No answer, but more details will perhaps help get more suggestions.
Which version of linux ? Which sub-version of Gimp (use Help -> About)
12 GB of memory should be more than adequate but how much free disk space is available ?
How big in memory (see bottom of Gimp window) is this 50 layer image ? and image size in pixels (see top of Gimp window)
Which version of linux ? Which sub-version of Gimp (use Help -> About)
12 GB of memory should be more than adequate but how much free disk space is available ?
How big in memory (see bottom of Gimp window) is this 50 layer image ? and image size in pixels (see top of Gimp window)