nohang(1)

1nohang(1)                   General Commands Manual                  nohang(1)
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NAME

6       nohang - A highly configurable OOM preventer
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SYNOPSIS

10       nohang [OPTION]...
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DESCRIPTION

14       Nohang  is a highly configurable daemon for Linux which is able to cor‐
15       rectly prevent out of memory (OOM) and keep  system  responsiveness  in
16       low memory conditions.
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REQUIREMENTS

20       For basic usage:
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22           - Linux 3.14+ (since MemAvailable appeared in /proc/meminfo)
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24           - Python 3.3+ (not tested with previous)
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26       To show GUI notifications:
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28           -  Notification  server (most of desktop environments use their own
29       implementations)
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31           -  libnotify  (Fedora,  Arch  Linux)   or   libnotify-bin   (Debian
32       GNU/Linux, Ubuntu)
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34           - sudo if nohang started with UID=0
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36       To use PSI:
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38           - Linux 4.20+
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OPTIONS

42         -h, --help            show this help message and exit
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44         -v, --version         print version
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46         -p, --print-proc-table
47                               print  table  of  processes  with their badness
48       values
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50         -c CONFIG, --config CONFIG
51                               path to the config file, default values:
52                               ./nohang.conf, /etc/nohang/nohang.conf
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54         -cc CONFIG, --check-config CONFIG
55                               check and print config
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HOW TO CONFIGURE

59       The program can be configured by editing the config file.
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61       The configuration includes the following sections:
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63           - Memory levels to respond to as an OOM threat
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65           - Response on PSI memory metrics
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67           - The frequency of checking the level of available memory (and  CPU
68       usage)
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70           - The prevention of killing innocent victims
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72           - Impact on the badness of processes via matching their names, cmd‐
73       lines and UIDs with regular expressions
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75           - The execution of a specific command or sending any signal instead
76       of sending the SIGTERM signal
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78           - GUI notifications:
79               - notifications of corrective actions taken
80               - low memory warnings
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82           - Verbosity
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84           - Misc
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86       Just read the description of the parameters and edit the values.
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88       Please restart nohang to apply the changes.
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90       Default path to the config after installing is /etc/nohang/nohang.conf.
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LOGGING

94       To view the latest entries in the log (for systemd users):
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96       $ sudo journalctl -eu nohang
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98       See also man journalctl.
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100       You   can  also  enable  separate_log  in  the  config  to  logging  in
101       /var/log/nohang/nohang.log.
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