I saw something peculiar the other day. Hallucination? The microsoft.com domain was serving up 192.168.1.0 and 192.168.1.1 as A records in a 7 address round robin.

That’s a spooky reminder to check your rebinding setup — that is, if you’re playing with fire (DNS).

For example, unbound with private-address and private-domain. Then test if DNS rebinding is possible.

Are the caches warmed up? vmtouch and fincore are two useful programs.

What do they do? Basically, one can peek at what’s been cached into memory. I somehow ended up re–looking into this today. The Linux kernel is intelligent.

Many fortnights ago, I foolishly thought writing a GTK3 theme from scratch would be easy. It was mostly CSS unlike GTK2. About 40 minutes in came a horrifying realization: there’s fundamentally (and definitively) no way to write a consistent theme that works reliably with every application. The minor upside was a working (and somewhat accessible) wireframe theme and a basic understanding of debugging. The end.

GTK_DEBUG=interactive firefox

An actual but where did my Linux memory go command;
This program (repositories) came in handy while helping someone resolve an oom problem. Want to see memory usage and shared memory, perhaps sorted by swap?

smem -s swap -kta
smem --sort swap --abbreviate --totals --autosize

swap     (amount of swap space consumed ignoring sharing)
command  (process command line)
maps     (total mappings count)
name     (process name)
pid      (process id #)
user     (process owner)
pss      (proportional set size including sharing)
rss      (resident set size ignoring sharing)
uss      (unique set size)
vss      (virtual set size; total virtual memory mapped)

df -h | grep tmpfs
df --human-readable | grep tmpfs