QPipe

Goal

 Re-engineer relational engines to optimize resource usage in large-scale installations

Details

 Relational execution engines typically treat concurrent queries as independent tasks, evaluating every plan in isolation. Reusing in-memory data pages across different queries is the job of the buffer pool manager, which can only set policy and not actively participate in the query evaluation process. Reusing common computations across concurrent queries comes at the cost of materializing views and assumes prior workload knowledge. The challenge is to exploit all opportunities for reusing both data and computation across concurrent queries transparently, without introducing additional costs or requiring prior knowledge.

Future Goals

 The next goal is to deploy the staged system in multi-processor environments and develop query scheduling algorithms to minimize response time while maintaining high resource utilization.

Related Documenation
[ICDE06]

Simultaneous Pipelining in QPipe: Exploiting Work Sharing Opportunities Across Queries

  Kun Gao, Stavros Harizopoulos, Ippokratis Pandis, Vladislav Shkapenyuk, Debabrata Dash, Nikos Hardavellas, Ryan Johnson, Naju Mancheril, and Anastassia Ailamaki.
Demonstration, in Proceedings of the 22nd ICDE, Atlanta, GA, April 2006.
PDF [196k] / Poster [540k]

[IEEE05]

StagedDB: Designing Database Servers for Modern Hardware

  Stavros Harizopoulos and Anastassia Ailamaki.
In IEEE Data Engineering Bulletin, 28(2):11-16, June 2005.
PDF [41k]

[SIGMOD05]

QPipe: A Simultaneously Pipelined Relational Query Engine

  Stavros Harizopoulos, Vladislav Shkapenyuk and Anastassia Ailamaki.
In proceedings of the 24th SIGMOD, Baltimore, MD, June 2005
PDF [295k]

[CIDR03]

A Case for Staged Database Systems

  Stavros Harizopoulos and Anastassia Ailamaki.
In proceedings of the 1st CIDR, Asilomar, CA, January 2003.
PDF [153k]

[TR02]

Affinity Scheduling in Staged Server Architectures

  Stavros Harizopoulos and Anastassia Ailamaki.
Carnegie Mellon University Technical Report CMU-CS-02-113, March 2002.
PDF [186k]