Been a long field season this year, which has kept me away from this site. Not over yet – still have one more session left, running through the end of next week. Then I’ll be back home, and hope to get this site cranking again soon.
Archive for the 'blogkeeping' Category
Back in the field for the next few weeks; posting should resume after Memorial Day.
After my previous two posts on Android, you might expect to see posts on Android-related topics showing up here at Free Geography Tools. That was my original plan, but I’ve decided that Android is a distinct-enough topic to warrant its own website. So, I’m announcing my new Android-specific website, going online today (8/18/10): AndroGeoid. There, I’ll cover apps and topics related to using Android hardware and software to explore, measure, record and map the world. This will include obvious geography-related topics, like apps for :
- Map displays
- And so on …
But the website’s focus will range well beyond that, to topics that encompass some of Android’s more unique capabilities;
- Geographically-related Augmented Reality
- Location-linked online information resources
- Crowd-sourced data collection
- Measurement apps that take advantage of Android’s sensor suite (accelerometers, orientation, magnetic field)
- Applications for recording full sets of information linked to location: Coordinates, direction, orientation, notes, photos, videos, sound, panoramas, augmented/virtual reality, and more.
- And other cool stuff …
The Android world is currently dominated by smartphones, connected wirelessly via 3G to the Internet, and I’ll cover apps that take advantage of that. But the ecosystem is likely to expand very soon to models that only come with WiFi connections, and even with smartphones there will be times when no connectivity is available. So, I’ll also cover apps that work with non-connected stand-alone Android devices.
And the name, AndroGeoid? Well, GeoAndroid was already taken ;-). But AndroGeoid works for me: the geoid is:
that equipotential surface which would coincide exactly with the mean ocean surface of the Earth, if the oceans were in equilibrium, at rest, and extended through the continents …
The first couple of posts may look familiar – they’ll be slightly revised versions of the posts I’ve done this week on Android. New material should start showing up on Friday. Plus, I’ll have a brief weekly listing/recap of AndroGeoid posts on this site, usually on Fridays.
And in case you were wondering, I still expect to post regularly on the Free Geography Tools site at about the same frequency as I have been, about 4 posts a week. Hopefully, I can keep both sites up and running at the same time. Not unrelated, I’ve got a new Guest Post page up ;-).
In addition to the Internet connectivity issues I had earlier this month, I got zapped by a major website issue. My hosting service claimed that my WordPress blog had a problem either with its mySQL databases, or with malformed queries that resulted in an abnormally-heavy server load. They said it was so bad that they had to shut down my account completely for about 4 hours on December 23rd to keep the server running. I took a look at the queries, and didn’t see any problems with them, and a brief inspection of the mySQL databases didn’t show anything wrong. But to make sure that was the case, and to keep my hosting company happy, I took a deeper look at my blog to see if there was anything I could do to remove any cruft that had built up in my blogfiles since I switched to WordPress in June 2007. This isn’t exactly geography-related, but I thought that some WordPress users might find a description of what I did useful.
1. First, I de-activated unneeded plugins. I’ve tried numerous plugins in the year-and-a-half since switching to WordPress, and had pretty much already settled on a core group of eight useful plugins. But there were a couple that weren’t completely necessary anymore, and de-activating them was likely to lessen the server load.
2. Next, I backed up the mySQL databases before trying to work with them, in case something got screwed up. Many hosting companies offer access to control panels like phpMyAdmin that lets you do this. But if you don’t have this access, or if it’s too complicated, there’s a free WordPress plugin called WP-DBManager that lets you create DB backups from the WordPress dashboard, and restore them if necessary (along with some other useful functions).
3. When a WordPress site loads, it reads the wp_options database for configuration data for both the basic site, and plugins. There should be no more than a few hundred entries in this table at most, and the bigger it gets, the longer a site takes to load. Here’s the story of one site owner who discovered that there were over 19000 entries in this table, most of them unnecessary RSS hashes; another source of unneeded entries are from plugins that created them when installed, but didn’t remove them when de-activated. There’s a plugin called Clean Options that does a good job of finding most unneeded options entries based on whether there are any active plugins that use them. Running this plugin reduced the number of wp_options entries on my site from 355 to about 250. But it also found an erroneous blank entry, but didn’t offer a way to remove it. Once you’re finished with this plug-in, it’s OK to deactivate it until you need it again.
4. Going into phpMyAdmin and manually browsing the wp_options table, I found and deleted the blank entry. But there were also about 50 additional table entries for deleted plugins that Clean Options hadn’t found, so those were deleted as well.
5. The wp_posts table contains individual entries for all the posts, pages and images on the blog. The total number of entries was 2700, which seemed high since there’s fewer than 600 posts on this blog to date. An examination of the entries by title showed why – there were numerous duplicated title entries for many of the posts. A bit of research turned up the reason. WordPress 2.6 introduced post versioning, which seemed like a good idea to me. But with every revision to a blog post, even a minor tweak, a new database entry was created for that revision. This was making the wp_posts database table grow a lot bigger than it really needed to be.
WordPress knows about this, but decided that the feature was so useful, and the overhead associated with the larger table so minimal, that they didn’t include the option to turn off versioning, nor to delete unneeded versions. Fortunately, there’s a plugin called Disable Revisions that not only disables revision versioning, but deletes all the revision entries in the wp_posts and wp_postmeta tables. Make sure you backup your database first before activating the plugin, as it does the deletion as soon as it’s activated. Installing and running this plugin decreased the table size by about a third, from around 2700 entries to roughly 1800.
