Measuring running time in a general + portable way

On 25 Apr 2007 17:52:27 -0700, upperclass <th********@gmail.comwrote:

>Hi,

I'm trying to find a decent way of measuring the running time of a
long-running program.
Say, the running time ranges from several seconds to more than a day.

The standard clock() function seems inadequate for this task.
(I read somewhere in this group that clock_t would likely overflow
after <1 hour).

Is there any better solution that can deal with this and be portable?
Thank you.

IIANM, difftime will portably give you the difference between two wall
clock times. See time.h. If you have posix (widely available) you can
a finer resolution than seconds.

Apr 26 '07 #2

CBFalconer

Richard Harter wrote:

>
NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500

Your clock is in serious error.

--
<http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.txt>
<http://www.securityfocus.com/columnists/423>
<http://www.aaxnet.com/editor/edit043.html>
cbfalconer at maineline.net

--
Posted via a free Usenet account from http://www.teranews.com

Apr 26 '07 #3

On Thu, 26 Apr 2007 00:25:27 -0400, CBFalconer <cb********@yahoo.com>
wrote:

>Richard Harter wrote:
>>
NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500

Your clock is in serious error.

Huh???

Apr 26 '07 #4

Richard Harter wrote:

On Thu, 26 Apr 2007 00:25:27 -0400, CBFalconer <cb********@yahoo.com>
wrote:

>>Richard Harter wrote:

>> NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500

Your clock is in serious error.

Huh???

date
Thu Apr 26 18:58:54 NZST 2007

Your posting was dated 04/27/07 06:54

--
Ian Collins.

Apr 26 '07 #5

On Thu, 26 Apr 2007 19:01:11 +1200, Ian Collins <ia******@hotmail.com>
wrote:

>Richard Harter wrote:
>On Thu, 26 Apr 2007 00:25:27 -0400, CBFalconer <cb********@yahoo.com>
wrote:

>>>Richard Harter wrote:

NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500

Your clock is in serious error.

Huh???

date
Thu Apr 26 18:58:54 NZST 2007

Your posting was dated 04/27/07 06:54

I am puzzled. The header info is:

Path:
border1.nntp.dca.giganews.com!nntp.giganews.com!lo cal01.nntp.dca.giganews.com!nntp.rapidnet.com!news .rapidnet.com.POSTED!not-for-mail
NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500
From: cr*@tiac.net (Richard Harter)
Newsgroups: comp.lang.c
Subject: Re: Measuring running time in a general + portable way
Date: Thu, 26 Apr 2007 13:22:00 GMT
Message-ID: <46****************@news.sbtc.net>
References: <11**********************@r30g2000prh.googlegroups .com>
X-Newsreader: Forte Free Agent 1.1/32.230
Lines: 21
NNTP-Posting-Host: 208.53.229.199
X-Trace:
sv3-rXZz57965mmdYAuUVuQRD17DWMURcFlXdXbDMUfMXl43d/T9ZXu6mX3LcF/m6gzUkMzDCQCu+XGcizQ!9GakYvoucalohljq5M2o1XqHkbjAC 2SCYvRKqvGjmKFnu/DwLjRCBkrPNmJTaIsnZs6DYQpsDns=
X-Complaints-To: ab***@rapidnet.com
X-DMCA-Complaints-To: ab***@rapidnet.com
X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers
X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your
complaint properly
X-Postfilter: 1.3.34
Xref: number1.nntp.dca.giganews.com comp.lang.c:743832

Where are you getting this 04/27/07 06:54 from?

Apr 26 '07 #6

Richard Heathfield

Richard Harter said:

On Thu, 26 Apr 2007 19:01:11 +1200, Ian Collins <ia******@hotmail.com>
wrote:

>>Richard Harter wrote:
>>On Thu, 26 Apr 2007 00:25:27 -0400, CBFalconer
<cb********@yahoo.comwrote:

Richard Harter wrote:

NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500

Your clock is in serious error.

Huh???

date
Thu Apr 26 18:58:54 NZST 2007

Your posting was dated 04/27/07 06:54

I am puzzled.

Why? Have you never seen people make mistakes before?

--
Richard Heathfield
"Usenet is a strange place" - dmr 29/7/1999
http://www.cpax.org.uk
email: rjh at the above domain, - www.

Apr 26 '07 #7

Richard Harter wrote:

On Thu, 26 Apr 2007 19:01:11 +1200, Ian Collins <ia******@hotmail.com>
wrote:

>>Richard Harter wrote:

>>>On Thu, 26 Apr 2007 00:25:27 -0400, CBFalconer <cb********@yahoo.com>
wrote:
Richard Harter wrote:
NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500

Your clock is in serious error.

