What is transparent hugepage (THP) and how to check THP usage per process in Linux (Explained)

Hugepages is a feature that allows the Linux kernel to utilise the multiple page size capabilities of modern hardware architectures. Memory is managed in blocks known as pages. A page is 4096 bytes. 1MB of memory is equal to 256 pages; 1GB of memory is equal to 256,000 pages, etc. To get the page size … Read more

Tutorial/Cheatsheet: Begineer’s Guide to Understanding Device Mapper Multipath for Linux

Tutorial/Cheatsheet: Begineer's Guide to Understanding Device Mapper Multipath for Linux

Before starting with going into the various commands we use for multipath let me give you a overview of multipath Without DM Multipath, each path from a server node to a storage controller is treated by the system as a separate device, even when the I/O path connects the same server node to the same … Read more

10 examples to customize or change the login prompt using PS1 variable of bash shell in Linux

10 examples to customize or change the login prompt using PS1 variable of bash shell in Linux

After your Linux node boots up and once you enter your username and password, you are provided with a shell prompt which looks something like below my-linux-setup:~ # When  executing interactively, bash displays the primary prompt PS1 when it is ready to read a command, and the secondary prompt PS2 when it needs more input … Read more

Tutorial / Cheatsheet:12 practical examples for different sudo access based scenarios in RHEL 7 / CentOS 7

Tutorial / Cheatsheet:12 practical examples for different sudo access based scenarios in RHEL 7 / CentOS 7

Below are some of the scenarios I can think of where sudoers file can be used, if you have any more questions for which you want any help of post us here in the comment section and I can try to update the article with more example scenarios To understand more on every syntax used … Read more

Tutorial / Cheatsheet: 11 examples to use systemctl to manage unit files and service in RHEL 7 / CentOS 7

Tutorial / Cheatsheet: 11 examples to use systemctl to manage unit files and service in RHEL 7 / CentOS 7

In my last article I have given an overview of systemd with examples. If you want to have a background of migration from sysvinit scripts which we were using RHEL 6 and earlier to systemd used in RHEL 7 then follow below link Everything you must know before starting with systemd in RHEL 7 / CentOS 7 … Read more

10 Basic examples of SED to perform per line action (print/delete)

In this article I will show you various sed expressions which can be used and combined to print or delete specific line from a file IMPORTANT NOTE: My examples provided are only to print the action performed, to use the same for delete action remove ‘-n’ and replace ‘p’ with ‘d’ on individual command To … Read more