I get very strange and disturbing performance results for Import-Csv cmdlet.

Import 111 Mb csv log file:

• On Windows PowerShell always ~ 3.7 sec. Memory ~ 10 Mb.
  -On PowerShell Core from 6 sec up to 27 sec - each subsequent launch increases the time by 1-2-3 seconds. Memory grow from 1 Mb to 105 Mb. After waiting some minutes memory decreases to ~1 MB and agaim the cmdlet take ~6 sec.

I suppose we get the same for any script.