Server load. Services?

Question

linux

Goodnight.
There is a server with installed debian and ISP Manager.
Everything would be fine, entering the top command in the console or this plugin for ISP ...
BUT. You need to get constant server statistics (RAM, processor, processes themselves) of each user. Constant i.e. some service that visually demonstrates this data, whether in the console or in the logs, it is quite detailed and clear. And most importantly - with a certain update interval.
Gentlemen, system administrators, please advise a program or some script for Debian, with which you can monitor the server load in the most convenient and detailed form.
Thanks

Answer 1

pinba, munin, cacti and many others.

Answer 2

Obtaining complete and reliable data on the consumption of server resources (RAM, CPU) by each USER on linux and freebsd is impossible. You can take instant statistics once every N minutes (for example, from ps), and assume that this reflects the real picture =) In reality, the process can work out in the interval between collecting statistics, devour all the resources and end without leaving any traces. Or, for example, to eat other resources - hard disk iops, not giving a load on the percentage, but loading the entire system. Or, if we are talking about hosting, making queries to mysql, for which they are shot in wartime.
On the other hand (as it happens in any cpanel), it is enough for Google with Yandex to go to the site, as the limits for instant overload on the processor will work, which (depending on the settings) can lead to an immediate blocking of hosting.
However, let's not talk about sad things =) You can and should take instant data, anyway, there is nothing else left. Ready-made monitoring systems in visualizing this data are unlikely to help you with this, with the possible exception of Cacti, a bunch of scripts and a large file - the number of users in the system may change, and even in cacti you will have to press refresh

Answer 3

it is strange that no one suggested sar ... - it is allowed to collect various (mostly iron) statistics at any intervals, the required amount of time. the program is very powerful. man sar