Changes between Version 14 and Version 15 of BossaOverview

Timestamp:

Jul 29, 2008, 1:41:39 PM (16 years ago)

Author:

davea

Comment:

--

BossaOverview

@@ -22 +22 @@
 Distributed thinking projects have widely varying properties
 and hence different requirements.
-Bossa's design philosophy is to provide '''mechanisms''',
-and leave it up to the projects to define the '''policies'''.
-This is done using the following techniques:
+Bossa doesn't directly provide all needed features;
+rather, it makes it easy for you to implement what you need.
+The division of labor is as follows:
 
-== The diverse requirements of distributed thinking ==
+ * Bossa provides '''mechanisms'''. It provides all the database (MySQL) support.
+ * You (the project) define the '''policies''' by writing PHP functions; you need to have basic knowledge of PHP to use Bossa.
 
+Some of these mechanisms and policies are as follows.
 
-First, they may require different ''distribution policies'',
+== Job and result representation ==
+
+The data needed to display a job may include various filenames, numbers, etc.
+This info is stored in a PHP structure
+that you create when you generate the job.
+Bossa stores this in a serialized (textual) from in the database.
+When a job is to be displayed to a volunteer,
+Bossa calls your "job display function", passing it this structure.
+
+Similarly, the results of a completed job are stored in a PHP structure
+defined by your application.
+
+== Job distribution policy ==
+
+Applications may require different ''job distribution policies'',
 i.e. different orders in which jobs are distributed.
 Consider the two cases:
@@ -47 +63 @@
 The longer the project runs, the more jobs are finished.
 
-Second, projects may want to assess the ability of each volunteer,
+Bossa's mechanism is that each job has a floating-point priority,
+and jobs are issued in order of decreasing priority.
+The manipulation of these priorities is up to you.
+Policies are encoded in PHP '''project policy functions''' that are invoked at various points
+(e.g., when jobs are issued, when they complete, and when they time out).
+
+== Volunteer assessment ==
+
+Projects may want to assess the ability of each volunteer,
 and use this to determine how many replicas of each job to perform.
 Several factors might contribute to the ability estimate:
@@ -60 +84 @@
  * For more complex tasks, ability could have arbitrarily many dimensions.
 
-Third, there are various way in which "experts" might be used.
+Bossa lets you associate an arbitrary PHP structure with each volunteer.
+This can be initialized and updated however you want.
+
+Bossa provides a '''calibration job''' mechanism;
+jobs can be designated as calibration jobs,
+and Bossa can be instructed to randomly mix a given rate of calibration jobs into the job stream.
+
+== Use of experts ==
+
+There are various way in which "experts" might be used.
 Two general possibilities:
 
@@ -69 +102 @@
  For example, non-experts might look for features, while experts classify them.
 
-== How Bossa addresses these requirements ==
-
-
-
- * Project-specific information about jobs and volunteers is stored in '''project data''' fields.  These are PHP objects whose structure is determined by the project.  Bossa stores them in a textual form in the database.
- * Project-specific policies are encoded in PHP '''project policy functions''' that are invoked at various points (e.g., when jobs are issued, when they complete, and when they time out).
-
-The mechanisms provided by Bossa include:
-
- * Jobs can be designated as '''calibration jobs''', and Bossa can be instructed to randomly mix a given rate of calibration jobs into the job stream.
- * The order in which jobs are issued is determined by a floating-point priority.  The manipulation of these priorities is up to the project.
- * Users can be assigned integer '''levels''', in which case each job has a vector of priorities, one per level.
-
-This framework enables all of the examples listed above (and others not yet conceived of)
-to be implemented with a small amount of PHP programming.
+Bossa provides the following mechanism:
+volunteers can be assigned integer '''levels'''.
+Each job has a vector of priorities, one per level.
+Jobs are sent to a given volunteer in order of decreasing level-specific
+priority.