Title: CPSC 601.38: Project Brainstorming Session
1CPSC 601.38Project Brainstorming Session
- Carey Williamson
- Department of Computer Science
- University of Calgary
2PROJECT OVERVIEW
- A typical course project might involve
- design/build/obtain appropriate testbed,
environment, or platform for your project - extend/customize as needed
- obtain relevant data/measurements needed
- design suitable experiment clear goal, identify
factors, levels, performance metrics - obtain and present (new/interesting) results
3Some Data Sets and Traces
- Web server access logs (1996)
- Web proxy access logs (1998)
- MPEG video traces (20 x 40,000 frames)
- ISP measurements (4 traces, 1-2 minutes)
- FrameRelay/ATM traces (5 traces)
- Bellcore Ethernet LAN trace (1989)
- TCP/IP packet traces (LBL, 24 hours, 1.8M)
- See also the Internet Traffic Archive
4Some Available Simulators
- ATM-TN simulator (ATM cell-level)
- Clustered Web server simulator (dws)
- Web proxy caching hierarchies (Muda)
- Distributed Web proxy simulator
- IP-TN simulator (U of C)
- IP-TNE (emulator) (U of C)
- LBLs ns-2 simulator (TCP packet level)
5Some Useful Tools
- Synthetic Web proxy workload generation
- Web client traffic model (mosaic, 1995)
- LRD traffic analysis (R/S, V-T, AC, etc)
- GUI for traffic modeling/analysis (synTraff)
- Wavelet-based traffic model (Ram)
- Synthetic MPEG video trace generation
- SimKit programming language (UofC)
6Issues and Ideas
- Improving/extending ProWGen
- temporal locality document mods scaling
- Web proxy caching hierarchies
- Hierarchical vs distributed caching
- Web response time modeling
- Improving network TCP flow model (dws)
- Wavelet-based traffic forecasting
- Wavelength assignment in WDM networks
71. ATM-TN System Overview
Input Data Set
ATM-T
ATM MF
ATM-N
TMF
SimKit
ESS
WarpKit
SMTW
Output Data Set
workstation
UNIX
Report Generation Scripts
Hardware SPARC, KSR, SGI
Report
8CBR Poisson Ethernet JPEG/MPEG Web
TCP/IP/AAL5 ABR
Traffic Models
ATM MF
TMF
Switch and Network Models
SimKit
ESS
WarpKit
WaiKit
SMTW
UNIX Operating System
X
Sequential UNIX Workstations (SGI, SPARC, DEC,
HP) Parallel SGI Power Challenge, SPARC 1000
92. Distributed Web Server Model
1
File Server
2
3
Cache
Dispatcher (Front End)
Manager
N
Object Store
Web Clients
Server Nodes
10Server Parameters
- Num server nodes
- Mem cache size
- Disk cache size
- Cache replacement policy for each (LRU, LFU,
SIZE, DUAL) - Comm. latency
- Cache consistency
- Dispatch policy (DNS, RR, Redirect, Load)
- Request distribution policy (requests, bw, conns,
affinity, ...) - Server bandwidth
- Per-request bandwidth
- BW scaling model
11Performance Metrics
- Load balancing
- requests
- bytes
- bandwidth
- connections
- clients
- Relative improvement versus RR, Rand, etc
- Cache performance
- document hit rate
- byte hit rate
- Comm. overhead
- Avg response time
- Avg inflation factor
- Others...
123. Web Proxy Caching Model
Web Servers
Web Clients
13Hierarchical Proxy Caching Simulation Model
Web Servers
Web Clients
14Factors and Levels
- Cache size
- Cache Replacement Policy
- Recency-based LRU
- Frequency-based LFU-Aging
- Size-based GD-Size
- Workload Characteristics
- One-timers, Zipf slope, tail index, correlation,
temporal locality model
15ProWGen Conceptual View
ProWGen Software
Input Parameters
Synthetic Workload
1
Z
a
c
L
16Key Workload Characteristics
- One-timers (60-70 useless!!!)
- Zipf-like document referencing popularity
- Heavy-tailed file size distribution (i.e., most
files small, but most bytes are in big files) - Correlations (if any) between document size and
document popularity (debate!) - Temporal locality (temporal correlation between
recent past and near future references) Mahanti
et al. 2000