[split] GIMP crashes randomly

[Ofnuts]

I don't think fragmented memory is a problem, at least as long as everything fits in RAM. Your problem is possibly that Gimp starts overflowing its tile cache and starts using its own swap or makes your computer swap, and then you have disk I/O added to the picture. If you have a SSD this may not be too obvious (but will wear out the disk in the long run). If you have a HDD the slow-down is more noticeable.