My brush with the increasing pervasiveness of smartphone GPS mapping
One of the things I do with my time is go bicycling with a localbike club . When you go on group bike rides, oneof the things you generally want to have is directions for wherethe ride is going (if only to reassure yourself if you get separatedfrom the group). When I started with the club back in 2006, these'cue sheets' for rides were entirely a paper thing and entirelyoffline; you turned up at the start of the ride and the ride leader
'Retail' versus 'wholesale' spam
A while back I mentioned that the spam received by my spamtrapSMTP server is boring ; it's mostly advanced feefrauds, phishes, and the like. In light of that and that GMail basedpeople keep trying to send me spam, I've been thinking about howone way to split up spam is between what I'll call retail spam andwholesale spam.
Wholesale spam is the high volume emitters, the people who are doingit in enough volume that they have real infrastructure and automationof some sort
Some data on how long it is between fetches of my Atom feed
Recently I became interested in a relatively simple question: onaverage, how much time passes between two fetches of the Atom feedfor Wandering Thoughts ? Today I want to give some preliminaryanswers to that. To make life simple, I'm looking only at theblog's main feed and I'm taking 24 hours of data over Friday (localtime). Excluding feed fetch attempts that are blocked for somereason , I get the following numbers:
- the straight average is one fetch every 12.
Your standard input is a tty in a number of surprising cases
Every once in a while, someone writing a program decides thatchecking to see whether standard input is a tty (via isatty() )is a great way of determining 'am I being run interactively ornot?'. This certainly sounds like a good way to do this check ifyou aren't familiar with Unix and don't actually test any numberof situations, but in fact it is wrong almost all of the time.
For a start, this is wrong if your command is just being run
Eating memory in Python the easy way
As a system administrator, every so often I need to put a machineunder the stress of having a lot of its memory used. Sometimes thisis for testing how things respond to this before it happens duringlive usage; sometimes this is because putting a system under memorystress can cause it to do important things it doesn't otherwise do(such as reclaim extra memory). The traditional way to do this iswith a memory eater program, something that just allocates acontrolled amount of memory and then (usually
Mdb is so close to being a great tool for introspecting the kernel
The mdb debugger is the standard debugger on Solaris and Illumossystems (including OmniOS). One very important aspect of mdb isthat it has a lot of support for kernel 'debugging', which forordinary people actually means 'getting detailed status informationout of the kernel'. For instance, if you want to know a great dealabout where your kernel memory is going you're going to want the' ::kmastat ' mdb command.
Mdb is capable of some very powerful tricks because it lets you compose
Don't support shortened versions of your domain names in email addresses
I'll start with the basic background: the university here is dividedup into a lot of departments and divisions and groups and so on.Most of them have subdomains under our top level domain, for instance We have been providing email topeople for what is now quite a long time. Way I have nothing against OpenBSD in situations where it works well;we run it for firewalls and a few other narrow purposes which itdoes well at. But I have no love for it either and left to my owndevices I probably wouldn't use it for anything. Certainly I can'timagine running OpenBSD on a personal machine. Some of this is an extension of my pragmatic and technical viewson FreeBSD versus Linux , with a bit of thecultural bad blood thrown in as well.Some of it is It's early Sunday morning, which is the time when Fedora kicks offits weekly checks of MD arrays. I know this time extremely well, notbecause it causes visible IO load but because I actually watch my kernelmessages and software RAID floods them during this check. And by that Imean that roughly once every five seconds I can look forward to a burstof messages like this: We use OpenBSD here for firewalls and a few other things, andover the course of doing so we've found a number of bugs and issues .Have we ever reported these to the OpenBSD people? Ha ha. Of course not. We'd have to be crazy to do that. The OpenBSD culture has acquired a reputation for being what wecould politely call 'abrasive'. But let's call a spade a spade andsay 'abusive' instead. As the folklore has it, if you cs.utoronto.ca (and then hosts under their subdomain), and many ofthem run (or ran) their own email systems, creating email addresseslike
My personal view of OpenBSD
A Linux software RAID message flood
md: delaying data-check of md51 until md53 has finished (they share one or more physical units
OpenBSD and the impact of culture
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