dispatch_benchmark(3) BSD Library Functions Manual dispatch_benchmark(3)NAME
dispatch_benchmark -- Measures block execution time
SYNOPSIS
#include <dispatch/dispatch.h>
uint64_t
dispatch_benchmark(size_t count, void (^block)(void));
uint64_t
dispatch_benchmark_f(size_t count, void *context, void (*function)(void *));
DESCRIPTION
The dispatch_benchmark() function executes the given block multiple times according to the count variable and then returns the average number
of nanoseconds per execution. This function is for debugging and performance analysis work. For the best results, pass a high count value
to dispatch_benchmark(). When benchmarking concurrent code, please compare the serial version of the code against the concurrent version,
and compare the concurrent version on different classes of hardware. Please look for inflection points with various data sets and keep the
following facts in mind:
o Code bound by computational bandwidth may be inferred by proportional changes in performance as concurrency is increased.
o Code bound by memory bandwidth may be inferred by negligible changes in performance as concurrency is increased.
o Code bound by critical sections may be inferred by retrograde changes in performance as concurrency is increased.
o Intentional: locks, mutexes, and condition variables.
o Accidental: unrelated and frequently modified data on the same cache-line.
RETURN VALUE
The dispatch_benchmark() function returns the average number of nanoseconds the given block takes to execute.
SEE ALSO dispatch(3)Darwin May 1, 2009 Darwin
I try to read in a file and write out a new file with increased number at the end of each line. And I can set the initial value and increased constant from inputs.
input file:
text1
text2
text3
...
text100
if I set initial value is 10, and increased constant is 0.4
output file:
text1... (3 Replies)
the count is off ... man ... help please.
The Code
open (FILE1, "xy1.TXT") or die "$0: Could not open SOURCEFILE.TXT: $!\n";
open (FILE2, "xy2.TXT") or die "$0: Could not open RESULTFILE.TXT: $!\n";
chomp(my @strings = <FILE2>);
while (1) {
foreach $pattern (<FILE1>) {
... (3 Replies)
Hi Friends,
Can any one help me with count average of student marks in this file (i can not change structure of the input file):
input file:
1:John Smith:2 3 4 5
2:Mark Anderson:3 2
3:Susan Waterman:2 4 2
(numbers of marks are different)
output:
Name:John Smith
ID#: 1
Avg. mark:... (6 Replies)
Hello,
Does anyone have a good link which outlines symptoms for different performance issues related to IO? I am looking for data I can compare to my IOSTAT or VMSTAT output. For example, I am trying to see if my disk is thrashing..does anyone have output on vmstat or iostat from when there disk... (3 Replies)
count=0;
while read line;
do ] && let count=count+1; done < file_name.txt
echo
echo "$count of 10 files found "
echo
The scenario is a follows :
I have a file which contains a list of filenames present in particular directory .
I am checking fo the existence of the file and... (5 Replies)
Hi
I have a file which contains count for a code. Code is first field and count is second field.
I am trying to search the code and get correspond count.
File look like this. temp.out
A 10
B 20
I am searching for C , if C is not there I will have get value 0.
I have... (5 Replies)
Is/Are there an/some application/applications , package/packages for benchmarking or system performance measuring which are there for almost all Linux releases and distributions? (2 Replies)
Hi,
I have the following text in a file:
ISA*00* *00* *ZZ*ENS_EDI *ZZ*GATE0215 *110106*2244*U*00401*006224402*1*P*>~
GS*HP*ENS_EDI*GATE0215*20110106*2244*6224402*X*004010X091A1~
ST*835*00006~... (2 Replies)
#!/bin/bash
count=1
while read line
do
if (($count > 4)); then
awk -v var1="$count" '{printf "%3s%8s%11s%11s%11s\n",var1,$2,$3,$4,$5}'
else
echo $line
fi
count=$((count+1))
done < posre_sub.itp > test
cat test
INPUT:
; position restraints for... (3 Replies)
Dear Guru,
IHAC who complaint that his CentOS is getting performance issue.
I have to help him out of there.
Could you please tell me which tools is better to gathering the whole system performance data?
-- CPU/Memory/IO(disk & Network)/swap
I would like the tools could be... (6 Replies)
Hi,
What are the differences between concurrent and enhanced concurrent VGs.?
Any advantages of enhanced concurrent VG over normal concurrent vg
Regards,
Siva (2 Replies)
Hi All,
I have a requirement to make a oracle concurrent program end with
warning based on a given condition. If the condition is true, the
concurrent program should end with completed warning status.
The host program I am using is a shell script that checks if a file exists.
... (2 Replies)
Hi Guys,
I need to determine the employee performance and calculate their salaries based on each quarter
Expected output
enter the no. of Employee 2
2
Enter Employee Name sam
Enter salary 1000
Enter Q1 5
Enter Q2 6
Enter Q3 3
Enter Q4 5
Enter Employee Name anderson
Enter salary... (17 Replies)