Among other things, I'm a recreational bicyclist, and as this I'ma fan of basic wired cycling computers , which in their ownway are fascinating artifacts. A wired cycling computer is a littleelectronic device with an LCD display that shows you things likeyour current speed, how far you've come on this trip, the time, andso on (generally not all at once; typically there are several screensand you switch between them with a button). A wired bike computergets all

When I started writing my entry on the persistence of 'san' namesover several generations of our fileservers ,I believed that we'd considered our iSCSI environment to be 'not areal SAN ',with the last real SAN we operated being our pre-ZFS Fibre Channel environment. A largepart of it was that this was how I thought about those old fileservergenerations now, at this distance from them; I felt that our iSCSIenvironment was kind of a pseudo-SAN. When I actually read what

Recently I wrote about the persistence of 'san' names over severalgenerations of our fileservers , even thoughwe don't have a SAN any more. In the process of writing that entry, I discovered thatI'd forgotten various details of how our first generation and second generation of ZFS fileservers worked and howwe talked about them, and a lot of details about our pre-ZFSfileserver environment. At the time we were operating each of theseenvironments, all of this was obvious to us so we didn

Recently, I had an experience with Bash (and not for thefirst time with this sort of thing):

Dear bash: if you have a path for a command cached and trying toexecute that file gets ENOENT, perhaps you should, you know, *check$PATH again*?

Then I endorsed getting rid of shell command hashing .

Once upon a time, Unix computers were slow, system calls were slow,Unix kernels only cached simple things, RAM was small relative tothe size of directories, $

Back when I wrote about how the mere 'presence' of a URL on a webserver wasn't a good signal , Icasually mentioned that you were more likely to have everythinganswered with a HTTP 200 status on things that weren't really 'webservers' as such, but which were just using HTTP. You might ask whyyou'd use HTTP if you weren't a web server, and the answer isstraightforward and widely known: HTTP has become the de factodefault communication

Today I said something on the Fediverse :

Today my co-worker discovered that the SLURM job scheduler requiresyour hyperthreading to be uniform across your CPU cores. Our latestSLURM GPU nodes have Intel hybrid CPUs, which aren't uniform; theyhave 24 cores but 32 threads total, because only the 8 performancecores are hyperthreaded.

I guess we'll turn off hyperthreading. Thanks, Intel and SLURM.

(I'm sure people are going to discover much more fun with this.)

These new

These days, modern versions of su interpret 'su -' as 'su -l' ( via ). Although they have differentimplementations of su , this is true on Linux , FreeBSD , and OpenBSD . However, it turns out that thisfeature wasn't always in Unix's su.

The V7 su(1) is quite minimal, and has no equivalent of '-' or '-l'. In fact,V7 su takes no options at all; it treats its first

A while back, I read Tristan Hume's Production Twitter on OneMachine? 100Gbps NICs and NVMe are fast ( via ),which goes through the mental exercise of sketching out such athing. As part of this, Hume must assess the size of individualtweets, and if you were doing this for the Fediverse, you'd wantto assess the size of individual posts there. Fediverse posts onmy current server are limited to 500 characters, so things looksimple. But reading

Yesterday I wrote about a criticism of the usual static versusdynamic website divide , where I noteda number of (what I see as) significant differences between staticand dynamic websites in practice. But there is another importantdifference in practice, and that's the amount of expertise that'sneeded to create each of them. Specifically, static websites don'trequire much expertise to create . Given a suitable general webserver environment, which is easy to provide, all you need to setup a static website