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Comment by fpgaminer | Hacker News Reader

Tangentially related. Whenever I get a new drive, I always do a "burn-in". A program writes data to the whole drive and then reads it back (reproducible random data).

Is there any real justification for doing this kind of test on a new drive?

Doing it takes quite awhile, so I've been wondering lately if it's even worth it. I've never found anything with it.

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In one of their first blog posts about the pods they stated that they saw 'high infant mortality' in drives so they would burn-in each pod for a few days before writing any customer data to one.

Thank you. Found the post: https://www.backblaze.com/blog/alas-poor-stephen-is-dead/

They have another good idea in there: recording the SMART data before and after the test. Their theory is that even if SMART attributes are still OK after the test, looking for a trend in the attributes may point to eventual failure later. Nice.

I do this with SD cards, I've found fakes with regards to speed and capacity. But I use ZFS for drives and just trust it to do its thing.

Yup, I do this with SD cards as well. To do this on the commandline, I just fill it up with big gigabyte-sized files. The loop uses "seq 1 16"; at least 15 files should fit on a 16 GB stick.

    $ cd /Volumes/your_new_SD_card
    $ dd if=/dev/urandom of=test.bin bs=10000000 count=1000
    $ for i in $(seq 1 16); do cp test.bin test$i.bin; done

For good measure, you could run md5/md5sum on the files.

If you've never found anything with it, why do you keep doing it (see: the definition of insanity)?

I have. Last time I bought a bunch of drives for a RAID array, I used the WD utility to test each of them. 1 of the 6 failed the test.

"Failed" as in "with an IO error" as in "got the wrong data back"?

Because if it's the latter, it could've been caused by some other part of IO stack and not necessarily the drive itself.

I believe the WD utility sends a command to the drive so it does a self test. That would eliminate any upper layers issues.

The first time I learned about burnin, it was because the drives for our RAID array showed up three days before we were supposed to start experimenting. Two of the ten were DOA. FED-EX got us replacements in two days. One of those was dead.

So then I started doing math on MTBF and lots of drives and things looked bleak. Just a couple years later MTBF had gone way up and continued to climb for a while after, but at that particular moment it was something like eight months between failure of you had any more drives than we had and just accelerated from there.

Not the parent, but probably because

1. It's notorious that hard drives have a higher failure rate at the beginning of their lives than in the middle (see bathtub curve [0]). So it's not absurd to test them hard early on before writing any useful data and to do an early RMA.

2. The failure rate on drives is low enough that his methodology may be right but he still never has any failure in his life. Doesn't it make insane.

[0] https://en.wikipedia.org/wiki/Bathtub_curve

It would depend on the effort to do the methodology vs. the expected return (savings of finding a failed drive times the probability).

I once bought a new 1TB Drive when they were fairly new. MOVED about 500gb if data to the new drive. Checked it. Seemed fine. Turned computer off and went to bed.

Next day the HDD didn’t turn on. Completely dead. :( I’ve never had a failure since but I backup everything now.

Why do you back up drives if you've never had a failure?

For the same reason you buy fire insurance even though your home has never burned down.

   insanity | inˈsanədē |
   noun
   the state of being seriously mentally ill; madness

I'm not sure when the definition of obsessive-compulsive started being used to describe insanity (it's been going on for at least a decade), but I don't like it (and cringe every time I hear someone repeat it).

Me too, one could argue that practicing anything is "doing the same thing over and over expecting different (getting better) results" ================================ I too have switched to HGST thanks to the backblaze stats.

This is a very strange invocation of the definition of insanity.

Apparently, quality assurance should never be a thing.

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