Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: Which cut command is more efficient?
Top Forums UNIX for Advanced & Expert Users Which cut command is more efficient? Post 302508570 by Corona688 on Monday 28th of March 2011 01:08:51 PM
Old 03-28-2011
Quote:
Originally Posted by methyl
My stats do not show waste of CPU power. They show a CPU power saving by using "cat" because "cut" is less efficient at reading files.
So reading the file, writing it to a pipe, and reading from the pipe, utilizing two separate CPU's simultaneously is more efficient than reading it once and using it once? If your CPU benchmarks show that this uses less CPU, frankly, they're wrong. Less total real time maybe, but nothing in that reduces the amount of CPU cut uses -- adding more commands can only add more CPU utilization.

The only performance benefit I can see is the pipe effectively acts as a read-ahead buffer, albeit a highly expensive one. With the power expended for that 1% performance improvement, how much more actual work could have been done instead by running two instances of cut on different data sets?

---------- Post updated at 11:08 AM ---------- Previous update was at 10:58 AM ----------

Quote:
Originally Posted by shamrock
What makes you arrive at the fact that..."cut" is less efficient at reading files than cat.
cut has to read line by line. cat can just read and write huge blocks.
Last edited by Corona688; 03-28-2011 at 02:14 PM..
 

9 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

cut command

how do you show just the used disk space. using the cut and df command?? or does anyone have any other suggestions on how to do it a better way? (3 Replies)
Discussion started by: rookie22
3 Replies

2. Shell Programming and Scripting

Cut command

Hi, I want to cut from a particular position to a particular position and retain the rest. I tried this cut -c31-51 file1.txt > file2.txt But The characters from the position 31 to 51 were only present in file2.txt. Is there a way to reverse this i.e to retain the rest except from... (1 Reply)
Discussion started by: ragavhere
1 Replies

3. Shell Programming and Scripting

Help with cut command

Gurus, I need help with the cut command : I have a file with garbage charaters at the beginning of each record; but these characters are not of the same length; First record has 3 garbage chars to be removed; rest have 2; If the length was consistent across all the records, I could have... (3 Replies)
Discussion started by: tru_tell
3 Replies

4. Shell Programming and Scripting

Cut Command error cut: Bad range

Hi Can anyone what I am doing wrong while using cut command. for f in *.log do logfilename=$f Log "Log file Name: $logfilename" logfile1=`basename $logfilename .log` flength=${#logfile1} Log "file length $flength" from_length=$(($flength - 15)) Log "from... (2 Replies)
Discussion started by: dgmm
2 Replies

5. UNIX for Dummies Questions & Answers

Cut pid from ps using cut command

hay i am trying to get JUST the PID from the ps command. my command line is: ps -ef | grep "mintty" | cut -d' ' -f2 but i get an empty line. i assume that the delimiter is not just one space character, but can't figure out what should i do in order to do that. i know i can use awk or cut... (8 Replies)
Discussion started by: ran ber
8 Replies

6. Shell Programming and Scripting

Cut command

hi, i have a file abc,"an,ab",cde,efg abc,anab,cde,efg and need to cut the second field so the output should be abc,cde,efg and i have used cut -d',' -f1-1,3- but its giving me abc,ab",cde,efg abc,cde,efg (4 Replies)
Discussion started by: ATWC
4 Replies

7. UNIX for Beginners Questions & Answers

Cut command: can't make it cut fields

I'm a complete beginner in UNIX (and not a computer science student either), just undergoing a tutoring course. Trying to replicate the instructions on my own I directed output of the ls listing command (lists all files of my home directory ) to My_dir.tsv file (see the screenshot) to make use of... (9 Replies)
Discussion started by: scrutinizerix
9 Replies

8. Shell Programming and Scripting

Combining awk command to make it more efficient

VARIABLE="jhovan 5259 5241 0 20:11 ? 00:00:00 /proc/self/exe --type=gpu-process --channel=5182.0.1597089149 --supports-dual-gpus=false --gpu-driver-bug-workarounds=2,45,57 --disable-accelerated-video-decode --gpu-vendor-id=0x80ee --gpu-device-id=0xbeef --gpu-driver-vendor... (3 Replies)
Discussion started by: SkySmart
3 Replies

9. Shell Programming and Scripting

Efficient way to combine command

im currently running the following command to grab all arguments in front of a script, directly from the process table. # cat /tmp/allmyprocs ubuntu 9933 27793 0 03:29 pts/0 00:00:00 /bin/sh ./prying.sh ubuntu 9941 9933 0 03:29 pts/0 00:00:00 sh ubuntu 9952 9941 0 03:29... (1 Reply)
Discussion started by: SkySmart
1 Replies

LEARN ABOUT SUSE

wmsmpmon

WMSMPMON(1)						      General Commands Manual						       WMSMPMON(1)

NAME

       wmSMPmon - Window Maker System Monitor

SYNOPSIS

       wmSMPmon [options]

DESCRIPTION

       wmSMPmon is a Window Maker dock application that displays the following information about the system:

       - Current CPU utilization of up to two CPUs

       - Up to two minutes history of CPU utilization

       - Current memory usage

       - Current swap usage

       On dual CPU systems, wmSMPmon has three different styles for the utilization graph. To toggle between them just click into the graph.

OPTIONS

       All options start with one dash.

       -h     Show summary of options.

       -r REFRESH_RATE
	      Set the refresh rate of the graph in microseconds. The default is 250000 (a quarter of a second).

       -g GRAPH_STYLE
	      Start  using  graph style #[1-3] (only on dual CPU systems). Style 1 shows the utiliziation in one graph, while 2 and 3 are split in
	      two little graphs. Style 2 shows the two graphs on top of each other. Style 3 uses a mirror like type. The default style is 1, which
	      is also the style used on single CPU systems.

       -c1 IDX, -c2 IDX
	      On  systems  with more than 2 CPUs, select the CPUs to show. Per default CPU number 1 and 2 are shown. On a quad CPU systems you may
	      launch second wmSMPmon showing CPUs number 3 and 4.

       -no-swap
	      Do not monitor swap.

SEE ALSO

       wmaker(1x)

AUTHOR

       This manual  page  was  originally  written  by	Alain  Schroeder  <alain@debian.org>  and  adapted  for  wmSMPmon  3  by  Thomas  Ribbrock
       <emgaron@gmx.net>

																       WMSMPMON(1)
All times are GMT -4. The time now is 11:44 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy