)

Author:

davea

Comment:

--

ValidationSummary

@@ -63 +63 @@
 === Eliminate discrepancies ===
 
-By selecting the right compiler, compiler options, and math libraries,
-it may be possible to eliminate numerical discrepancies.
+It may be possible to eliminate numerical discrepancies.
+To do so you'll need to select appropriate compiler, compiler options, and math libraries,
+and to make sure that your checkpoint files are full precision.
+
 This lets you do bitwise comparison of results.
 However, it is difficult and generally reduces the performance of your application.
@@ -76 +78 @@
 
 === Homogeneous replication ===
-There are
-                        may bound credit
-                redundancy
-                        exact match
-                                exact computation
-                                        sixtrack example: compiler,
-                                                compiler options (disable DP hardware),
-                                                numerical libraries
-                                homogeneous redundancy
-                                exact checkpointing
-                        fuzzy matching
+
+With this variant of replication,
+once an instance of a job has been sent to a host,
+additional instances are sent only to hosts that are "numerically equivalent"
+(i.e. that will return bit-identical results).
+
+The notion of "numerical equivalence" depends on your application
+and how it was compiled.
+BOINC supplies two pre-defined equivalence relations, "coarse" and "fine".
+Use either of these ("coarse" is preferable, if it's fine enough for your app)
+or define your own if needed.
+
+== Adaptive replication ==
+
+This is a refinement of the replication policy.
+It randomly decides whether to replicate jobs,
+based on the measured error rate of hosts.
+If the first instance of a job is sent to a host with a low error rate,
+then with high probability no further instances will be sent.
+
+Adaptive replication is independent of the comparison policy;
+you can use it with either bitwise comparison,
+fuzzy comparison, or homogeneous replication.