I’m working on a laravel app that connects to a R server via Rserve (using ctuberlin/rserve). The app is in a docker container and the R process is running on a separate container. Link to GitHub here.

The app allows us to make tasks and exercises in R that are corrected automatically. The problem is we have to limit resources for each user session so that faulty student code doesn’t take out the whole docker container.

We are using unix::rlimit_as(1e9) as a memory limit.

Problem is, whenever the exercise requires some library, the library() call hits an error.

Example of errors:

r_1      | Error: package or namespace load failed for ‘png’ in dyn.load(file, DLLpath = DLLpath, ...):
r_1      |  unable to load shared object '/usr/lib/R/site-library/png/libs/png.so':
r_1      |   /usr/lib/R/site-library/png/libs/png.so: failed to map segment from shared object

Or testing manually inside the container (with docker exec):

> unix::rlimit_as(1e9)
$cur
[1] 1e+09

$max
[1] Inf

> library(RMySQL)
Loading required package: DBI
Error: package or namespace load failed for ‘DBI’:
 memory exhausted
Error: package ‘DBI’ could not be loaded

Removing the rlimit call or moving it to after the library call avoids this error.

I don’t understand why this is happening, since if I run the exact same commands on my local system, it works fine. It could be an issue with the container configuration? I’m at a loss as to how to troubleshoot this.

Links to my R container Dockerfile and docker-compose.yml.