The details behind zpool list's new fragmentation percentage
In this entry I explained that zpool list 's new FRAG field is a measure of how fragmentedthe free space in the pool is, but I ignored all of the actualdetails. Today it's time to fix that, and to throw in the generalbackground on top of it. So first we need to start by talkingabout free (disk) space.
All filesystems need to keep track of free disk space somehow. ZFSdoes so using a number of metaslabs , each of which has a spacemap
One limit to how much TLS can do for you against MITM attacks
One of the bits of TLS news recently has been that Kazakhstan isapparently planning to force all Internet users in the country toinstall a new TLS root certificate (see eg here and here )and then probably use that certificate to intercept whatever HTTPScommunication they want to. This situation points out what is notso much a limitation of TLS and encryption in general as a simpleabsence of magic.
The obvious assumption to make is that the Kazakhstan authoritiesare going to end up blocking HTTPS connections that aren't willingto
What zpool list's new FRAG fragmentation percentage means
Recent versions of ' zpool list ' on Illumos (and elsewhere) haveadded a new field of information called 'FRAG', reported as apercentage, which the zpool manpage will tell you is 'the amountof fragmentation in the pool'. To put it politely, this is veryunder-documented (and in a misleading way). Based on an expeditioninto the current Illumos kernel code, as far as I can tell:
zpool list's FRAG value is an abstract measure of how fragmentedthe free
Red Hat has really doubled down on being email spammers
Back in June, I wrote about how we'd gotten marketing email fromRed Hat to a RHN contact address . At the timeI wrote an angry complaint email to Red Hat about it, from my coreemail address. This is the only time I have given Red Hat my coreemail address; it is not, for example, the address I use on theirBugzilla.
On November 10th, I got the following email message from Red Hat,once again from their very own SMTP server:
From
My current dilemma: is it worth putting the root filesystem on a SSD
Due mostly to an extremely good deal at the end of last week, I'mgetting a mirrored pair of 250 GB SSDs to add to my work machine.As 250 GB is not enough to hold all of the data that's currentlyon the machine, I'm going to have to be selective about what I puton the SSDs. Which leads to the question I'm currently considering;whether or not it's worth putting my machine's system filesystem onthe
A new piece of my environment: xcape, an X modifier key modifier
I was turned on to xcape by evaryont in a comment on my entry on myBackspace/Delete X key mapping shift .What xcape does is, well, let's quote from its own readme:
xcape allows you to use a modifier key as another key when pressed andreleased on its own.
A modifier key here is things like Shift, Control, and Alt (andCapsLock if you turn it into a modifier, such as making it anotherControl). The common use of xcape is by vi people
My feelings about my mechanical mini keyboard
I wrote a while back about my temptation to find a good USB minikeyboard to replace my old PS/2 mini keyboard .Well, I recently gave in to that temptation and got a mechanicalmini keyboard, specifically the Matias Mini Quiet Pro , which seemed like close to thebest candidate I could find. Although I've only been using it fora few weeks, I want to write my initial feelings down now beforemy memories of what it was like to use my old keyboard fade toomuch.
In
A thought on the apparent popularity of new static typing languages
It all started with Elben Shira's The End of Dynamic Languages , whichsparked Have Static Languages Won? ( via )from Maxime Chevalier-Boisvert. In that I read the following:
Like [Elben Shira], I've noticed that despite the fact that therehave been an enormous number of new programming languages coming out recently, the overwhelming majority of them are staticallytyped. [...]
I'm an outsider bystander on all of this, but it strikes me thatone possible contributing reason
Documentation should explain why things are security issues, at least briefly
In my discussion of Apache suexec Imentioned the apache2-suexec-custom Debian package, which allowsyou to change suexec's idea of its docroot and thus use suexecto run virtual host CGIs that aren't located under /var/www . Ifyou're using suexec-custom, one of the obvious questions is whatit's safe to set the suexec docroot to. If you read the manpage,you will hit this paragraph:
Do not set the [suexec] document root to a
Some notes on Apache's suexec
We've recently been wrestling with suexec in an attempt to get itto do something that it seemed that suexec would do. As a resultof that learning experience, I feel like writing down some thingsabout suexec. You may wish to also read the official Apachedocumentation on suexec ,but note that you may have to pay close attention to some of thethings that it says (and a few things appear to be outright wrong).
Suexec has two modes:
- Running
/~/.. Menu