Maximizing Performance and Scalability with IBM WebSphere

R

RAM disk technology

function of, 130

raw file systems vs. nonraw file systems, 435

recvspace attribute

setting for TCP send and receive buffer, 270

redundancy

five progressive levels of in an organization, 36 “39

redundancy paths

recommended for WebSphere-to-database networking, 143

regedit. See Registry Editor tool (regedit)

Registry Editor tool (regedit)

changing setting within the registry with, 252 “255

changing the TCPTimedWaitDelay value with, 254 “255

relational database platform

key points about sizing, 431 “435

Remote Method Invocation (RMI) connections

teardown of vs. lightweight connections, 270 “271

repositories and data stores

in WebSphere 5, 77 “78

repository database failover

configuration issues in WebSphere 4, 356 “358

resiliency. See availability

Resource Analyzer tool

checking for I/O time-outs with, 392 “393

example screen, 514

features from a profiling perspective, 515

function of, 513 “515

vs. HPjmeter and JProbe tools, 515

for monitoring and testing TIME_WAIT state, 390

for monitoring operational aspects of applications, 244

for monitoring thread values in WebSphere 4, 387 “389

response time

decrease in perceived for user or customer, 8 “9

response times

effect of concurrent and registered users on, 236

example of an end-to-end measurement, 235

testing of for an application, 234 “236

RetryInterval

setting in WebSphere 5, 331 “332

tuning, 325

Return on Investment (ROI), 19

an overview, 23 “24

vs. Total Cost of Ownership (TCO), 23

RISC-based processors

cost of vs. CISC or x86 processors, 97

RISC-based UltraSPARC processors vs. Complex Instruction Set Computing (CISC)-based processors, 96

RMI-IIOP, 168

vs. Java IIOP, 456

ROI. See Return on Investment (ROI)

round- robin load distribution model, 317 “318

Route directive section

in the HTTP plug-in configuration file, 57 “58

RRDtool

monitoring tool (graphing), 245

RS64 processor family

architecture and function of, 112 “113

rs.close() command

closing the result set object with, 421

rules

building block for WebSphere application environments, 155 “157

Run queue

in Unix, 476