On Mon, 2010-06-14 at 14:24 -0500, Michael Cronenworth wrote: > John Austin wrote: > > 3. Does setting the "discard" option do everything that is required to enable > > TRIM to do its job with no further action? > > Yes. > > > > > 4. Is it safe to use the "discard" option yet? > > I am using ext4 on /boot. btrfs on /. No issues with /boot or /. There > were a few mailings[1] about performance issues with btrfs, but I have > not seen any negative effects in normal desktop usage. > > [1] http://www.mail-archive.com/linux-btrfs@xxxxxxxxxxxxxxx/msg03443.html Hi All Many thanks for the replies I think I have taken them all on board However I have failed to properly sort out the "hotplug" options so far ! Still working on it. My SSD (which dangles on an eSATAp cable) is used in two modes 1. As a "fixed" F13 test disk (ext4 partition) (Mode 1) 2. As a "hot-pluggable" backup disk (Mode 2) It has 3 partitions as follows (to achieve alignment) (fdisk) Disk /dev/sdb: 128.0 GB, 128035676160 bytes 224 heads, 56 sectors/track, 19935 cylinders Units = cylinders of 12544 * 512 = 6422528 bytes Disk identifier: 0xfc656088 Device Boot Start End Blocks Id System /dev/sdb1 5 20 100352 83 Linux /dev/sdb2 21 6400 40015360 83 Linux /dev/sdb3 6401 19932 84872704 83 Linux -------------------------- (parted) unit cyl (parted) p Model: ATA C300-CTFDDAC128M (scsi) Disk /dev/sdb: 19935cyl Sector size (logical/physical): 512B/512B BIOS cylinder,head,sector geometry: 19935,224,56. Each cylinder is 6423kB. Partition Table: msdos Number Start End Size Type File system Flags 1 4cyl 19cyl 16cyl primary ext3 2 20cyl 6399cyl 6380cyl primary ext4 3 6400cyl 19931cyl 13532cyl primary ext3 ------------------------------------------------------------- In Mode 1 the scheduler is set by a script at boot time Effectively it does echo noop > /sys/block/sdb/queue/scheduler the device (sdb shown) is sorted out using blkid ------------------------------------------------------------- In Mode 1 the noatime and discard options are set in fstab [root@naxos ~]# cat /etc/fstab ... UUID=f02d542f-2ad4-487f-bda2-d3135c404c78 / ext4 defaults,noatime,discard 1 1 ############################################################# Currently in Mode 2 I have a script that has to be run as root to set the scheduler and options as above after the SSD is plugged in. To my knowledge I have had no problems with the discard option. Regards John -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines