I have a 14 page document with many in-line LibreOffice Math equations and anchored images from LibreOffice Draw. When I edit an equation by clicking on it the screen realigns to make room for the element view on the left side. This takes several seconds with fragments of the other views visible. Then the LibreOffice screen becomes grey for a few seconds. A similar sequence happens in reverse when I close the equation editor. Inserting new equations is equally slow.
This problem only recently started (July 2016). Prior to that the document did not slow down while editing equations.
I have gradually increased the memory allocated to LibreOffice in Tools/Options/Memory to 900 MBs with no change in performance. I have also used the System Monitor to watch the CPU activity during an equation edit. In each case one of the CPUs peaks at 100%. I am running Ubuntu 16.04 LTS with 7.7 GiB of memory and and Intel Core i&-377OS CPU @ 3.10 GHz x 8 with a 64-bit OS and 1.0 TB of disk space. I changed to LibreOffice on Linux last year and would appreciate any assistance. Thanks!