How to show only processes not matching a filter

filterhtop

I'm using htop to interactively monitor my processes.

However, sometimes a few processes get "in the way" and I would like to filter them out.

Unfortunately, it seems that htop's built in filter (e.g. F4) only allows me to define a positive filter (only matches will be shown), and not negative filters (all but matches are shown).

Finally, I haven't found any documentation about the actual syntax of the search-string (regexes don't seem to work).

Best Answer

I don't know if it's doable with htop but if using another top implementation is an option, with the top implementation in procps on Linux (generally the default implementation there), from within top, you can

enter o (or O for case sensitive matching)
enter !COMMAND=notwanted (or !USER=unwanted)

to filter out the processes whose name (or command line after pressing c) contains notwanted (or whose username contains unwanted). Enter = to remove all the filters.

You can filter on any of the fields you want, but only when they are displayed. For instance, to exclude kernel tasks, you can ask for the CODE column to be displayed (with f) and then filter on CODE>0 (with o).

Note that the default interface of that top implementation may look cruder than that of htop, but it has actually quite a lot more features (and you can configure it with colour and extra information if need be).

Related Solutions

List files not matching given string in filename

With GNU ls (the version on non-embedded Linux and Cygwin, sometimes also found elsewhere), you can exclude some files when listing a directory.

ls -I 'temp_log.*' -lrt

(note the long form of -I is --ignore='temp_log.*')

With zsh, you can let the shell do the filtering. Pass -d to ls so as to avoid listing the contents of matched directories.

setopt extended_glob          # put this in your .zshrc
ls -dltr ^temp_log.*

With ksh, bash or zsh, you can use the ksh filtering syntax. In zsh, run setopt ksh_glob first. In bash, run shopt -s extglob first.

ls -dltr !(temp_log.*)

How to display only a process and its descendant processes on htop

Under Linux, you can do:

htop -p `pstree -p $PID | perl -ne 'push @t, /\((\d+)\)/g; END { print join ",", @t }'`

where $PID is the root process. This works as follows:

The list of the wanted processes are obtained with pstree, using the -p option to list them with their PID.
The output is piped to a Perl script that retrieves the PID's, using a regular expression (here, $(\d+)$), and outputs them separated with commas.
This list is provided as an argument of htop -p.

For other OS like Mac OS, you may need to adapt the regular expression that retrieves the PIDs.

Note: It is unfortunately not possible to update the list with new children that are spawn later, because once htop has been executed, one cannot do anything else. This is a limitation of htop (current version: 2.0.2).

Best Answer

Related Solutions

List files not matching given string in filename

How to display only a process and its descendant processes on htop

Related Question