User's guide to the Reliability Estimation System Testbed (REST)

NASA Technical Memorandum

User's Guide to the Reliability Testbed (REST)

David Daniel Adam

June

107596

Estimation

System

M. Nicol L. Palumbo Rifldn

1992

(,IASA-TH-1975_6) T_ , Ch[j]

is dead,

: RecvCHMsg();

FAILED

_ 4,

in the STATIC

! is logical

ALIVE

section

negation,

= 8 of

REST

model

" is bit-wise

exclusive

//

I is bit-wise

OR

, R is bit-wise

AND

//

II is logical

OR

, RR

AND

//

The

interface

j-O,l

;

// Constants // are declared

j set

is logical

fails

FailEvt:IF(!(GetState(OpState)

R FAILED))

TKANTO

{ int OS - GetState(OpState); PutState(OpState,OSIFailed); SendYalue(Sys,FAILED); } BY ICFailureRate;

// The

interface

RepairEvt:

repairs

itself

IF(GetState(OpState) { inr

R FAILED)

TRANTO

OS - GetState(OpSrate); PutSrate(OpState,

OS k'FAILED);

SendValue(Sys,ALIVE); } BY FAST

// The

system

DeathEvt:

ICRepairRate;

is in a failure

DEATHIF

state

((GetSta_e(OpS_ate) R FAILED) Ra GetS_ate(CH[O].Status) -- FAILED GetState(CH[1].Sta_us)

CODE

{ void

_R

.5 FAILED

);

RecvCHMsg(msg,who) int *msg,who; {int

OS - GetState(OpState);

// create int WhoBit

bitmask

describing

if(.msE--FAILED)

// record

PutState(OpS_ate, else // PutState(OpStat, } // end of CODE

].

caller

- 1 O) PuzState(IntManState,VULNERABLE); if (gffi=O)PuzState(IntManState,FAIL); }/IEval IIIMESS //

When

an Interface changes state, void Imess(msg,who) int *msg,who; { In%erfaceManager_Eval();

The

parent

manager

must

reevaluate

}

Listing

9h.

RML

Model

of

Quad

Processors (contd)

plus

Interfaces:

InterfaceManager

I[3])

86

CHAPTER

5.

LISTINGS

//RECEFFECT // // //

This recovery is pretty simple. Interfaces which are INUSE and have E_ROR are REMOVED. If I[O] fails, I[1] is activated and if I[33 fails, I[2] void RecEffect() { int for

s,i; (i=O; i