New Tool: lsds – List All Linux Block Devices and Settings in One Place

I always wanted the /dev/zero character device driver, which you can map into memory to clear it, or use as an infinite source of nulls, to use the minor node number as the value that got mapped into memory or produced, so you could make an infinite source of beeps with:

mknod /dev/seven c 1 7

I wonder what would happen if you made a /dev/seven device in your http servers public_html directory? Would it dutifully serve it up?

Better yet, support for utf-8 unicode, so you can make an infinite source of poo emojis.

The "Everything Is A File" philosophy should be taken to its logical conclusion.

Thanks! Yep I was thinking of doing that next, will be very easy as under the hood the data is stored in Python dictionaries.

I just added a little comment/errata regarding the NVME_QDEPTH column to the post (search for errata). I should probably rename that column to emphasize that (for now) it’s the Linux nvme module level max QD and not the hardware one (it’s complicated…)

Hi, yep lsblk targets a wider area of functionality, like showing mountpoints, device UUIDs, while lsds focuses only on block device settings.

Maybe the latest Linux versions have lsblk versions that support these columns, but in RHEL9 at least I don't see equivalents to lsds'es WBT_LAT, QDEPTH (not the same as lsblk's RQ-SIZE), WCACHE, FUA and some others. But these 4 are which I regularly need (especially when troubleshooting a yet another slow fsync() issue etc). I did and do use lsblk all the time too, but still end up catting and grepping various additional files and correlating the results, sometimes on systems with 100+ multipath block devices.

The other reason was that I wanted a tool that shows me where it gets these values too (for myself and sometimes for explaining stuff to others).

Edit: That being said, it shouldn't be hard at all to add the said extra fields to lsblk too.

Rewrote most of the functionality in C as an exercise

https://gist.github.com/grahameger/2507019334f07036f84080a87...