Hi, provide my study here :-) As far as I can see to support TRIM via USB bridge the USB bridge chip MUST support SCSI / ATA Translation(SAT)'s ATA PASS THROUGH command in order to pass the TRIM command to the disk.
Reading drive's S.M.A.R.T. data is similar to TRIM which they both require working ATA PASS THROUGH command, you may checkout following webpages for more info: * [USB – smartmontools](https://www.smartmontools.org/wiki/USB) * [Supported_USB-Devices – smartmontools](https://www.smartmontools.org/wiki/Supported_USB-Devices) and YES, external HDD closure's controller may not provide this functionality, make sure to checkout the chip's datasheet before purchasing any new one(while some may support this functionality via controller firmware upgrade most of them don't) However even you can read S.M.A.R.T. data using smartmontools utility, TRIM is still (currently) not possible for unknown reason, might be the usb-storage kernel module issue I guess. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1336541 Title: No TRIM via USB To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1336541/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
