I’ve been doing some benchmarking to try and understand write performance on Linux, and I don’t understand the results I got (I’m using ext4 on Ubuntu 17.04, though I’m more interested in understanding ext4 if anything, than I am in comparing filesystems). Specifically, I understand th…
Tag: filesystems
How to create a “fake filesystem” that forwards system calls to my program?
I would like to write a tool that can be used to mount archives such as tar, tgz, zip, 7z, etc. to some directory for as long as it’s running, such that I can then open it with whatever file manager I want. To do this, I would somehow need to make a fake filesystem that forwards system calls such
Access files on linux from nodejs with case insensitivity
I am accessing files from nodejs dynamically, but I am facing a problem when user creates a directory with different case like (/hello) and try to access it with different case like (/Hello). Is there a way that I can access directories on linux through nodejs with case insensitivity? Answer On a case-insensi…
How to restrict PHP file access to execution directory?
I have a bunch of PHP scripts inside of, say, /public_html/mydir/, and these scripts may possibly try to delete files / do other stuff to the filesystem. I want to allow all filesystem modifications within the /public_html/mydir/ directory, but any access (or deletion) outside of the mydir directory shouild n…
Reading a file kills NIC interrupts
I have a very strange problem with a board based on a MIPS processor and Linux 2.6. There are NIC interrupts for all incoming Ethernet packets. If I send 10.000 packets I could see that 10.000 NIC interrupts occurred. However, after I open and close a file (filled with zeros or regular) in the filesystem, the…
Where are inodes stored at?
I recently started learning about the Linux kernel and I just learned about inodes, which are data-structures containing meta-data of a file. Now, how do the OS find the associated inode of a file? (Let’s say a string of a path). Moreover, where are those inode stored at? I mean, obviously they are stor…
What should the “share” subdirectory contain?
When one has installed a library and look at what its repository contain, he may find something like that: repo/ bin/ lib/ share/ What the “share” repository should contain in general? Are there other types of subdirectories? Thanks! Answer The “share” word is used because what is unde…
Accessing files outside the root directing
My client asked me to do a website where a user can enter a path on the machine, PHP should scan the path and load all the media files in the directory and subdirectories. The user can enter any path, Desktop, or external drives, whatever, outside the root directory. That’s what the client wants and he&…
Optimal way of writing to append-only files on an SSD
I want to know what’s the optimal way to log to an SSD. Think of something like a database log, where you’re writing append-only, but you also have to fsync() every transaction or few transactions to ensure application level data durability. I’m going to give some background on how SSDs work…
Library installation with yocto recipe
have a bit of a problem creating a recipe for yocto. More specifically i have to install a library from git that normally installs like this: My question is how can I add this to the recipe functions do_configure, do_compile, do_install. Haven’t found much information or examples online. Update 1: This …