Don't forget that Gmail also started with a "measley" 1 GB, and has
grown over time. Don't be too surprised if the free storage quota of
App Engine grows over time, too.
Make me wonder, is the requirement for indexes and logs lower
for GMail then an average GAE app? Why is that so?
(very hypothetically speaking)
Colliberty Easy Publisher
Good question. I am not sure, but I think the answer is that yes, I need that.
Each points represents an altitude (from the NASA SRTM elevation data
of the whole world). My application displays an altitude profile of a
route. Let's say routes are typically between 1 km (walking) and 100
km (driving) and the altitude profile consists of 100 points (good
enough for mobile phone display). The elevation data resolution is 100
In that case the typical distance between the queried points is
between 100 (less makes no sense) and 1000 meters, or 1 and 10 data
points. So if I want to grab even just 2 points in one query, that
query would probably take another +- Pi * 10^2 points with it.
In other words, from the point of view of the database, the points
that I query are random and far between, so there is no point in
I am still not sure if that 95% indeed belongs to the entity key, or
if the key is already subtracted from my usage. But I hope you are
> P.S. Sjors, I suspect NASA SRTM comes in raster form, you could
> probably tile this data and store the smaller raster a packed arrays
> in the Blob type. Type array.array().tostring() This will give you
> good space efficiency since you can store the Short Ints in only 2
I am thinking that, in the current situation, the most efficient way
to store the SRTM data is in a file (or multiple files), in stead of
in the data store.
The most important thing is that I need to minimize disk reads so that
I only grab the 2 bytes that I need. My guess is that excludes .tar.gz
compression. That is a pity because this data just screams for
But I would much rather use the data store, for the sake of elegance.
Thanks for your suggestion! You can see my prototype app in action at:
And I wrote a post about the current issues: