Questions tagged [time]
`time` is a command line utility for running another program and summarizing resource usage
467
questions
5
votes
4
answers
673
views
How can I make time measurement DRY in my bash scripts?
Based on this answer, to measure the time in my bash scripts I can use:
start_time="$(date -u +%s.%N)"
sleep 5
end_time="$(date -u +%s.%N)"
elapsed="$(bc <<<"$...
- 415
0
votes
3
answers
61
views
Read and convert date from file
I'm using a CentOS and I want to write a shell script. So
I have a file with a date:
>
> cat VM1_EOMAP_TIME.log
07 Sep 2022 16:30
>
And I want to get the minutes since current time and the ...
3
votes
1
answer
208
views
Is the kilobyte used by time and ulimit commands either 1000 (SI) or 1024 (old school) bytes?
From man time:
M Maximum resident set size of the process during its lifetime, in Kilobytes.
From ulimit -a:
max memory size (kbytes, -m) unlimited
But a "kilobyte" may mean ...
- 165
0
votes
0
answers
23
views
linuxptp PHC with delay > 10us
I am using linuxptp package to sync between my 2 linux machines both have same configuration
Linux 5.10.0-14-rt-amd64 #1 SMP PREEMPT_RT Debian 5.10.113-1 (2022-04-29) x86_64 GNU/Linux.
I am getting a ...
- 1
5
votes
0
answers
127
views
tee is faster than no tee
I have this simple bash script
#!/bin/sh
for i in {1..1000000}
do
echo "hello ${i}"
done
That prints a message a million times
I try to compare the performance of dumping all the ...
- 151
1
vote
0
answers
78
views
Multiple Scripts all in one with breaks [closed]
I’m writing a script where instead of using ‘sleep 600’ (for example), i actually want to execute another script for the same amount of time as sleep.
So basically, instead of “doing nothing” for 10 ...
- 11
19
votes
3
answers
2k
views
What's the POSIX-compliant way to get the epoch timestamp in a shell?
I just noticed, that POSIX date doesn't seem to have the %s or %N format items. So I can't use those. What's an alternative, yet POSIX-compliant way to get the epoch timestamp in my shell script?
- 2,046
1
vote
0
answers
22
views
Counter-intuitive date command [duplicate]
I've been using date in a script in order to add one year to a specific date the following way:
date '+%Y-%m-%d %H:%M:%S' -d "$DATE + 1 year"
In this example, DATE looks like 2022-05-11 14:...
- 11
0
votes
1
answer
116
views
How to store inner output of a nested bash command (within parenthesis) into one file and outer output into another file?
Here's my command:
(time ( \
time sleep 1; \
time sleep 2 \
) 2>&1 | tee inner.txt ) 2>&1 | tee outer.txt
cat inner.txt shows:
real 0m1.003s
user 0m0.001s
sys 0m0.002s
real ...
- 1,578
2
votes
1
answer
256
views
How to pass optional arguments to `time` command [duplicate]
man time shows it has some options, like this, to write just the time output to a file instead of to stderr:
-o FILE, --output=FILE
So, I try to use it
$ time -o out.txt ls
-o: command not found
...
- 1,578
0
votes
2
answers
140
views
Unix Time Format with decimals
According to my understanding, Unix time format is the no of seconds calculated from 1970 00:00:00. For ex, if our current time is 1970 00:01:00, then unix time will be 60 (60 seconds has elapsed from ...
- 3
-1
votes
1
answer
277
views
Why is `time` not working on basic Bash script?
echo -e '#!/bin/bash\nsleep 10' > time_test.sh && chmod +x time_test.sh && time time_test.sh
time_test.sh: No such file or directory
real 0m0.186s
user 0m0.105s
sys 0m0....
- 352
0
votes
1
answer
72
views
Bash time converter
I have a question, How can I convert time from 12h AM/PM format to 24h?
For example, I have input from stdin, some text like this:
The event starts at 03:25PM and is expected to end at 06:17PM.
...
2
votes
2
answers
39
views
Show variable's value in output of time command in zsh
I want to measure runtime of my program for a series on input variables (I am using zsh):
for i in {1..3} ; do time sleep $i ; done
The output is
sleep $i 0,00s user 0,00s system 0% cpu 1,003 total
...
- 123
1
vote
1
answer
799
views
How to disable DST changes for a timezone?
My system timezone is Asia/Tehran, and it has DST changes adjusts in Summer (spring forward) and fall back in Winter; however I do need to disable these DST adjustments and keep timezone always in UTC+...
- 38.9k
3
votes
1
answer
358
views
Check status of 11-Minute Kernel mode using adjtimex
I have a Debian Buster system which has the Kernel compiled without the CONFIG_RTC_SYSTOHC since I DO NOT want the 11-minute kernel mode to be on. However, I wanted to check if this change actually ...
