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How do you manage mailing lists?

Filed under: Question,sysadmin — Thomas @ 17:00


Every new year is a time of cleaning. After getting back to Inbox 0, my next target is my mailing list subscriptions.

It must be something psychological, but I cannot bring myself to unsubscribe from some of these mailing lists. I don't check on them daily, but once in a while it's darn useful to search through my local copy of mails on, say, selinux, and find solutions for a problem I'm having.

However, all this mailing list mail brings me a lot of headache. My email client is slow, and I would want it to be fast for the real mail I'm getting (from actual people, needing actual work). It's hard to track the mails that matter - all my list mail gets put into folders automatically with some procmail magic, but it also means that some of the things I should be paying more attention to are just another bold folder in Evolution somewhere down the mail tree. And lastly, the server where I host my mail shared with friends gets too much traffic, and syncing 3 different evolutions over IMAP with it is a big part of the burden.

I vastly prefered the newsreader model of old, and I think the de facto standard of mailing lists really is a mistake. But I'm not sure what to replace it with.

What I want:

  1. have selected mailing list archives be available on my machines, locally
  2. have them synced/updated automatically
  3. have them out of the way of my normal mail usage unless when I need them

I've been considering getting a separate email account just for email lists for this purpose, although I don't look forward much to having to change all my subscriptions, and would first like to hear from other people how this approach works out for them.

There used to be a push towards web-based mailing list subscriptions, but I don't know if anyone is really seriously using that, and I would like to have the option of reading these mailing list archives offline.

How do you separate your 'real' mail from your mailing list mail? How do you handle them?

kslowd000 and friends

Filed under: Question,sysadmin — Thomas @ 20:43


Ever since upgrading to Fedora 14 my desktop felt sluggish. It was more than the typical boiling frog kind of sluggishness, where you get the feeling everything's snappy just after you bought a new fancy computer and install it freshly with a recent OS, and over time performance slowly degrades until you wonder why computers are always so slow. Sure, it looks like Evolution, after a round of improvements in memory management, has gone back to being a memory hog. But this time, it was more. It would go through short phases of unresponsiveness and then come back. Load would be consistently around 1 or more, but for no apparent reason at all.

After a while watching top, I noticed a process called kslowd[xxx] jumping up and down in the top output regularly. The k says it's a kernel process. No idea what it is. Googling isn't very helpful to learn what it actually is, but it did put me on the trail because there are huge amounts of posts on sites and mailing lists about this process eating CPU time and slowing down the computer.

After a bunch of reading some post suggested it might be this patch by Dave Airlie, a name I recognize, to the kernel. I took the Fedora kernel src.rpm, spent a few minutes getting acquainted with Fedora's kernel spec layout de l'année, integrated the patch, rebooted, and voila. No more kslowd000 eating all my CPU.

I recently found this workaround which I'll try next time the kernel gets upgraded.

That still doesn't tell me what that kernel process is supposed to be doing (anyone up for a mandatory rule of having man pages for kernel processes too ?), so feel free to comment!

long life external batteries for laptops ?

Filed under: Question,Travel — Thomas @ 19:19


I'm probably going to be doing some long flights pretty soon and I'd like to maximize my laptop time hacking on the plane.

Who of you have experience with big external batteries, what's a good one to get, how long can I expect them to last and how long do they take to charge ?

Low cost per core

Filed under: Question,sysadmin,Work — Thomas @ 12:16


For work, I'm re-reviewing servers and systems with the simple-but-not-easy goal of lowering the basic monthly cost per core. The world of racks, servers, CPU's and cores is a more complicated place than it was a few years ago, since in a few U's you can put anything from a bunch of small cheap servers up to monster boards with four CPU sockets and 12 core CPU's for a total of 48 CPU's in a 2U space. And a look at a Blade system still makes me drool, although I'm still not sure in what case a Blade really makes sense.

In any case, I tried to do a little comparison (which is hard, because you end up comparing apples and oranges) using Dell's online configurator.

On the one hand, filling racks with Poweredge R810, 4 x 8 core 1.86 GHz, Intel XeonL7555 machines, gets the price down 26 euro per core per month. Doing the same with Opterons, which surely aren't as powerful as the Intel ones, I can get a Poweredge R815, 48 cores quad Opteron 2.2 GHz, 6174, for 48 cores total, at 9.53 euro per core per month.

And then I thought a Blade would be an even better deal, but it turns out that it isn't really. The cost per core, with similar CPU's, really did come out pretty much the same as the R810 based solution. Probably not that surprising in the end since if you fill a machine with cores, the CPU cost will start dominating. But somehow I thought that Blades would end up being cheaper for maximum core power.

Maybe I'm approaching this the wrong way ? If the main concern is cost per core in a datacenter, how would you go about selecting systems ?

e-book reader wishlist

Filed under: Question — Thomas @ 19:44


5 things I want from an ebook reader:

  • I should be able to take notes while reading. Bonus points for having decent OCR so later on my notes are searchable.
  • I want to use it to learn languages. So I want to read a book in Spanish, and words should be clickable or stylusoverable and give me the English translation. It's my number one annoyance when reading paper books in new languages, and I don't want to lug a dictionary around.
  • I want it to be easy to get books onto it based on my Facebook reading list, Amazon wishlist, O'Reilly bookshelf, ...
  • I want to be able to put my own texts on it; pdfs I've downloaded, manuals we make, .... No proprietary formats please.
  • I should be able to do this stuff from Linux.

Obviously this goes on top of normal requirements like 'be light enough to carry around in addition to my usual laptop' (I usually carry a book as well so that should be no problem) and 'have decent battery life'.

Does this already exist ? Can I buy it in Europe ?

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