Huh???

date
Thu Apr 26 18:58:54 NZST 2007

Your posting was dated 04/27/07 06:54

I am puzzled. The header info is:

Path:
border1.nntp.dca.giganews.com!nntp.giganews.com!lo cal01.nntp.dca.giganews.com!nntp.rapidnet.com!news .rapidnet.com.POSTED!not-for-mail
NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500
From: cr*@tiac.net (Richard Harter)
Newsgroups: comp.lang.c
Subject: Re: Measuring running time in a general + portable way
Date: Thu, 26 Apr 2007 13:22:00 GMT

In my view of the header (and probably Chuck's), Date (as set by your
agent) was 04/27/07 06:54, which usually happens when the sender system
clock is wrong. The NNTP-Posting-Date is set by the server.

Only your postings appear to be in the future.

--
Ian Collins.

Apr 26 '07 #8

On Thu, 26 Apr 2007 20:29:03 +1200, Ian Collins <ia******@hotmail.com>
wrote:

>Richard Harter wrote:
>On Thu, 26 Apr 2007 19:01:11 +1200, Ian Collins <ia******@hotmail.com>
wrote:

>>>Richard Harter wrote:

On Thu, 26 Apr 2007 00:25:27 -0400, CBFalconer <cb********@yahoo.com>
wrote:
>Richard Harter wrote:
>
>
> NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500
>
>Your clock is in serious error.

Huh???
date
Thu Apr 26 18:58:54 NZST 2007

Your posting was dated 04/27/07 06:54

I am puzzled. The header info is:

Path:
border1.nntp.dca.giganews.com!nntp.giganews.com!l ocal01.nntp.dca.giganews.com!nntp.rapidnet.com!new s.rapidnet.com.POSTED!not-for-mail
NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500
From: cr*@tiac.net (Richard Harter)
Newsgroups: comp.lang.c
Subject: Re: Measuring running time in a general + portable way
Date: Thu, 26 Apr 2007 13:22:00 GMT

In my view of the header (and probably Chuck's), Date (as set by your
agent) was 04/27/07 06:54, which usually happens when the sender system
clock is wrong. The NNTP-Posting-Date is set by the server.

Only your postings appear to be in the future.

This is very weird. My clock has the correct time and date. Moreover
the times show up correctly when I download them.

Apr 26 '07 #9

On Thu, 26 Apr 2007 07:42:51 +0000, Richard Heathfield
<rj*@see.sig.invalidwrote:

>Richard Harter said:

>On Thu, 26 Apr 2007 19:01:11 +1200, Ian Collins <ia******@hotmail.com>
wrote:

>>>Richard Harter wrote:
On Thu, 26 Apr 2007 00:25:27 -0400, CBFalconer
<cb********@yahoo.comwrote:

>Richard Harter wrote:
>
> NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500
>
>Your clock is in serious error.

Huh???
date
Thu Apr 26 18:58:54 NZST 2007

Your posting was dated 04/27/07 06:54

I am puzzled.

Why? Have you never seen people make mistakes before?

Ian says he's seeing my posting as coming in the future. Do you see
this also?

Apr 26 '07 #10

Richard Heathfield

Richard Harter said:

Richard Heathfield wrote:
>>Richard Harter said:
>>Ian Collins wrote:

<snip>

>>>>
Your posting was dated 04/27/07 06:54

I am puzzled.

Why? Have you never seen people make mistakes before?

Ian says he's seeing my posting as coming in the future. Do you see
this also?

No. In my view (er, literally!), he is mistaken.

--
Richard Heathfield
"Usenet is a strange place" - dmr 29/7/1999
http://www.cpax.org.uk
email: rjh at the above domain, - www.

Apr 26 '07 #11

Joachim Schmitz

"Richard Harter" <cr*@tiac.netschrieb im Newsbeitrag
news:46****************@news.sbtc.net...

On Thu, 26 Apr 2007 07:42:51 +0000, Richard Heathfield
<rj*@see.sig.invalidwrote:

>>Richard Harter said:

>>On Thu, 26 Apr 2007 19:01:11 +1200, Ian Collins <ia******@hotmail.com>
wrote:

Richard Harter wrote:
On Thu, 26 Apr 2007 00:25:27 -0400, CBFalconer
<cb********@yahoo.comwrote:
>
>>Richard Harter wrote:
>>
>> NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500
>>
>>Your clock is in serious error.
>
Huh???
>

date
Thu Apr 26 18:58:54 NZST 2007

Your posting was dated 04/27/07 06:54

I am puzzled.

Why? Have you never seen people make mistakes before?

Ian says he's seeing my posting as coming in the future. Do you see
this also?

Yes.

Confused am with pm? I see a 12 hours difference

Bye, Jojo

Apr 26 '07 #12

Richard Heathfield wrote:

Richard Harter said:

>>Richard Heathfield wrote:

>>>Richard Harter said:

Ian Collins wrote:

<snip>

>>>>>Your posting was dated 04/27/07 06:54

I am puzzled.

