New simultaneous viewers record and related slowness

Seems like we hit a new high of over 1000 simultaneous map viewers today, mostly thanks to Dayton Hamfest, and a popular live Hamfest video feed with an embedded map. They're giving away freebies.

A couple of components started hitting file descriptor limits, which had last been upgraded over a year ago. Too many simultaneous connections per process. This made the site perform very, very slowly. I quadrupled the limits, and the site started to perform quickly again, I hope that's enough for more than a year to come. Well, I have to admit that it would actually be a nice surprise if the site would be so popular that it wouldn't be enough...

I also fixed a bug in the "first heard" algorithm pointed out by Ian, VK1IAN. The digipeater alias GATE was not treated as a special digipeater alias (like WIDE, RELAY and TRACE are), and an igate which first heard a packet with a GATE in the digi path was not given credit for hearing it first.

Another fix that went in was a filter which takes out complete APRS packets which have somehow made their way to the comment field of another APRS packet. Apparently something is loosing CR LF sequences between packets (could be my code...), which causes packets to go into the comment of the previous one. Before I find the actual bug I've added a filter to strip these off.

Dayton Hamvention APRS view

Dayton Hamvention is here again on next weekend. I've set up a separate page showing live APRS activity at Hamvention.

Bob Bruninga is expecting to have APRStt running there, too, so if you're visiting Hamvention, you might be able to place yourself on the map using just a DTMF-capable 2m transceiver.

I've also added a new parameter 'he_maptype' in the APRS map embedding interface which allows you to select satellite, physical or hybrid map views in addition to the normal street map.

Date range with weather and telemetry lookup

I'm on a 2-week sick leave (my gallbladder was removed last week), and have some spare time for enhancements and bug fixes. Rest of the time I'm entertaining Armi the cat, who joined us on Friday.

This morning I added arbitrary date range lookups to the weather and telemetry pages. It allows you to look up a detailed graph between any two dates or times. It also has a little calendar widget for your convenience.

I've also done some XHTML validity fixes for better browser compatibility, switched to a smaller position marker on the static maps, and added some navigation links in the bottom of most pages. I also fixed the bug of date selection menu not appearing when clicking on 'start tracking' on the live map.

Also, the /info/ page of a weather station now shows a brief 'latest weather' report instead of the number of weather reports in database. It's probably much more interesting, and it's much quicker to load, too, since it's almost always cached in memory and doesn't require a potentially large disk read.

Google Maps loading problem fixed

Google released Google Maps API version 2.151 today, which somehow broke map loading for many users (including myself). I received a number of complaints that the map doesn't load. The Firefox error console gave the error "window.jstiming is undefined".

I've now manually downgraded to Google Maps API version 2.150 which seems to work better.

Sorry for the trouble, and thank you for your patience!

Some database cleanups

Since the popularity of the site is increasing I need to do some optimizations to keep the site running smoothly.

As announced before, I ran some database restructuring batch jobs during the weekend. The last one was actually started on Monday morning and the execution was completed early Tuesday morning. I hope the slowdowns were not too noticeable, I tried to make them run slowly enough to not interfere with normal use.

I'm currently looking at ways to clean up some unused data from the aprs.fi database. There's quite a lot of automatically or erroneously generated targets stored in the database, most of which are not really looked at by anyone. They just inflate my tables and make the prefix browsing view very cluttered. The performance impact caused by the extra targets isn't really noticeable, but it's just not very nice to have them there.

If you're keeping an eye on the statistics, you might have noticed that today I deleted about 60000 targets. Those were all APRS objects, which had only a single point stored (non-moving), which were last announced over a week ago, and which were announced for less than 12 hours. Almost all of them were automatically generated earthquake and severe weather warning objects, which don't really need to be here any more.

There's also an awful lot of regular APRS targets which have a corrupted source callsign. Most usually one or two characters have been lost from the beginning of the callsign. For example: 1VAJ (J41VAJ), 3GXT-2 (W3GXT-2) and 3TVX-9 (VE3TVX-9). You can find these by looking at the prefix browsing view, picking a strange prefix starting with a number, and looking up the correct original call in the "nearby stations" list of the info page. I wonder how the callsigns get mangled like this, and how could I remove these from the database without accidentally removing some valid data.

Slowdowns caused by maintenance work

I'm doing some changes in the database structures during this Friday evening and Saturday morning, so there might be some slowdowns in the aprs.fi service. In particular, updated data might take a few minutes to be inserted in the database. No data should be lost, though, it'll just be delayed. Thank you for your patience!

APRS in русский язык

Thanks to UZ2HZ, RA1AMW, UA3IRS and UR7IMM, aprs.fi is now available in the Russian language! The site has now been translated to 20 languages. Although there's not so much APRS activity in Russia yet, Russian is the primary language of about 164 million people living in quite a few countries. Even here in Helsinki, it's the third most common language.

There are spots of APRS coverage in (at least) St. Petersburg, Moscow and Novgorod.