Data Management

Q-Cop: Avoiding Bad Query Mixes to Minimize Client Timeouts Under Heavy Loads

Free registration required

Executive Summary

In three-tiered web applications, some form of admission control is required to ensure that throughput and response times are not significantly harmed during periods of heavy load. The authors propose Q-Cop, a prototype system for improving admission control decisions that considers a combination of the load on the system, the number of simultaneous queries being executed, the actual mix of queries being executed, and the expected time a user may wait for a reply before they or their browser give up (i.e., time out). Using TPC-W queries, they show that the response times of different types of queries can vary significantly depending not just on the number of queries being processed but on the mix of other queries that are running simultaneously.

  • Format: PDF
  • Size: 454.49 KB