Optimized Data Migration within a System of Linked Medical Research Databases By Jared Christopherson U. of Connecticut

Problem to Address Medical research requires connections to multiple hospitals, institutions, or online databases Data must be compiled manually Process is time-consuming

General Project Goal

Project Goals: Present data as though from a single source Give the researcher flexibility with viewing the data Optimize data flow with site caching

Real World Issue: Data Formatting

Solution: Master Template

Master Templates and Display Templates

Basic Functionality Provides a simple search for users Researchers have the option of selecting a pre-set Display Template to only display data relevant to their needs Queries each database individually according to the Master Template Returns results and (optionally) compiles them into a single list Use AJAX to return results for each database

Caching and Optimization Goal: researchers should have fastest access possible to the info they seek X-RAY or MRI images could be 2-5Mb in size each What if researchers in the US consistently need access to data on a server in Asia? Local access would be fastest

Caching Goal

Caching and Optimization: Possible Solutions Move everything to a central server Move records around as they are accessed Cache everything Cache databases based on usage

Query and Result Set – No Caching

Caching Process

Caching Complete

Region Caching

Database Caching Queue – What to cache? For each region, determines the top external servers used based on a percentage of queries

Database Caching Queue Need a method to determine the most heavily requested external databases for each region Track statistics: Convert IP address -> region whenever a user performs a search Increment result count for the record that keeps track of the region ID and database ID

DB Queue to Cache

Caching and Optimization: Where to cache data Real-world constraints allow_cache supersite bandwidth cache_size

Caching and Optimization: Script Process Runs at frequency set by admin This process continues for each region with the program assigning data to servers with progressively lower bandwidth and cache_size scores until all the server space from that region is exhausted

Caching and Optimization: Script Process At the end, each region should have as many local copies of the most frequently requested databases as possible Cached copies are read-only

Further Work and Improvements Allow different types of databases (DAL) Remove overlapping data Script to determine when individual caches need to be updated