[Patch] Memory Error opening big OSM file

[marcoahp@…]

What steps will reproduce the problem?

1. Open a big OSM file, for example spain-latest.osm from geofabrik.de

What is the expected result?

Open the data

What happens instead?

Memory error.

Please provide any additional information below. Attach a screenshot if possible.

I've tested with -Xms2048m parameter but with the same result

URL:http://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2016-09-06 00:16:07 +0200 (Tue, 06 Sep 2016)
Build-Date:2016-09-05 22:21:00
Revision:10966
Relative:URL: ^/trunk

Identification: JOSM/1.5 (10966 es) Windows 10 64-Bit
Memory Usage: 247 MB / 247 MB (124 MB allocated, but free)
Java version: 1.8.0_111-b14, Oracle Corporation, Java HotSpot(TM) Client VM
Screen: \Display0 1920x1080
Maximum Screen Size: 1920x1080
VM arguments: [-Djava.security.manager, -Djava.security.policy=file:<java.home>\lib\security\javaws.policy, -DtrustProxy=true, -Djnlpx.home=<java.home>\bin, -Djnlpx.origFilenameArg=%UserProfile%\AppData\Local\Microsoft\Windows\INetCache\IE\IE1IG3IQ\josm.jnlp, -Djnlpx.remove=true, -Djava.util.Arrays.useLegacyMergeSort=true, -Djnlpx.splashport=60863, -Djnlpx.jvm=<java.home>\bin\javaw.exe, -Djnlpx.vmargs=LURqYXZhLnV0aWwuQXJyYXlzLnVzZUxlZ2FjeU1lcmdlU29ydD10cnVlAA==]

[GerdP]

You'll probably need far more memory (and a lot of patience) for such a large file. My experience is that JOSM can handle an osm.pbf file with 15 MB, but many actions might be very slow.

[bastiK]

We try to optimize the JOSM so that big extracts can be opened and edited. There has to be a limit somewhere and the Spain extract is much too big for 2 GB of memory. Please give more details if you think JOSM is wasting memory or you think it is a regression.

[GerdP]

Please review attached small patch.
I think either this should be used or remove the call of intern().

[GerdP]

Some numbers for a file with ~ 1.000.000 nodes:
The unpatched version allocates ~ 772 MiB (~995.000 StyleCache instances),
the patched version allocates ~ 335 MiB (351 StyleCache instances)

I think the code for StyleCache doesn't work since r9284.

[Don-vip]

In 11212/josm:

fix #13907 - StyleCache broken (regression from r9284, patch by Gerd Petermann)

[Don-vip]

In 11214/josm:

see #13907 - fix unit test

[bastiK]

In 11215/josm:

see #13907 - add unit test for problem fixed in [11212]

[bastiK]

Replying to Gerd Petermann <gpetermann_muenchen@…>:

Some numbers for a file with ~ 1.000.000 nodes:
The unpatched version allocates ~ 772 MiB (~995.000 StyleCache instances),
the patched version allocates ~ 335 MiB (351 StyleCache instances)

I think the code for StyleCache doesn't work since r9284.

Great find! A bit embarrassing not to notice this before ...