Vinod Kurup

Hospitalist/programmer in search of the meaning of life

Nov 17, 2019 - 2 minute read - Comments - family programming

Ports and networks

Kavi was looking over my shoulder as I tried to get my blog working in a local Docker container. I’ve gotten to the point that the site seems to be up and running in the container, but I can’t seem to get to it from my laptop. So, he wondered why I was putting port 1313 in my URL bar (“localhost:1313”) and then I showed the results of netstat -ant to prove that something should be listening on that port. And we got the IP address for and then put that in Chrome’s URL bar with :80 at the end of it, and magically, it worked. (Other websites did not work, and I explained that most sites will not allow their sites to be accessed via IP address).

I still haven’t figured out why I can’t access the blog running in my container, but I think Kavi’s learning more about networking than I ever did (and I’m hoping that he’ll be able to debug these issues for me… soon enough)

UPDATE: I figured it out. Hugo’s server was listening on localhost inside the container, when it needed to be listening on Adding that as a --bind parameter fixed the issue (though I had to also add --baseURL and --appendPort=false params, which saddened me.)

Nov 17, 2019 - 2 minute read - Comments - blog


I moved my blog from Octopress to Hugo today. I had been slightly unhappy with Octopress for a while now, but mainly I just wanted something new to play with. Hugo is MUCH faster than Octopress was:

vkurup@caktus020:~/dev/ $ hugo

                   | EN   
  Pages            | 669  
  Paginator pages  |  29  
  Non-page files   |   0  
  Static files     | 426  
  Processed images |   0  
  Aliases          |   1  
  Sitemaps         |   1  
  Cleaned          |   0  

Total in 808 ms

It is nice to generate my entire site in less than a second.

But I still liked the style and theme of my old site, so I was happy to find that someone had already built an Octopress theme for Hugo. I promptly stole his work and customized a few things here and there to make it look (nearly) exactly like my old site did. Yay! Thanks to Parsia for building that theme. I’ve also subscribed to his RSS feed because his site looks pretty interesting.

Moving my content wasn’t easy, but it wasn’t hard. I mainly just copied the old markdown posts over, changed the front matter, and then fixed a few octopress plugins I was using to work with Hugo.

Future steps:

  • Switch from Disqus to something self-hosted
  • Generate the HTML on the server rather than having the HTML in git
  • Update my About page and Computers page
  • … oh, maybe write more!

Apr 8, 2019 - 1 minute read - Comments - family poetry

Avik 7:30

“Here it comes!” His eyes light up.
Slurps one last sip from his small cup.

Then bounding from the kitchen table,
Fast as lighting, he is able

To trash his scraps and stow his dishes.
He yells to Mom, “It was delicious!”

One more breath then on the couch he lands.
“What’s up?” says Mom. Dad shrugs his hands.

Big brother also has no idea.
Big sister sighs, “He’s a weird one I fear.”

We gather round to be sure he’s fine.
Eyes glued to his wrist, “It’s 7:29!”

And then the beeping fills the room.
The smile confirms he’s over the moon.

The source of this happiness, on his arm,
His brand new watch, and a 7:30 alarm.

(A real-life story, barely embellished)

A kid with a watch A kid with a watch

Dec 20, 2018 - 2 minute read - Comments - running family

Triangle Race Series

When we made our 2018 goals last year, Kavi, Anika and I all had some running-related goals. I don’t remember offhand exactly what each of our goals were, but I think we all wanted to run more races, because well, races are fun! I somehow stumbled on the Triangle Race Series. It’s a series of a couple dozen races throughout the year around the Triangle, so we signed up for a few. They keep standings based on participation and placement. You get 5 points for running a race, and more if you place in your age/gender division. We ran about 4 or 5 of the races. I hadn’t really thought about the series at all recently since I injured my right Achilles in July and haven’t run at all since then. Getting old really is a bummer. Anyways, I checked the website today and they have posted the final 2018 results. I got 6th place in my “not-quite-old-fogey” division! Not bad, huh? Yeah, I know… it’s mostly a participation award, but still, I’m proud. But wait! That’s not even the best part. I’m even more proud of Kavi and Anika. They are both in the 0-19 age group, so get to compete against teenagers. Kavi got 3rd place in the male 0-19 division, and Anika got 1st place in the female 0-19 division!