Why? Have you never seen people make mistakes before?

Ian says he's seeing my posting as coming in the future. Do you see
this also?

No. In my view (er, literally!), he is mistaken.

I'm not, something software is!

Richard's postings appear to have a date 24 hours ahead of their
NNTP-Posting-Date.

--
Ian Collins.

Apr 26 '07 #13

Richard Heathfield

Ian Collins said:

Richard Heathfield wrote:

<snip>

>In my view (er, literally!), [Ian Collins] is mistaken.

I'm not, something software is!

Richard [Harter]'s postings appear to have a date 24 hours ahead of
their NNTP-Posting-Date.

Ian, I spoke too soon and I owe you an apology.

Here is an extract from a Richard Harter header - in fact, it's taken
from the same header that he quoted himself in an effort to defend his
system:

NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500
From: cr*@tiac.net (Richard Harter)
Newsgroups: comp.lang.c
Subject: Re: Measuring running time in a general + portable way
Date: Thu, 26 Apr 2007 13:22:00 GMT

The discrepancy between NNTP-Posting-Date and the apparent date is very
evident.

--
Richard Heathfield
"Usenet is a strange place" - dmr 29/7/1999
http://www.cpax.org.uk
email: rjh at the above domain, - www.

Apr 26 '07 #14

CBFalconer

Richard Harter wrote:

On Thu, 26 Apr 2007 20:29:03 +1200, Ian Collins <ia******@hotmail.comwrote:
>Richard Harter wrote:
>>On Thu, 26 Apr 2007 19:01:11 +1200, Ian Collins <ia******@hotmail.comwrote:

These posts show up here, converted to local time, as:

3:01 AM
3:27 PM
4:29 AM
5:16 PM

which smells like a 12 hour displacement in your time setting.

--
<http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.txt>
<http://www.securityfocus.com/columnists/423>
<http://www.aaxnet.com/editor/edit043.html>
cbfalconer at maineline.net

--
Posted via a free Usenet account from http://www.teranews.com

Apr 26 '07 #15

CBFalconer

Richard Harter wrote:

CBFalconer <cb********@yahoo.comwrote:
>Richard Harter wrote:
>>>
NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500

Your clock is in serious error.

Huh???

Apologies. I misread the day.

--
<http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.txt>
<http://www.securityfocus.com/columnists/423>
<http://www.aaxnet.com/editor/edit043.html>
cbfalconer at maineline.net

--
Posted via a free Usenet account from http://www.teranews.com

Apr 26 '07 #16

Flash Gordon

Richard Heathfield wrote, On 26/04/07 11:59:

Ian Collins said:
>Richard Heathfield wrote:

<snip>

>>In my view (er, literally!), [Ian Collins] is mistaken.

I'm not, something software is!

Richard [Harter]'s postings appear to have a date 24 hours ahead of
their NNTP-Posting-Date.

Ian, I spoke too soon and I owe you an apology.

Here is an extract from a Richard Harter header - in fact, it's taken
from the same header that he quoted himself in an effort to defend his
system:

NNTP-Posting-Date: Wed, 25 Apr 2007 20:22:21 -0500
From: cr*@tiac.net (Richard Harter)
Newsgroups: comp.lang.c
Subject: Re: Measuring running time in a general + portable way
Date: Thu, 26 Apr 2007 13:22:00 GMT

The discrepancy between NNTP-Posting-Date and the apparent date is very
evident.

I suggest checking the timezone on the machine, AM/PM and the date. The
Date header says the time is in GMT and I don't think Richard Harter is
in a country using GMT as its timezone.

13:22 - 5:00 gives us 8:00 (I got the -5 from the offset on the posting
date).
An AM/PM error deals with the difference between 8:22 and 20:22.
--
Flash Gordon

Apr 26 '07 #17

On Thu, 26 Apr 2007 06:57:45 -0400, CBFalconer <cb********@yahoo.com>
wrote:

>Richard Harter wrote:
>On Thu, 26 Apr 2007 20:29:03 +1200, Ian Collins <ia******@hotmail.comwrote:
>>Richard Harter wrote:
On Thu, 26 Apr 2007 19:01:11 +1200, Ian Collins <ia******@hotmail.comwrote:

These posts show up here, converted to local time, as:

3:01 AM
3:27 PM
4:29 AM
5:16 PM

which smells like a 12 hour displacement in your time setting.

And so it is. Until I just changed it, it read 10:47 PM. It should be
okay now. Blush, blush.

Thanks muchly, everyone.

Apr 26 '07 #18

measuring disk usage of records

Richard Heathfield wrote:

>
Ian, I spoke too soon and I owe you an apology.

I think I've just found my new sig :)

--
Ian Collins.

