Saturday, July 09, 2016

textareas slow in Chrome

So there’s a page on my site, https://www.doogal.co.uk/BatchGeocoding.php, that someone complained about. Specifically, they complained that if they tried to geocode 3,000 postcodes, it was terribly slow. I tried it myself and experienced the same problem. When geocoding postcodes, the page uses my own internal database, so it should suffer none of the throttling issues of Google Maps. No worries I thought, I can reproduce the problem, which is generally the biggest hurdle, fixing it should be straightforward.

So I fired up Chrome’s profiler and found… absolutely nothing… None of the delays were in my code. So I tried Microsoft Edge and it was super quick. I pretty much gave up at that point and suggested the user tried MS Edge.

Three weeks later I had a look with fresh eyes. And something popped up from the recesses of my mind, spellcheck=”false”. I vaguely remembered setting that attribute on a textarea in the past had improved performance and once again, this fixed the issue. A single geocode was previously taking a second, now all 3,000 took a couple of minutes. This may be a bug in Chrome or maybe spellchecking is a very CPU intensive process. Either way, turning it off makes everything better.

As always this is just a reminder for me and maybe it will be useful to someone passing through.

Friday, July 01, 2016

Property sales data for May 2016

I’ve uploaded the latest Land Registry data to my site. Every month I say the same thing and I will do so again. Prices continue to rise at a steady pace…

Tuesday, May 31, 2016

Land Registry sales data for April 2016

I’ve uploaded the latest Land Registry data to my site (although the postcode level summary data is still being generated). The annual change has dropped to 1%, which may well be the first effects of the BTL tax changes recently introduced.

Wednesday, May 25, 2016

UK postcode data for May 2016

I’ve uploaded the latest UK postcode data to my website. Well, nearly all of it. Northern Irish postcodes are still from 2008 since the nice folk at NISRA still release their data under a restrictive license. I assumed at some point they would come into line with the rest of the UK and provide the postcode data with a liberal license, but it doesn’t seem to be happening. Since the data I have is now very old (from a time when the data was released with a liberal license), I am considering removing it from the site. Let me know if you find it useful and I’ll keep it online. And maybe send a polite request to NISRA to open up their data…

Sunday, April 24, 2016

doogal.co.uk now using https

For a while now, Google has been trying to get everyone to move their sites over to https. There’s lots of valid reasons to do this, although the majority of sites don’t really need it.

The carrot of improved rankings hadn’t prompted me to make the change but Chrome 50 removed support for geolocation services which I use in a number of places. So the site was broken in Chrome 50. And it was that stick that motivated me to make the switch.

One reason I’d held off from using https was the cost of a certificate. But things have moved on and it’s now possible to grab a certificate for nothing from Let’s Encrypt. It’s pretty simple to acquire and install a certificate using these instructions

So the switch has been made. For most users of the site, nothing should have changed, unless I’ve broken something (let me know!). Comments are currently being migrated, so you may find some comments aren’t where they should be. If you are grabbing data from the site directly you may need to change the URL you use from http:// to https://. 

Sunday, April 10, 2016

Sampling Strava again

I thought I’d repeat the experiment conducted by Mark Slavonia last year to see how the Strava usage numbers stack up now.

First I needed to know the number of signed up users of Strava. This is pretty straightforward, head off to https://www.strava.com/athletes/6161562 and keep increasing the number at the end until Strava says it can’t find a user. Last March there were 8.2 million users, now there are about 14.4 million, not a bad increase for just over a year.

Next I wanted to capture the active users and the premium users. Since I’m a techy, I can automate this process using the Strava API and a .NET wrapper around it. So I decided to sample 1 in every 10,000 users, giving me about 1,440 sample users which should give the results a reasonable accuracy.

After pulling down that data, the first thing I noticed was that 47 of my requests had returned ‘Not Found’ errors. In fact, most of these were grouped together, suggesting Strava decided to restart their numbering with larger IDs at some point. So the total number of users is probably just shy of 14 million.

Premium Users

Of the 1.393 users I had left, 28 were Premium users, so approximately 2% of all users. This figure is pretty close to last year’s figure so I’m happy to believe it. That equates to 280,000 premium users or $16.6 million in revenue for Strava.

As an aside, I’m a Premium member, but not because Strava offers particularly compelling features for Premium users, but mainly to show my support for a website that is exceedingly useful and fun. I suspect Strava could differentiate between free and Premium a lot more to increase the percentage of Premium users. Take a look at all the functionality available at veloviewer.com.

Active Users

The Strava API doesn’t let me get activity data for other users, so I’m not able to find out how active users are directly. But it does provide an Updated field, which I’m hoping gets updated when a user uploads an activity (the Strava API docs are a little vague on this point). Using last year’s definition of an active user being someone who has done something in the last 24 days, how many active users are there? I found 181 users where that Updated field was in the last 24 days. That’s about 13%, or 1.8 million active users. The percentage is again fairly close to last year’s figure so I’m happy to go with it.

Gender

I found 806 men and 270 women and 317 blanks. Ignoring the blanks, that almost exactly a 75% / 25% split between men and women.

By Country

I think my sample is too small to draw accurate conclusions from the home countries of Strava users, but lets play with the numbers anyway. 463 had blank entries for the country which leaves 930 users with a country specified. I’ve removed countries with less than 5 users in my sample and then adjusted for population. Below I’ve highlighted the countries where more than 2% of the population have signed up for Strava. It seems like there is massive potential to increase usage in many countries, although that may depend on whether there is a culture of recreational running and riding in these countries (China and India being the obvious biggest potential markets). And little old blighty, the UK, is top of the pile. Go UK!

Country Population Sampled users Approximate Strava users % of population
Australia 24,309,330 35 527,000 2.2
Austria 8,569,633 5 75,000 0.9
Belgium 11,371,928 6 90,000 0.8
Brazil 209,567,920 74 1,114,000 0.5
Canada 36,286,378 25 376,000 1.0
Chile 18,131,850 6 90,000 0.5
Colombia 48,654,392 9 135,000 0.3
Denmark 5,690,750 5 75,000 1.3
France 64,668,129 35 527,000 0.8
Germany 80,682,351 18 271,000 0.3
India 1,326,801,576 5 75,000 0.0
Ireland 4,713,993 9 135,000 2.9
Italy 59,801,004 37 557,000 0.9
Japan 126,323,715 9 135,000 0.1
Mexico 128,632,004 6 90,000 0.0
Netherlands 16,979,729 32 482,000 2.8
New Zealand 4,565,185 9 135,000 3.0
Philippines 102,250,133 8 120,000 0.1
Poland 38,593,161 5 75,000 0.2
Portugal 10,304,434 16 241,000 2.3
Romania 19,372,734 6 90,000 0.5
Russia 143,439,832 12 181,000 0.1
South Africa 54,978,907 16 241,000 0.4
South Korea 50,503,933 14 211,000 0.4
Spain 46,064,604 46 692,000 1.5
Switzerland 8,379,477 7 105,000 1.3
Taiwan 23,395,600 14 211,000 0.9
Ukraine 44,624,373 6 90,000 0.2
UK 65,111,143 153 2,303,000 3.5
US 324,118,787 233 3,508,000 1.1