Changes between Version 1 and Version 2 of DbPurge

Timestamp:

May 4, 2007, 10:44:01 AM (17 years ago)

Author:

davea

Comment:

--

DbPurge

@@ -2 +2 @@
 
 As a BOINC project operates, the size of its workunit and result tables increases. Eventually they become so large that adding a field or building an index may take hours or days.
-
 To address this problem, BOINC provides a utility '''db_purge''' that writes result and WU records to XML-format archive files, then deletes them from the database.
-
 Workunits are purged only when their input files have been deleted. Because of BOINC's file-deletion policy, this implies that all results are completed. So when a workunit is purged, all its results are purged too.
 
-Run db_purge from the project's bin/ directory. It will create an archive/ directory and store archive files there.
+db_purge creates an archive/ directory and store archive files there.
 
 db_purge is normally run as a daemon, specified in the [ProjectConfigFile config.xml] file. It has the following command-line options: 
@@ -23 +21 @@
  '''-d N'''::
         Set logging verbosity to N (1,2,3)
+
+== Recording credited jobs ==
+
+You may want to keep a record of which user returned a valid result for each workunit
+(e.g. so that you can give them credit for specific discoveries).
+If you use db_purge, this information is removed from the database;
+it can be extracted from the XML archives, but it's slow.
+
+Alternatively, you can store the user/workunit association in
+a separate table called '''credited_job'''.
+This records in this table are small - they store only a user ID
+and a 64-bit integer which is taken from the workunit's 'opaque' field
+(typically an index in a separate database).
+By default, the table has indices that allow you to efficiently
+enumerate workunits for a given user and users for a given workunit.
+
+To use the credited_job table, pass the -update_credited_job flag
+to your validator.
+
 
 == Archive file format ==