- 75
0
votes
0
answers
21
views
Syncing Debian ntpd with Windows time server [duplicate]
unfortunately my problem listed here was not solved. It would seem that the issue was not with the ntpdate at all: when bypassing the university network all together, time sync works correctly.
The ...
- 43
1
vote
1
answer
189
views
Convert string time to seconds
I'm receiving an uptime in this format:
167h58m10.586582048s
I want to transform it to seconds and discard the fraction part.
I know awk could do that if only the received string had the same ...
- 101
0
votes
2
answers
59
views
Does the time command include the memory claimed by forked processes?
I want to benchmark some scripts with the time command. I am wondering if this command catches child processes' memory usage.
command time -f '%M' python my_script.py
If not, what are my options? Is ...
- 1,325
2
votes
1
answer
705
views
Automatic time synchronization: `ntpdate` works but `chrony` does not
I have a problem with time synchronization of my Linux server. Both this machine and the NTP server are located in a (smaller) university data center hence the local address.
What is strange is that ...
- 43
0
votes
1
answer
153
views
Show only dates bigger than the search pattern even if the search pattern does not exist in the (log) file
I want to search the syslog for dates bigger than a specific search pattern. For example I want to find every syslog entry where the date is bigger than JAN 6 16:24:00. I know I could use sed (sed -n ...
- 2,333
0
votes
2
answers
319
views
Wrong Local time Archlinux + Xfce4
My system local clock has been displayed incorrectly for several days. when i run timedatectl status output is something like this :
➜ timedatectl status
Local time: Sat 2021-12-25 19:16:57 +0330
...
- 101
0
votes
1
answer
82
views
Duration of host unreachable by ping
Suppose I am pinging an IP and the destination is reachable. I did some change in the network so for a few seconds the destination was unreachable. After few seconds it comes live again.
Is there any ...
0
votes
0
answers
62
views
How to measure CPU, MEM usage and more for a short lived process
I've got a program with some compiled sorting algorithms, and I'm trying to use top to monitor its cpu and ram usage.
Normally this would be fine, given that the process runs for a few minutes, ...
0
votes
0
answers
101
views
Extremely slow booting time in Linux Lite since yesterday (Over 5 minutes), what should I do?
Here are the details:
systemd-analyze
Startup finished in 6.345s (kernel) + 5min 17.341s (userspace) = 5min23.687s
graphical.target reached after 5min 17.322s in userspace
here's what I get with: ...
- 1
0
votes
1
answer
315
views
settimeofday function can't change time
In Ubuntu 20.04 LTS, I write a program using C to change the system time. During the execution of the program, it does output the modified time using commands date and hwclock. But when the program ...
0
votes
0
answers
56
views
PHC2Sys and syscalls with intel NIC have insane high latency
I'm currently working on a device wich is set to give out multiple different timing Protocolls from one PTP-grandmaster. For this i have an RockPro64 SOC with an Intel i350 NIC.
For the Project I ...
- 1
1
vote
0
answers
94
views
Where, besides ntp.conf, do NTP servers used by ntpd come from?
The only NTP servers I have defined in /etc/ntp.conf are as follows:
pool 0.debian.pool.ntp.org iburst
pool 1.debian.pool.ntp.org iburst
pool 2.debian.pool.ntp.org iburst
pool 3.debian.pool.ntp.org ...
- 111
0
votes
1
answer
516
views
Who sets date/time automatically from the hardware clock at boot?
When Linux is booting, the current time must be fetched from a RTC chip and then set to Linux system date/time. I can do this manually by running hwclock --hctosys. But where exactly does this happen ...
- 141
1
vote
3
answers
296
views
When date and timedatectl?
About reporting and settings for date and time exists available the date and timedatectl commands - it according with the most common results available through the web. Practically both do the same.
...
- 1,046
0
votes
0
answers
26
views
PHP - get datetime when jpg file at URL has been accessed last time
I know the date-time is saved in the access log, but I think its not possible to read this file from php.
What is the easiest way to find out the date and time when a specific file (jpg) has been last ...
- 1
0
votes
1
answer
60
views
Fixing problem with %(%H)T giving 12 hour
I am passing a time interval (in seconds) in ts.
ts=13
printf -v hours '%(%H)T' "$ts"
printf '%s\n' "ts: $ts ; hours: $hours"
This is the incorrect result.
ts: 13 ; hours: 12
As ...
- 21
0
votes
1
answer
73
views
How to stop rsyslog output TIMESTAMP
this same question has already received a solution but it doesn't work
I'm looking for exactly this, I apply it in my rsyslog but it doesn't work for me, I restart my rsyslog, and nothing, I restart ...
