Performance on iniy.org

Kubernetes Requests and Limits explained

Fri, 02 Feb 2024 19:39:46 +0000

During my work as IT freelancer I frequently I encounter common misunderstandings about the kubernetes requests and limits which lead to unstable systems and wasted resources.

So this blogpost explains what the meaning of the different values is and how to set them properly.

Guide to limits.conf / ulimit /open file descriptors under linux

Fri, 04 Jul 2014 18:43:00 +0000

Why does linux have an open-file-limit?

The open-file-limit exists to prevent users/process to use up all resources on a machine. Every file-descriptor uses a certain amount of RAM and a malicious or malfunctioning program could bring down the whole server.

nagios checks too slow

Tue, 30 Nov 2010 21:51:12 +0000

lately i came across a really dumb problem. Our nagios server sucked like hell and I couldn’t find the source of the problem. I was tuning nagios-parameters but nothing changed. The server had low load and cpu-usage, but the checks were delayed about 15-30 minutes (should be checked every 2 minutes). Then I found the solution. nagios active hostchecks YOU HAVE TO DISABLE THIS CRAP. In Nagios 2.x the hostchecks are serial, thus delaying all other checks, while checking. With some hundreds hosts it can happen fast, that the server is almost only checking the hosts and not doing anything else.

Find slow-queries in MySQL

Wed, 14 Oct 2009 21:26:31 +0000

Often when a web-application seems slow it’s not (or not only) the parse time, but also or mayorly database speed. Most scripting-languages don’t act “intelligent” in parsing as it would be best for user experience, but go through the code line by line (whom would expect it otherwise?). So if you have a website containing some slow MySQL-Queries it seems as if all the page just takes a eternity to load. One step would be to put all the page loading into some seperate code-piece and load it later with ajax-technology. This gives a great boost in user-experienced speed, because the most parts of the website load and are already usable before the database content pops in. But otherwise often not the database is the problem, but bad written querys. But how to find them? Luckily mysql already provides us with a feature called slow-query-log which can be activated easily through my.cnf. So just look for this: