Improvements to speed and stability for the Spring 2009 UDL release

• Save student snapshots online, download only when needed.
  • The greatest cause of the slow speeds seen by students at schools is the large number of snapshots (lab book entries) that the student must download and upload every time they start or save an activity. The new version of UDL will save these images to a different location, outside of the student work. These images can then be downloaded slower, only when required. This will speed up starting for those students, and will also reduce the network load, which will speed up loading for all students. Timeline: One week from 2/16/2009
• Commonly downloaded resources now stored in Java cache.
  • The most commonly used images and other files will now downloaded just once, when the network administrator updates to the most recent version of the UDL program. When the students run the activities, these images and files will never need to be downloaded. This will speed up starting for those students, and will also reduce the network load, which will speed up loading for all students.
• Prevent multiple activity windows from opening.
  • Many cases of student data being lost are caused by students having multiple activity windows open. The extra windows, with little or no student work on them, can sometimes overwrite the earlier work when they are closed and saved. The UDL portal will be set so that it is impossible to open multiple activity windows.
• Improve stability of Concord servers.
  • Some problems with speed and saving were caused by the severs at Concord being overloaded with too much data at once. Large improvements have been made to this, by improving the way that the data is processed by the servers, and by adding 2 GB of memory to the servers used.