One of the differences between X and Wayland is that in theclassical version of X you send drawing commands to the server whilein Wayland you send images ;this can be called server side rendering versus client siderendering . Client side rendering doesn't preclude a 'networktransparent' display protocol, but it does mean that you're shippingaround images instead of drawing commands. Is this less efficient?In thinking about it recently, I realized that the answer is thatit depends on a number of things.

Let

Suppose that you have a shell script that's not necessarily complexbut is at least long. For reliability, you use 'set -e' so that thescript will immediately stop on any unexpected errors from commands,and sometimes this happens. Since this isn't supposed to happen, itwould be nice to print some useful information about what went wrong,such as where it happened, what the failing command's exit status was,and what the command was. The good news is that if you

Over on the Fediverse, I shared an unhappy learning experience :

Linux kernel NFS: we don't have mandatory locks.
Also Linux kernel NFS: if the server has delegated a file to a NFSclient that's now not responding, good luck writing to the file fromany other machine. Your writes will hang.

NFS v4 delegations arean feature where the NFS server, such as your Linux fileserver , hands a lot of authority over a particularfile over to a client that is using that file.

Among computer geeks, myself included, there's a long runningoptimistic belief that projects can be considered in isolation and'evaluated on their own merits', divorced from the specific peopleor organizations that are involved with them and the culture thatthey have created . At best, this viewimagines that we can treat everyone involved in the development ofsomething as a reliable Vulcan, driven entirely by cold logic withno human sentiment involved. This is demonstrably false (ask anyoneabout the sharp edge of Linus Torvalds' emails

We have a long standing system to monitor the temperatures of ourmachine rooms and alert us if there are problems . A recent discussion about the stateof the temperature in one of them made me realize that we want tomonitor and alert for two different problems, and because they'redifferent we need two different sorts of alerts in our monitoringsystem .

The first, obvious problem is a machine room AC failure, where theAC shuts off or becomes almost completely ineffective. In our machinerooms, an AC failure causes

We recently had a big downtimeat work where part of the work was me doing a relatively complexand touchy thing. Naturally I made a checklist ,but also naturally my checklist turned out to be incomplete, withsome things I'd forgotten and some steps that weren't quite rightor complete. This is a good illustration that checklists are hardto create.

Checklists are hard partly because they require us to try to remember,reconstruct, and understand everything in what's often a relativelycomplex system that is

One of my little web twitches is the lax handling of unknown queryparameters . As part of this twitch I'velong been a bit irritated that Apache accepts query parameters evenon static files, when they definitely have no meaning at all. Youcould say that this is merely Apache being accepting in general,but recently I noticed a combination of Apache features that canprovide an additional reason for Apache to do this.

Apache has various features to redirect from old URLs on your siteto new URLs, such as Redirect

Suppose that you're on Ubuntu 24.04, using NFS v4 filesystems mountedfrom a Linux NFS fileserver , and at some pointyou do a 'ls -l' or a 'ls -ld' of something you don't own. You may thenbe confused and angered:

; /bin/ls -ld ckstst/bin/ls: ckstst: Permission denieddrwx------ 64 ckstst [...] 131 Jul 17 12

These days, there's an unusually large plague of web crawlers, manyof them attributed to LLM activities and most of them actinganonymously, with forged user agents and sometimes widely distributedsource IPs. Recently I've been using two tools more and more to tryto identify and assess suspicious traffic sources.

The first tool is Anarcat's asncounter . Asncounter takes IPaddresses, for example from your web server logs, and maps them to ASNs (roughly who owns an IP address) and to CIDR netblocks that