I am trying to test the linear stability solver in parallel. I did a simple test with the channel flow with a single processor and on 8 processors. I observed the following:

Time taken per 1000 steps for single processor = 2.76512s

Time taken per 1000 steps for 8 processors = 24.7811s

I expected a reduction in the computational time while running parallel. Is there any issue in the parallel implementation of the linear stability solver? Is something related with the eigenvalue solver?