Occasionally, many errors appear in the MCE log, /var/log/mcelog. For example:
CPU 0 BANK 9 MCG status: MCi status: Error enabled MCA: MEMORY CONTROLLER GEN_CHANNELunspecified_ERR Transaction: Generic undefined request STATUS 900000400009008f MCGSTATUS 0
If this is a one-time or an occasional event, you can ignore it. It should not impact performance.
If the errors persist contact Oracle Services for further review. Open a support case with Oracle Services and reference (Doc ID #1459158.1) for further analysis and evaluation.