As suggested by apw, I booted the system with "enable_mtrr_cleanup" and "mtrr_cleanup_debug", and the system performance was normal. Attached the dmesg.
** Attachment added: "dmesg_2G_mtrr_cleanup.txt" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/816035/+attachment/2233987/+files/dmesg_2G_mtrr_cleanup.txt -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/816035 Title: Memory upgrade makes Ubuntu painfully slow To manage notifications about this bug go to: https://bugs.launchpad.net/null/+bug/816035/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