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0
votes
1
answer
133
views
CentOS 7 changes my pc time +4 hours when I boot my windows disk
On my home pc I have two disks, one disk has windows10 installed, the other disk has CentOS 7.9 installed.
It is an Asrock motherboard and has a boot gui that lets me choose which disk to boot, and I ...
- 4,512
0
votes
1
answer
130
views
Get date when the process was started in epoch seconds
I need to get the date when a particular process was started by PID.
For this purpose, I use:
stat -c %y /proc/PID
In the output, I get the date in the following format:
2021-07-04 11:00:20.352976946 ...
- 111
0
votes
1
answer
144
views
embedded Linux: date of system after boot: which file (it's date exaclty) is responsible
Do have an embedded linux device.It has a r/o rootfs. It has no connection to ethernet to get a time from some server. I am used that such a device comes up with date: 1.1.1970.
Here it is different. ...
- 105
4
votes
4
answers
704
views
Calculate the logon duration of a user in minutes from a file
I have a file on a Linux system that looks like the following:
May 6 19:12:03 sys-login: user1 172.16.2.102 Login /data/netlogon 13473
May 6 19:15:26 sys-login: user2 172.16.2.107 Login /data/netlogon ...
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11
votes
2
answers
891
views
Command 'time' works on its own but not in a pipeline
Consider the following:
# time sleep 1
real 0m1.001s
user 0m0.001s
sys 0m0.000s
# echo foo | time sleep 1
bash: time: command not found
Um... wut?
OK, so clearly Bash is searching for ...
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0
votes
1
answer
223
views
Copying a same file multiple times
I have an audio file, and I am running a script to decode that audio file. Now I want to measure the latency of the system.
So, I am running a script with a time command.
like $ time ./uber.sh
In the ...
- 125
1
vote
0
answers
27
views
Application for tracking applications usage times
Does there exist a program which allows to automatically track "window focus" time in, for example, Gnome? For example, I would like to track how much time per day I spend using a certain ...
- 251
0
votes
2
answers
205
views
How to generate the last 1 hour in seconds in unixtime?
I'm wondering if there is a way of generating the unixtime seconds for the past hour. So 3600 timestamps. Is there a quick date command?
4
votes
3
answers
304
views
command-line tool for converting/formatting time
Is there a command-line tool to convert/format time? (I mean time, not date!)
Here is what I was expecting:
$ timeconverter --format '%s' 1h
3600
$ timeconverter --format '%h:%m:%s' 3665s
1:01:05
$ ...
- 417
-1
votes
3
answers
163
views
How often is unix time divisible by 10,000,000 seconds at midnight?
I accidentally discovered that May 3 2021 was one of the landmarks of Unix time. Exactly at midnight (UTC) the number of time_t was divisible by 10,000,000:
$ date --utc --date='@1620000000'
Mon 3 ...
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0
votes
3
answers
1k
views
What does the SECONDS variable actually do?
So, as the title suggest, I noticed this weird thing where sleep essentially increment the time you give it as argument. Example:
#!/usr/bin/env bash
set -x
SECONDS="1"
while true; do
...
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0
votes
0
answers
14
views
time --format e command fails to recognize format arg?
Can someone please show me how to use time -f "%e" correctly? I want just the real wall clock time in seconds.
- 443
0
votes
1
answer
85
views
Bash-Script: stop/abord if is last Sunday in March or October?
How can I stop/abort a bash-script when:
is last Sunday in March?
OR
is last Sunday in October?
Both should be checked here and if so the bash script should be stopped/aborted.
Thanks in advance.
...
Omexlu
2
votes
1
answer
441
views
command 'top' and 'ps' take a long time to show result
Recently, I find when I run commands like top or ps -aux on a server, it is very slow to show the result (STDOUT). I have checked the usage of disk space, memory, and CPU, all of them are OK.
After ...
- 21
4
votes
1
answer
206
views
Why this 'useless use of cat' with `detex` is 10x faster than the alternative?
I'm counting words in LaTeX files and intuitively used the command:
$ cat *tex | detex | wc -w
I then immediately noticed he useless use of cat, and did the task again with:
$ detex *tex | wc -w
...
- 213
2
votes
0
answers
44
views
Making the locale time format more compact
dmesg -T gives human readable time format, and I want to make it more compact, from this
[Пт мар 12 09:18:54 2021] wlan0: associated
to this
[12.03.21 09:18:54] wlan0: associated
I'm using ru_RU.UTF-...
- 21
0
votes
0
answers
22
views
RHEL ways to simulate or virtualize time
I am trying to get my machine to simulate or visualize time without changing system time so that I can run code under simulated/virtual time so that my timestamps are in the past and such.
I know ...
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