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Htop explained

peteris.rocks

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Re: Htop explained

#91

Post by stevekemp »

ThatGeoGuy wrote: post #46
pjc50 wrote: post #33

Earlier quoted context omitted.

Dependencies in debian systems which rely on "virtual" functionality can often have surprising results. At a guess removing cron removes things which depend on it - perhaps one of those is Exim. Something else "requires" an MTA, so it installs postfix instead to fill the gap.

This would be apt. Apt requires an MTA because maintainer messages / change-lists are sent as mail to the root user.

Close. It is cron that requires a package which provides `mail-transport-agent`, because output from cronjobs is traditionally emailed to users.

You can see this via:

      apt-cache show cron|grep -i mail
Note that the `apt` package itself does not require a MTA.

Re: Htop explained

#92

Post by Watabou »

SkyMarshal wrote: post #61
oschrenk wrote: post #57

Earlier quoted context omitted.

Re 2) I'm running a multi user homebrew setup for years. I have my users (personal and various work accounts) live under the "Local" Group and do ``` sudo chmod -R 770 /usr/local/ sudo chmod -R +a "group:Local allow delete,readattr,writeattr,readextattr,writeextattr,list,search,add_file,add_subdirectory,delete_child,file_inherit,directory_inherit" /usr/local/ ``` I remember sometimes running into permissions issues b…

It's a bit of a smell that Homebrew doesn't do this itself.

Why is 'sudo' required? Just curious.

I moved away from homebrew, to compiling my own software on macOS which I just put in ~/build. I don't use sudo make install since I own the ~/build folder.

What am I doing wrong in this case?

Re: Htop explained

#93

Post by jpitz »

sambe wrote: post #84
guessmyname wrote: post #9

I switched to macOS from Linux two weeks ago and I am starting to regret that decision. Most — if not all — the commands that I thought I had mastered after years working on Linux environments stopped working because their BSD counterparts have slightly differences that completely break everything I try to do. It is even more frustrating when I realize that I have to deactivate security features built-in the new Appl…

You normally do not have to disable security features to run programming/debugging tools, contrary to most of the advice you'll see in forums (and sometimes even Stack Exchange). I haven't used dtrace but non-bundled debuggers were a bit of a pain. You can self-sign these using the procedure described by a quick Google.

Normally, no, but if you want to dtruss uptime, or any other bog standard system utility, then, yes you do.

Re: Htop explained

#94

Post by _TylerDurden_ »

willsher wrote: post #37
p8donald wrote: post #21

Earlier quoted context omitted.

I am getting feedback that I should not be using the terms CPU usage and utilization when talking about load averages. I will update the post later.

My understanding from my Solaris days was that CPU load is the number of processes queued for CPU time over the given period. It doesn't related to usage directly at all. (Other than higher cpu speed and io through out leads to a reduction in load because tasks finish quicker)

That's correct.

Re: Htop explained

#95

Post by digi_owl »

xp3ll3d wrote: post #87
digi_owl wrote: post #5

Earlier quoted context omitted.

unless by non-Linux you meant non-unix, htop recently got updated to better support BSDs and OSX/MacOS.

It can also me installed and run on the new "Ubuntu bash for Windows 10" from Microsoft, which uses the new "Windows subsystem for Linux"

How much of /proc there is filled with dummy data though?

Re: Htop explained

#96

Post by 234dd57d2c8db »

If you have python available, I find `glances` to be a great tool (`pip install glances`)

Has disk, network, proc, mem, cpu, etc. all wrapped up in a a curses interface. very slick and useful.

Re: Htop explained

#97

Post by vram22 »

lsof (LiSt Open Files), which used to be a third-party tool and needed to be install on Unixes, may be built-in by now in some, and fuser (built-in, usually) are also useful tools for investigating processes and files that they open (including sockets), and so on. lsof was written by someone at HP, IIRC. Has a big list of command-line options. Possibly some of the other tools mentioned in this thread call lsof internally.

Re: Htop explained

#98

Post by renaudg »

shmerl wrote: post #66
guessmyname wrote: post #9

I switched to macOS from Linux two weeks ago and I am starting to regret that decision. Most — if not all — the commands that I thought I had mastered after years working on Linux environments stopped working because their BSD counterparts have slightly differences that completely break everything I try to do. It is even more frustrating when I realize that I have to deactivate security features built-in the new Appl…

What made you switch to MacOS?

Not the OP, but the reason I switched to the Mac 12 years ago (and never looked back) was to bring together my nerdy, creative, and "end user" sides under a single OS.

I'd been using mostly Linux on the desktop since 1996, I manage servers for a living and couldn't live without a terminal. That's the nerdy side.

On the other hand, I was serious enough with photography and electronic music production to need best of breed tools, which are still largely Windows and Mac-only to this day.

There's also a time for everything, and there are days when regardless of your computing skills, you need your creative person/end user hat on and apps that "just work" to keep your right brain fully focused on the end result (e.g. "No thanks, I'm not going to get distracted compiling some Gimp plugin to get red-eye removal", which may or may not have changed since I last tried)

MacOS, in spite of its recent slight drop in quality, is still second to none in satisfying all these requirements at once.

Re: Htop explained

#99

Post by Morpheus_ro »

Morpheus_ro wrote: post #20
TeMPOraL wrote: post #3

Thank you! Great writeup! I applaud the way you approached it - figuring out every single thing about a tool. Also, I didn't know about 'od' command. Thanks again!

please do explain in 2 words the od command. I was looking on the page and there is only one od command and it is not explained. thank you

I really didn't know about this command ... is it that bad to give me -1? ... I will never ask again here because of this and in the same time thank you you to the guys that actually lost some time to explain.

Re: Htop explained

#100

Post by vsl »

superchink wrote: post #71
gregmac wrote: post #51

Earlier quoted context omitted.

One of the things that I really dislike about homebrew is its refusal to run via sudo plus the requirement that you own /usr/local. This means: 1) It is a security hole; any application can now modify system-wide applications at any time. 2) You can't have multiple users able to use homebrew. I was expecting homebrew to be something similar to apt/yum/etc, but this makes it pretty fundamentally different. How does Ma…

This is no longer the case, as of Homebrew 1.0. See this change: https://github.com/Homebrew/brew/pull/896

This is only about /usr/local itself, not the directories under it, the one with executables - that's still owned by you, not root. Some difference in ease of initial installation, zero difference in terms of (in)security.
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