Apr 26 '07 #19

Richard Bos

CBFalconer <cb********@yahoo.comwrote:

Richard Harter wrote:
On Thu, 26 Apr 2007 20:29:03 +1200, Ian Collins <ia******@hotmail.comwrote:
Richard Harter wrote:
On Thu, 26 Apr 2007 19:01:11 +1200, Ian Collins <ia******@hotmail.comwrote:

These posts show up here, converted to local time, as:

3:01 AM
3:27 PM
4:29 AM
5:16 PM

which smells like a 12 hour displacement in your time setting.

Another proof that the 24-hour clock is superior to your poncy USAnian
12-hour one...

Richard, g,d,rlb

Apr 27 '07 #20

websnarf

On Apr 25, 5:52 pm, upperclass <thammak...@gmail.comwrote:

I'm trying to find a decent way of measuring the running time of a
long-running program.
Say, the running time ranges from several seconds to more than a day.

The standard clock() function seems inadequate for this task.
(I read somewhere in this group that clock_t would likely overflow
after <1 hour).

Is there any better solution that can deal with this and be portable?

Well not really, but if overflow is your highest priority, then

#include <limits.h>
#include <time.h>

double monotimer (void (*something) (void * p), void * p) {
double dt, cdt;
time_t start = time (NULL), end;
clock_t cstart = clock(), cend;

something (p); /* Whatever you are timing */

dt = difftime (end = time (NULL), start);
cdt = (cend = clock ()) - cstart;
ock must have wrapped around (via difftime()) and simply offset that
to the clock difference (after casting to a large enough type, like
double or
if (dt >= floor (((double) ULONG_MAX) / CLOCKS_PER_SEC)) return
dt;
return cdt / (double) CLOCKS_PER_SEC;
}

So after around 50 days of running time you will switch from cycle
timer to wall clock time on Unix systems. On Windows both just
measure wall clock time in different units. So on Windows you could
do more by trying to calculate how many times the clock wrapped around
(after casting it to a double or an int64_t).

--
Paul Hsieh
http://www.pobox.com/~qed
http://bstring.sf.net/

Apr 27 '07 #21

by: Jonas Kölker | last post by:

Hello. I'm doing a Rubik's Cube timer, so I need a function to measure 100ths of a second. I've browsed through the library reference of python.org, but I didn't find anything that struck me as...

Python

by: Matthew Nuzum | last post by:

We've had a chance to talk to some of our competitors who have recently gone out of business. One of the major failings that contributed to their collapse was not accurately understanding how much...

PostgreSQL Database

Measuring time differences

by: Dominik Wallner | last post by:

Hi! I'm currently implementing a program which measures voltages through an external USB-AD-converter. It should output those values as time/voltage pairs. My problem is to measure the time...

General method for dynamically allocating memory for a string

by: smnoff | last post by:

I have searched the internet for malloc and dynamic malloc; however, I still don't know or readily see what is general way to allocate memory to char * variable that I want to assign the substring...

Isn't it time there was a standard align statement?

by: artifact.one | last post by:

It'd be really pleasant (in my opinion) if the next revision of the C language actually allowed some portable control over data alignment. Compiler-specific mechanisms for this stuff are so...

measuring running time

by: upperclass | last post by:

Hi, I'm trying to find a decent way to measure program running time. I know clock() is probably the standard way of doing it but clock_t overflows too quickly. The target program running time...

Measuring recurring elapsed time

by: Ross | last post by:

I'm a newbie at this, and have searched a lot but can't find something that seems appropriate for measuring a recurring elapsed time. Creating an object with: var mydate = new Date(); seems...

Javascript

How to turn on java script in a villaon keypad mobile phone

by: Charles Arthur | last post by:

How do i turn on java script on a villaon, callus and itel keypad mobile phone

Java

Migrating Website to Cloud - Emmanuel Katto

by: emmanuelkatto | last post by:

Hi All, I am Emmanuel katto from Uganda. I want to ask what challenges you've faced while migrating a website to cloud. Please let me know. Thanks! Emmanuel

General

Looking to do Android software development, any suggestions? Is flutter better?

by: nemocccc | last post by:

hello, everyone, I want to develop a software for my android phone for daily needs, any suggestions?

General

Is that possible of reading the .csv file in column wise and the column have different lengths ?

by: Sonnysonu | last post by:

This is the data of csv file 1 2 3 1 2 3 1 2 3 1 2 3 2 3 2 3 3 the lengths should be different i have to store the data by column-wise with in the specific length. suppose the i have to...

Problem With Comparison Operator <=> in G++

How to build RAID in BIOS?

by: Hystou | last post by:

There are some requirements for setting up RAID: 1. The motherboard and BIOS support RAID configuration. 2. The motherboard has 2 or more available SATA protocol SSD/HDD slots (including MSATA, M.2...

Computer Hardware

by: Oralloy | last post by:

Hello folks, I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>". The problem is that using the GNU compilers,...