6. I also found a number of database tables created by plugins that were no longer present, and dropped those. The default WordPress installation only has 10 database tables:
Any other tables were most likely created by plugins. Usually the name is enough to let you figure out which plugin created it, but if not, just Google the table name. If it was created by a plugin that’s no longer installed, you can probably drop it (but always backup first).
7. I then checked and optimized the database tables using phpMyAdmin; the WP-DBManager plugin can do that as well.
8. Finally, I found useful suggestions at this site and this one for speeding up page loading. For example, in the WordPress theme header and footer sections, php code is used to insert web addresses for style sheets, RSS feeds and coding. But these addresses are normally static, and you can speed up the loading process by replacing the php code that pulls up the address with just the address text itself. For example, the original code for specifying the CSS sheet for this blog was:
<link rel=”stylesheet” type=”text/css” media=”screen” href=”<?php bloginfo(‘stylesheet_url’); ?>” />
By opening my blog’s home page, and using the View => Page Source option, I found that the stylesheet’s static URL was
Replacing the php code with this static URL, I get:
<link rel=”stylesheet” type=”text/css” media=”screen” href=”http://freegeographytools.com/wp-content/themes/K2/style.css” />
Because the php code doesn’t have to be interpreted to retrieve the URL, the page loads a bit faster for every case where you can do this. I also dropped several unneeded lines of this type, such as the one that retrieves the WordPress version number and inserts it into a meta tag. Getting rid of this not only speedsup page loading, but improves your site’s security. If a security flaw is found in a particular version of WordPress, the version meta tag can tell an intruder instantly whether your site is vulnerable. If the tag is missing, it’s not as obvious whether your site still has this vulnerability or not.
Did all this solve my site problems? Don’t know yet; I’m getting fewer mysql_slow_query log entries, but haven’t gotten rid of them entirely. But I suspect that’s a server-related issue, which I can’t do anything about. I can say that my blog pages load in about half the time they used to in Firefox, and a third of the time in Internet Explorer, so presumably that reflects a reduction in my site’s load on the server.
Hopefully now I’m done with all these issues, and can get back to geographically-oriented posts on a more-normal schedule.
Slightly, but not completely, off-topic: I used to subscribe to the feeds for Engadget and Gizmodo, two blogs devoted to the latest and greatest in high-tech gizmos. But I dropped those feeds because:
- I was getting inundated with dozens of posts every day, most on items I had no interest in
- Too much “gadget porn”: drooling and obsessing over the latest and greatest in gimmickry without asking the questions, “Do we really need this?”, and “Is it really worth it?”
So now I’m down to one gadget blog, and the one I highly recommend: Cool Tools from Kevin Kelly, one of the creators of Wired Magazine. Why do I like it?
- Usually no more than one post a day.
- Talks about tools that actually do something useful or interesting.
- Not just the latest and greatest, but brings existing but obscure tools to your attention.
- Posts are thorough and thoughtful reviews, not just rehashed publicity releases.
- Not just computers or electronics, but a wide variety of topics: Aural, Autonomous Motion, Backpacking, Big Systems, Clothing, Communications, Community,Computers, Consumptivity, Craft, Culture, Design, Destinations, Dwelling, Edibles, Family, Gardens, General Purpose Tools, Health, Homestead, Inner Space, Kitchen, Learning, Life on Earth, Livelihood, Living on the Road, Materials, Media Tools, Paper World, Photography, Play, Science Method, Somatics, Source Wanted, Tips, Vehicles, Visual Media, Workplace. It’s fun just browsing through the different categories to see what you’ll stumble upon. No geography-related categories, but a search for “maps” or”GPS” will bring up a bunch of posts.
Give Cool Tools a look; I think you’ll like it.
I’m also keeping my eye on a newcomer, BoingBoing Gadgets; perhaps a bit too techy for my tastes, but does branch out beyond the standard electronics stuff.
Over the years, I’ve been stumbling across a fair number of free (or cheap) geographical information tools for GIS and GPS applications. These range from full-blown GIS apps to simple utilities, and websites with both data and data services. Some of these are fairly well-known, others less so, and I’ve gotten a lot of good use out of them. Now I’ve decided to start regurgitating some of what I’ve picked up over the years, and start posting reviews, information and how-tos on this blog about where to get these tools, what they can do, and (sometimes) specific examples of how to use them.
While the websites will be OS-independent, the software I’ll be talking about will most often run only on Windows XP (though I’ll try to note if there are versions for other OSes as well). I’m not an OS snob, and if I were I wouldn’t be running Windows XP. But there are good reasons for concentrating on Windows applications:
- I have a Windows XP machine (several of them)
- I don’t have a Mac (but am willing to accept any donations).
- Every few years, I install the latest and hottest version of Linux on one of my systems, to see if it’s really ready to be my main desktop system; so far, the answer has been no. Ubuntu is getting close, though …
- There’s far more software available for Windows than there is for Mac and Linux; that’s not a comment on the quality of the OSes, just a fact of life.
Finally, some of the programs will be FOSS (free and open source), but a lot of them won’t be. If a program does a good job, I’m not going to discriminate against it just because it isn’t ideologically pure, especially if it doesn’t cost anything.
I welcome any and all comments, suggestions, recommendations, etc.. In particular, if there’s some GIS/GPS task that you’ve been looking for a solution for, let me know; I may know just what you’re looking for.