Oak City Mile 2018 Oak City Mile 2018

Dec 2, 2018 - 5 minute read - Comments - home

My Nest Journey

I got 2 Nest E thermostats because Duke Energy was having a sale around Black Friday. I didn’t have any strong motivation to have a Nest. The idea of a smart home is cool, but most ‘smart’ things nowadays have ended up being more work than benefit. Anyway, for $75 each, I thought it was worth a try. We have 2 thermostats so I decided to install the upstairs thermostat first. The process started off smooth and easy. I like that they provide a back plate, which I didn’t even notice until my trusty assistant, Kavi, pointed it out. My existing Honeywell thermostat is rectangular and if I just put the small circular Nest in its place, there would be a big chunk of unpainted real estate on the wall. Having the back plate prevented this from being a ‘replace thermostat, and learn how to patch and paint the wall’ project. The online Nest compatibility checker and the paper instruction manual (which includes stickers to label the existing wires) are also nice touches. That all gave me the (misguided?) confidence that even I could do this. A study confidence which lasted until I flipped the circuit breaker back on and …. nothing happened. According to the manual, the Nest was supposed to turn on, say Hi, and then walk me through the set up process. But it remained dead as a doorknob. I pulled it off the wall and plugged it in via USB (a nice troubleshooting feauture). It turned on and then when I placed it back on the wall, it complained that it was not getting enough power from the R wire. The error code was E195. When I looked at the ‘Technical Info’, it reported that the R wire was only providing 2-3 volts, while it needed 24. I chatted up Nest support, which took about 30 minutes to connect on a Friday night. The representative was responsive and useful. They eventually recommended trying to disconnect the C (common) wire. For a reason I still can’t explain, this brought the voltage on the R wire from 2-3 volts up to 35 volts, and my Nest was working.

Having tasted the sweet nectar of success, I then tried to swap my second Nest in for my downstairs thermostat. I made a huge mistake here. It had been easy to identify the circuit breaker for my upstairs furnance because it was labelled, “Up Furnace”. But there was nothing labelling the downstairs furnace. I switched off the circuit breaker that I thought was responsible for the downstairs HVAC, but in hindsight, I think I got the wrong one (and since it was warm out and the heater wasn’t running, I didn’t notice because nothing was running in the first place). Anyway, I walked through the rest of the instructions and again got to the point where the Nest was supposed to power on, but it didn’t. So I powered it on via USB and placed it back on the wall. Unfortunately, this time I was getting only 0.01 volts from the R line. Still, I was hoping that the ‘disconnect the C wire’ trick would work again. Unfortunately, disconnecting the C wire did nothing. I walked through things with Customer Service chat. Again, they were helpful (rather than just spouting cookbook-type basic info), but in the end, they didn’t have a recommendation that would fix things. They suggested that I get a voltmeter and test the voltage output at the various wires. I do not have a voltmeter and felt that I was getting in over my head, so instead I put in some calls to HVAC service companies, but since it was the weekend and this wasn’t urgent, I was resigned to having no heat over the weekend. I watched a few Youtube videos of HVAC repairs, some of which were quite entertaining. Eventually, I tried to reconnect my old Honeywell thermostat and was surprised and intrigued when this ALSO failed. It made me think that I messed something up somehow. The only thing I could think of was that since I hit the wrong circuit breaker, there was live current in the wires. While moving them from the Honeywell to the Nest, perhaps I touched 2 wires together causing the system to short circuit. I don’t remember noticing a spark or anything, but that was my best guess. I eventually watched enough videos to give myself confidence that I could open up the HVAC and find the electrical panel. I did that successfully (after turning off the CORRECT circuit breaker, and also pulling out the pull out switch next to the furnace). After cleaning out a ton of cobwebs, I found the LED light on the electrical panel was off (even after connecting the circuits temporarily). I searched the panel and found a 3-amp E fuse (like the kind I’ve seen in automobile fuseboxes). I pulled it out and sure enough, it was blown. It looked like the ‘bad fuse’ in this photo. Off to Home Depot, I purchased 2 replacements for 3 dollars, and then replaced the busted fuse with the new one. I flipped the circuit breaker and put the pull-in switch back in. The first encouraging sign was that the red LED light on the electrical panel turned on. I went inside and, joy of joys, the Nest was booting up and showed 35V via the R wire. So, I guess the bottom line is that I need to be more careful when I’m at the circuit breaker box.

