Exit status 137 from mbtiles.go:63 while generating planet about sequentially-generate-planet-mbtiles HOT 1 CLOSED

I looked up a bit, this probably means, that the tilemaker container has been killed due to OOM. I think this project is genius, and we will definitely incorporate it in our operations. The ability to resume is a huge plus. Thanks for creating this! I would like to summarize my experience below, it may help take a step towards the stated goal of the project.

This program aims to be a simple set and forget, one liner which gives anyone - a way to get a full-featured and bang up to date set of vector tiles for the entire planet on small hardware.

So here it is: The auto ram setting decided it can take up to 5950 MB memory, so I have manually lowered that to 4096 MB, but still, I regularly saw memory consumption of the tilemaker process well over 5 GB. Fortunately I managed to add a 8 more GB of RAM to the instance (now total of 16 GB), so I managed to finish the process. I observed a max memory usage of 10.3 GB for an input size of ~190 MB (cut size was determined at 273 MB). That file contained over 43 million tiles, and I think that is reason for the memory requirements. I am wondering if it is possible to take into consideration the number of tiles in a slice, when determining if it requires further slicing.

There were also minor annoyances like when run without a pbf file given, and if there is an error, usually after the first re-run, the planet osm file is removed (considered corrupt for some reason), thus it needs to be downloaded (and possibly sliced) again. So I quickly reverted to a config file, and I downloaded the planet file myself (I got the url from the code). I also noticed that the shape files are always unzipped, seems unnecessary.

A good improvement would be if slicing could be continued from a previously complete state. So for example in my case, after slicing completed for the 5950 MB RAM limit, I had to rerun the whole process, but it would have been much more efficient to just continue with the already present slices.

Also there was an issue, that a journal file has been left in the mbtiles directory, and that caused tile-join to fail, so I had to rerun the whole joining again.

I am closing this issue, as it is not a bug, but I see several improvements here (I have never written a single line in go):

• drastically reduce the auto-determined memory limit. I would say 1/4 of detected memory could be OK
• or alternatively tile count could be taken into account during the decision if a chunk needs further slicing
• do not remove planet.osm.pbf automatically (when no pbf file is given), maybe prompt the user before doing so
• improve slicing so it can continue from a previous final state with a new bound (lower than before)
• ensure tile-join is only run on *.mbtiles files only, no journal file should be passed to the command

Please let me know what you think about these ideas!

from sequentially-generate-planet-mbtiles.