Restoring performance and estimating life of a used SSD drive

maintenancessd

My old 128 GB SSD drive is about a year and a half old now, and I've since upgraded to another drive.

I'd like to clean up my the old SSD to …

  • restore its performance to near-new levels

  • rehabilitate it and generally give it a health check

How do I go about doing this?

Best Answer

On Linux, simply run

hdparm --trim-sector-ranges start:count /dev/sda

passing the block ranges you want to TRIM instead of start and count and the SSD device in place of /dev/sda. It has the advantage of being fast and not writing zeros on the drive. Rather, it simply sends TRIM commands to the SSD controller letting it know that you don't care about the data in those blocks and it can freely assume they are unused in its garbage collection algorithm.

You probably need to run this command as root. Since this command is extremely dangerous, as it can immediately cause major data loss, you also need to pass --please-destroy-my-drive argument to hdparm (I haven't added this to the command line to prevent accidental data loss caused by copy and paste.)

In the above command line, /dev/sda should be replaced with the SSD device you want to send TRIM commands to. start is the address of the first block (sector) to TRIM, and count is the number of blocks to mark as free from that starting address. You can pass multiple ranges to the command.

Having personally done it with hdparm v9.32 on Ubuntu 11.04 on my laptop with a 128GB Crucial RealSSD C300, I have to point out an issue: I was not able to pass the total number of disk blocks (0:250069680) as the range. I manually (essentially "binary searched" by hand) found a large enough value for block count that worked (40000) and was able to issue TRIM commands on a sequence of 40000 ranges to free up the entire disk. It's possible to do so with a simple shell script like this (tested on Ubuntu 11.04 under root):

 # fdisk -lu /dev/sda

 Disk /dev/sda: 128.0 GB, 128035676160 bytes
 255 heads, 63 sectors/track, 15566 cylinders, total 250069680 sectors
 ...

to erase the entire drive, take that total number of sectors and replace 250069680 in the following line with that number and run (add --please-destroy-my-drive):

 # i=0; while [ $i -lt 250069680 ]; do echo $i:40000; i=$(((i+40000))); done \
 | hdparm --trim-sector-ranges-stdin /dev/sda

And you're done! You can try reading the raw contents of the disk with hexedit /dev/sda before and after and verify that the drive has discarded the data.

Of course, even if you don't want to use Linux as the primary OS of the machine, you can leverage this trick by booting off a live CD and running it on the drive.

Related Question