Arnt Gulbrandsen
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2012-05-20

Linux, SCH, Crucial C300, and it works

I had replaced the Nokia Booklet, but somehow it replaced its replacement again. Something about its shape, about the keyboard. Whatever it is, the Booklet wants me to use it, and the replacement gathers dust. I'll try again when Apple releases retina macbooks, because 1GB RAM is really not enough.

The retima macbooks aren't here yet, so I tried to install Ubuntu 12.04 on the Nokia. It didn't work very well with the SSD I had installed. Apparently the Crucial C300 (or perhaps the Intel SCH controller) doesn't like a trim command of 1Mbyte or more, so the kernel reports a timeout during data set management, resets the drive, and from that point things don't work very well at all.

The only workaround is to boot into a live file system, open a console window, fdisk the disk (or do something else to make the kernel notice the disk), locate a file called /sys/…/scsi_disk/…/provisioning_mode, and write unmap into it. Then install linux as usual. Once you boot, write the same echo -n unmap > /sys/…/provisioning_mode command into /etc/rc.local so it's run at boot. I think the disabled provisioning mode would be more appropriate, but the kernel ignored me when I tried to set that, so…