Sep 23, 2018 - 2 minute read - Comments - family garden


Guess what, we’re composting now! I told you was going to be a gardener, so now you know I’m serious. For oh so many years, every Friday, we’d haul the garbage and recycling out and I’d think to myself, “Wow, we’d have like no garbage at all if we were composting.” It’s only taken a few years of thinking that, week in and week out, to get me to try. Actually, that’s not even true. It was still way down on my future to-do list until I got a cheap copy of “The Complete Idiot’s Guide to Composting”. Thank you, BookBub! (As if I needed any other incentive to buy and read more books). But honestly, the book was excellent in that it made me think that yes, even I could compost. So shortly after finishing it, I headed down to the Orange County Solid Waste Center and purchased an Earth Machine compost bin for fifty bucks, and made the kids set it up near the screen porch. We’ve been throwing all our copious kitchen scraps for the past 2 weeks. So far, all that has happened is that a bunch of fruit flies think we’re awesome neighbors and seem to have moved in for the long haul. But I’m hoping that some composting starts happening soon. It’s supposed to be easy as pie, but I’m secretly worried that I’m missing something, oh, like maybe skills or talent. But our garbage bin sure is lighter!

Sep 22, 2018 - 2 minute read - Comments - family garden

Starting a garden

I’m going to be a gardener. Yup, just decided. Well, re-decided, I guess, since we already have a garden. It’s a strip of dirt on the side of our house and we’ve been trying to grow vegetables the past couple years. But it has some problems. It’s way out of the way, so it’s a pain to check on it (since I’m lazy). The ground just underneath the topsoil is hard clay. It’s shaded most of the day either by our house, or by the beautiful forest surrounding our house. And I haven’t figured out a way to keep the deer from eating the few vegetables that we are able to grow in there. And even despite all those problems we’ve been able to grow some zucchini, okra, tomatoes and basil, which has been super exciting, and makes us want more! Here’s a photo of the harvest that greeted us when we returned from a week-long trip to visit my parents in Dallas this summer:

August Harvest August Harvest

But, in general, things end up getting eaten by the deer or overrun by weeds, so we’re trying a new approach now, based on the book, Square Foot Gardening. Kavi and Anika helped me build this raised bed, which is itself a huge accomplishment given how not-handy I am.

Our Little Garden Our Little Garden

This was my first time using a drill since shop class in high school! We’re going to try using a fishing line fence to keep the deer away. I’m not very optimistic about that, but fingers-crossed! We can also see the garden from our living room, so maybe I can just shoo them away any time they saunter by. The garden is looking quite pathetic because we bought some seedlings from the Carrboro Farmer’s Market but then all our garden plans got sidetracked by Hurricane Florence (which fortunately treated us very kindly, all things considered). So, the seedlings wilted away in our screen porch before we finally got a chance to plant them this week. We’re hoping there’s still some life left in them. Anyway, our expectations are low, especially given how late in the summer we’re starting, but it would be nice to get one head of lettuce or something to grow. I’ll be sure to let you know!

