No Caching Mode Page Found message for internal hard drive mount point.

English Install/Boot/Login
1

I’ve seen several posts regarding this message and usb drives. In my case, when I boot from my internal hard drive with an external usb drive plugged in, I do get this message but it references [sda] which is the device identifier for my internal hard drive. When I boot without the the usb drive plugged in I do not get the error message. I’m concerned that when I boot with the usb drive plugged in, I also get the “[sda] Assuming drive cache: write through” message. Again, sda is my internal hard drive. My concern is that the system is disabling the drive cache on the internal drive and thus slowing down the system. Is this true? Do I need to make sure the usb drive is unplugged when I boot?

A related issue, is that I also receive the IOMMU not enabled error message. I can enable IOMMU in the BIOS and eliminate the message. Is that recommended? I do run a Windows 7 VM about once a month or so, but it works ok without IOMMU. Is there some relationship between IOMMU and my NVIDIA graphics card? I can’t seem to find a decent explanation of the whole IOMMU issue, especially as to whether enabling it degrades normal system performance.

Thanks for any help.

2

The sdX can change according to what you have plugged and how the BIOS/UEFI is configured. That is why UUID is used for mounting things since sdX can be different between boots

3

Thanks for the response. My hard drive consistently comes up as sda. The usb drive does vary depending on what I have plugged in. Nevertheless, the message always refers to sda. That’s why I’m concerned.