measureTime

measureTime( 
g_expression ... 
) 
=> l_result

Description

Measures the time needed to evaluate an expression and returns a list with performance data (n_utime, n_stime, n_clockTime, and x_pageFaults) for the executed expressions. This is a syntax form.

• n_utime: The amount of user CPU time, in seconds, spent on the execution of expressions (counted with getrusage()).
• n_stime: The amount of system CPU time, in seconds, spent on the execution of expressions (counted with getrusage()).
• n_clockTime: The clock time used on execution of the expressions (in seconds) (counted with gettimeofday()). This function assumes that the executed expressions do not alter getimeofday() result.
• x_pageFaults: The number of page faults that occurred during the execution of the expressions (counted with gettimeofday()).

Arguments

g_expression

Expression(s) to be evaluated and timed.

Value Returned

l_result

A list with performance data (n_utime, n_stime, n_clockTime, and x_pageFaults) for the executed expressions.

Examples

myList = nil            ; Initializes the variable myList.
measureTime( for( i 1 10000 myList = cons(i myList) ) )
=> (0.4 0.05 0.4465 0)

Result indicates that it took .4 seconds and 0 page faults to build a list from 1 to 10,000 using cons.

myList = nil            ; Initializes the variable myList.
measureTime( for( i 1 1000 myList = append1(myList i) ) )
=> (5.04 0.03 5.06 0)

Result indicates that it took 5 seconds and 0 page faults to build a list from 1 to 1000 using append1.

tab = makeTable("testTable" 'unbound 5000)
=> table:testTable

result = measureTime(for(i 0 10000 tab[i] = t))
=> (0.003 0.0 0.002537012 0)

Related Topics

Core Functions

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