May 31, 2018 - 2 minute read - Comments - india education

History of Indian Civilization

I briefly mentioned finding the 2012 UCLA lecture series, “History of Indian Civilization", a couple days ago. I’m about halfway through and have found it thorougly illuminating. I learned a lot about India growing up, but never in a formal way, so it’s nice to have someone as skilled as Vinay Lal connect all the loose threads into a coherent history. One of the things that surprises me is that aside from the fact that classes are being streamed over the internet, there is nothing different than the lectures I skipped (I mean religiously attended!) about 20 years ago. It’s a large auditorium of students watching a very charismatic, knowledgeable speaker pacing at the front of the class, occasionally making mostly-legible markings on a chalkboard. Not that there’s anything wrong with that. I learned a lot back in college and I’m enjoying these lectures immensely. It just seems strange that so little has changed in the university clasroom (at least this one from 2012) when so much has changed in the world at large.

Actually, I find it reassuring that little has changed, at least in some classes. There was a time when the ability to download the audio of any university class was absolutely new. For me, that was around 2002 or so. I listened to CS61A (UC Berkley’s intro to CS course) and a few other similar courses back then. The limitations of internet bandwidth and storage made anything more than audio difficult back then. But now with those barriers crushed, I was afraid that everything would be “multimedia”, and not amenable to listening while I commute to work. So, it’s reassuring to find that audio-only dissemination of knowledge is still a thing.

May 30, 2018 - 2 minute read - Comments - programming postgresql

Autovacuum not running

OK, this is a debug session in progress, so don’t expect a nice solution at the end. We’re working on a project that does analysis of some public voter registration data. The DB is hosted on Amazon RDS and I’ve been perplexed by how poorly queries are performing there, despite the tables only have about 10 million rows. Simple queries are taking many minutes, which is orders of magnitude slower than my laptop.

Mark suggested running ‘VACUUM ANALYZE’, which I didn’t think would help because my understanding was that the autovacuum process in PostgreSQL would be taking care of that on a regular basis. These queries had been slow for days with no recent inserts or updates, so certainly autovacuum should have caught up to them by now. But, I tried it anyway and lo and behold:

db=> select count(*) from voter_ncvoter;
(1 row)
Time: 315777.051 ms
db=> vacuum analyze;
Time: 11377035.096 ms
db=> select count(*) from voter_ncvoter;
(1 row)
Time: 4300.107 ms

Woah, that worked! Sure, it took 3+ hours to run ANALYZE, but wow. So, why isn’t autovacuum automatically doing this for us. (I mean it has the phrase ‘auto’ in its name!!!)

I’ve found this great article on autovacuum basics which led me to do this query:

db=> select relname, n_live_tup, last_autoanalyze from pg_stat_all_tables where relname like 'voter_%';
       relname       | n_live_tup |       last_autoanalyze
 voter_changetracker |  306689271 | 2018-05-05 04:59:08.503876+00
 voter_filetracker   |         41 | 2018-05-13 02:00:47.802633+00
 voter_ncvhis        |          0 |
 voter_ncvoter       |   12336616 | 2018-05-06 13:20:30.073426+00
 voter_badlinerange  |        404 | 2018-04-10 05:44:39.949193+00
(5 rows)

So those 2 large tables haven’t been ANALYZEd in weeks, despite the fact that we import a 10 million row CSV once every week. This is the end of my debugging road, for now. Hopefully, I’ll figure out what’s going on.

May 29, 2018 - 2 minute read - Comments -

Renaissance Man

I love this post by Austin Kleon. As someone who has found very few things that I don’t find intriguing in some way, it is nice to know that there are others like me and that maybe there’s nothing wrong with that. I love being a doctor and I love being a programmer, and I love honing both of those crafts.

He also links to a 2012 New York Times article about a UCLA sophomore who spends 1 hour each day learning something new, mainly by taking online courses from other universities or watching how-to videos on YouTube. We live in a golden age, don’t we? I mean, sure, people will look back at our period of history and cringe quite a bit, but the idea that I can search just about any term, and find information about it on Wikipedia, and probably find a course on it by an actual college professor…. it’s just mind boggling. I’m lucky as it is, but I often think about if I was a kid growing up in this era. I’d be overwhelmed, sure, but I would totally be taking online courses left and right.

Actually, even if I weren’t a kid. I just googled the subject of that NYT article and found his twitter account. His most recent post is from 2016 but links to a YouTube series from UCLA on the history of India. I am TOTALLY watching that.