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Operating Systems Linux Underutilization of Linux memory Post 303044176 by Neo on Sunday 16th of February 2020 07:13:01 AM
Old 02-16-2020
To further illustrate this point, I have a Linux (Ubuntu) server running (in VM mode) only MQTT services and Node-RED (for the most part), and I just did this on a real, live server in production:

Code:
root@localhost:~# swapoff -a

I am also graphing the performance, which currently looks like this:

Underutilization of Linux memory-screen-shot-2020-02-16-71101-pmjpg


I will post the same graph in one day to compare.

Then, after that, I will do the same for an even busier Linux server (Ubuntu, dedicated server, running many web services and sites, MQTT, backups, and more)..... to illustrate.

After turning off swap on this system:

Code:
Tasks:  93 total,   1 running,  52 sleeping,   0 stopped,   0 zombie
%Cpu(s):  0.3 us,  0.7 sy,  0.0 ni, 99.0 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
KiB Mem :  2041224 total,   229536 free,   403428 used,  1408260 buff/cache
KiB Swap:        0 total,        0 free,        0 used.  1457936 avail Mem 

  PID USER      PR  NI    VIRT    RES    SHR S %CPU %MEM     TIME+ COMMAND                                                                                                            
25673 mosquit+  10 -10   48028   5708   5044 S  0.3  0.3  19:05.65 mosquitto                                                                                                          
29531 node-red   5 -15 1364496 177400  23296 S  0.3  8.7  66:17.99 node-red                                                                                                           
    1 root      20   0  225412   9208   6704 S  0.0  0.5   2:34.75 systemd   

....
...
...

24 hours from now I will post the graphs and update on this VM Ubuntu instance.

Nothing but the facts .... no guesses, no opinions, and no personal preferences in this test. Just "turn off swap" and show the results at the same time, a day later.

Code:
ubuntu_vm# uptime
 13:15:58 up 116 days, 11:56,  1 user,  load average: 0.00, 0.00, 0.00

 

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Locale::Codes::LangVar(3pm)				 Perl Programmers Reference Guide			       Locale::Codes::LangVar(3pm)

NAME
Locale::Codes::LangVar - standard codes for language variation identification SYNOPSIS
use Locale::Codes::LangVar; $lvar = code2langvar('acm'); # $lvar gets 'Mesopotamian Arabic' $code = langvar2code('Mesopotamian Arabic'); # $code gets 'acm' @codes = all_langvar_codes(); @names = all_langvar_names(); DESCRIPTION
The "Locale::Codes::LangVar" module provides access to standard codes used for identifying language variations, such as those as defined in the IANA language registry. Most of the routines take an optional additional argument which specifies the code set to use. If not specified, the default IANA language registry codes will be used. SUPPORTED CODE SETS
There are several different code sets you can use for identifying language variations. A code set may be specified using either a name, or a constant that is automatically exported by this module. For example, the two are equivalent: $lvar = code2langvar('en','alpha-2'); $lvar = code2langvar('en',LOCALE_CODE_ALPHA_2); The codesets currently supported are: alpha This is the set of alphanumeric codes from the IANA language registry, such as 'arevela' for Eastern Armenian. This code set is identified with the symbol "LOCALE_LANGVAR_ALPHA". This is the default code set. ROUTINES
code2langvar ( CODE [,CODESET] ) langvar2code ( NAME [,CODESET] ) langvar_code2code ( CODE ,CODESET ,CODESET2 ) all_langvar_codes ( [CODESET] ) all_langvar_names ( [CODESET] ) Locale::Codes::LangVar::rename_langvar ( CODE ,NEW_NAME [,CODESET] ) Locale::Codes::LangVar::add_langvar ( CODE ,NAME [,CODESET] ) Locale::Codes::LangVar::delete_langvar ( CODE [,CODESET] ) Locale::Codes::LangVar::add_langvar_alias ( NAME ,NEW_NAME ) Locale::Codes::LangVar::delete_langvar_alias ( NAME ) Locale::Codes::LangVar::rename_langvar_code ( CODE ,NEW_CODE [,CODESET] ) Locale::Codes::LangVar::add_langvar_code_alias ( CODE ,NEW_CODE [,CODESET] ) Locale::Codes::LangVar::delete_langvar_code_alias ( CODE [,CODESET] ) These routines are all documented in the Locale::Codes::API man page. SEE ALSO
Locale::Codes The Locale-Codes distribution. Locale::Codes::API The list of functions supported by this module. http://www.iana.org/assignments/language-subtag-registry The IANA language subtag registry. AUTHOR
See Locale::Codes for full author history. Currently maintained by Sullivan Beck (sbeck@cpan.org). COPYRIGHT
Copyright (c) 2011-2012 Sullivan Beck This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. perl v5.16.2 2012-10-11 Locale::Codes::LangVar(3pm)
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