Analysis of Database Workloads on Modern Processors

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Analysis of Database Workloads on Modern
Processors
Advisor Prof. Shan Wang P.h.D student Dawei
Liu
Key Laboratory of Data Engineering and
Knowledge Engineering MOE
School of Information Renmin University of China
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Outlines

• 1. Background
• 2. Motivation
• 3. Our research work
• 4. Future works

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Background

• LAMA Project

• rgle Scale Data nagement

• La Ma

• Joint research with HP Lab China

• Goal
• Advanced issues of Massively Parallel Processing
  (MPP) databases
• Architecture and design aspects
• Next generation memory oriented DB

My Focus
4
Outlines

• 1. Background
• 3. Our research
• 4. Future works

2. Motivation
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Motivation

• Continued evolution of hardware
• Processor

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Motivation(cont.)

• Memory

Larger and Larger
Flash Memory
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Cont.

• Traditional research
• Dedicate to I/O optimization
• Fail to utilize processor resources efficiently

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Cont.

• Modern processors (Itanium II)
• multi-level memory hierarchies
• superscalar out-of-order execution
• multi-threading
• multi-cores

Create opportunity for database performance
improve.
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Cont.

• Object
• Accurately characterizing workload behavior on
  modern processor
• Find out the bottleneck
• Benefit
• Identify a set of characteristics
• performance optimization

Detailed issues ?
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My P.h. D Track

• (1) Accurately characterize the database
  workloads on modern processors
• (2) Investigating the MMDB workloads on modern
  processor
• (3) Developing a specialized benchmark for MMDB

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(1) Processor Issue

• Previous research
• Conlusion
• DBMSs achieve low IPC (instructions-per-cycle)
• Processors are inefficiently used
• Platform
• Intel Pentium II / Pentium Pro
• --------------------------------------------------
  --------------------------------------------------
  ------------------------------------

A. Ailamaki, D. J. DeWitt, M. D. Hill, D. A.
Wood. DBMSs on a Modern Processor Where Does
Time Go? In Proc. VLDB, 1999.
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Cont.

• We are interested in
• DBMS on todays processors
• Itanium II
• AMD Opteron (tm)

Where does 8 years go ?
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(2) Main Memory DB Issue

• Previous research
• DB Disk Resident Databases (DRDB)
• Workload TPC-C

Larger and larger on-chip and off-chip caches
Steady increased RAM
The moved up on the memory hierarchy

• Current problems
• DB Main Memory Databases (MMDB)
• Workload TPC-H (compute intensive)

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(3) MMDB-Oriented Benchmark

• Performance evaluation
• OO1-Benchmark
• OO7-Benchmark

obsolete

• Industrial standards

OLAP
OLTP
TPC Benchmark H
TPC Benchmark C
We found they are not approprite to benchmark MMDB
How to benchmark memory database ?
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Outlines

• 1. Background
• 2. Motivation
• 4. Future works

3. Our research
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Methodology

• Analysis framework
• Experiment study

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Pipeline of modern processors
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Query Execution Time Breakdown

• TQ TC TM TB TR - TOV L
• TC Useful computation time
• TM Stall time because of memory stalls
• TB Branch misprediction overhead
• TR Resource-related stalls
• TOVL Stall time can be overlapped

A. Ailamaki, D. J. DeWitt, M. D. Hill, D. A.
Wood. DBMSs on a Modern Processor Where Does
Time Go? In Proc. VLDB, 1999.
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Execution time components on Itanium II platform
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Experimental setup

• Platform-specific hardware
• Software
• Experimental methodology

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The Hardware Platform

• HP Integrity rx2620-2 server
• Itanium II based server
• Cache

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Cache characteristics
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Software and Methodology

• Calibrator (CWI )
• cache access and miss latency
• main memory access latency
• number of TLB levels
• each levels TLB miss latency

Centrum voor Wiskunde en Informatica National
research institute for mathematics and computer
science in the Netherlands
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Cont.

• Perfsuite (NSCA )

Control hardware counters
Measure 60 event types for the results
Hardware counters
National Center for Supercomputing
Applications (NCSA)
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Stall time components on Itanium II
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Results analysis

• Part one DRDB
• Characterization workload on Itanium II
• OLTP
• OLAP
• Part two MMDB issue
• Characterization of MMDB TPC-H workload
• --------------------------------------------------
  --------------------------------------------------
  -----

• Dawei liu, Shan Wang, Biao Qin, Weiwei Gong
  Characterizing DSS Workloads from the Processor
  Perspective. The International Workshop on
  Database Management and Application over Network
  DBMAN 2007 235-240

• DaweiDawei Liu, Shan Wang, Qiming Chen, Yun Tian,
  Weiwei Gong Main Memory Database TPC-H Workload
  Characterization on Modern Processor, Renmin
  University of China., TR-01, 2007,
  http//deke.ruc.edu.cn/tr/TR 2007-01.

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Memory stall time breakdown
TPC-H Workload on a DRDB
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Index Influence
TPC-H Workload on a DRDB
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Branch Instruction Misprediction
TPC-H Workload on a DRDB
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DRDB vs. MMDB
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Storage Architecture Influence
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Summary

• Characterized workload on Itanium II based
  platform
• Characterized MMDB read optimized workload on
  modern processors
• Compare the workload breakdown of DRDB and MMDB
• Explored the difference of column-oriented and
  row-oriented storage models in CPU and cache
  utilization
• Investigated the index influence at low level

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Outlines

• 1. Background
• 2. Motivation
• 3. Our research

4. Future works
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Future works

• In-depth analysis of the results
• Develop new parallel techniques
• Instruction level parallelism
• MMDB benchmark issue
• The results expected to benefit
• The performance optimization of DBMS
• The architecture of next-generation
  memory-oriented databases.

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The End

• Thanks! Welcome to visit RUC.

Key Laboratory of Data Engineering and
Knowledge Engineering MOE
Dawei Liu School of Information Renmin
University of China
liudawei_at_ruc.edu.cn http//deke.ruc.edu.c
n Tel. [phone]