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Backblaze Hard Drive Stats for 2018

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21–30 of 165 posts

Re: Backblaze Hard Drive Stats for 2018

#21

Anything interesting in this one? I've stopped reading them because they all seem to be "Seagates fail kind of a lot but we use them because reasons. HGST doesn't fail a lot, but we also have statistically insignificant numbers of them, so ."

"because reasons" is an overly negative way to say "because they offer the best value"

They can get large numbers of them cheap, and their system is good at detecting and replacing bad drives, so why not use them?

Re: Backblaze Hard Drive Stats for 2018

#23

Anything interesting in this one? I've stopped reading them because they all seem to be "Seagates fail kind of a lot but we use them because reasons. HGST doesn't fail a lot, but we also have statistically insignificant numbers of them, so ."

With two categories A and B you don't need the same number in each category to compare whether they come from the same distribution.

I would be surprised if the number of drives they have is actually "statistically insignificant" \* but I haven't crunched the numbers.

https://en.wikipedia.org/wiki/Pearson%27s_chi-squared_test

\* By this I guess you mean that the null hypothesis of "they have the same failure rate" is not rejected.

Re: Backblaze Hard Drive Stats for 2018

#24
I realize my comment is a tangent. I'm hoping folks might be understanding and hopefully have some advice.

If you have terabytes to back up, are there still any backup services left that'll let you ship them a drive for a faster initial backup?

Re: Backblaze Hard Drive Stats for 2018

#25

Anything interesting in this one? I've stopped reading them because they all seem to be "Seagates fail kind of a lot but we use them because reasons. HGST doesn't fail a lot, but we also have statistically insignificant numbers of them, so ."

> HGST doesn't fail a lot, but we also have statistically insignificant numbers of them, so ."

They have over 20 thousand HGST drives now, according to this year's report, which seems significant to me.

They continue to have lower failure rates than the Seagates.

Re: Backblaze Hard Drive Stats for 2018

#26

Anything interesting in this one? I've stopped reading them because they all seem to be "Seagates fail kind of a lot but we use them because reasons. HGST doesn't fail a lot, but we also have statistically insignificant numbers of them, so ."

If I had to guess, the seagates are sufficiently cheap in ridiculous quantities, and Backblaze's multi-pod redundancy/parity and drive monitoring is good enough, that even if they have a 3% failure rate and the HGSTs have a 0.75% failure rate, that it's still an acceptable risk for them.

If you're an individual person with a 12-drive ZFS RAIDZ2 with hotspare, in a file server in your garage or something, you might prefer to pay the premium to buy HGST, because what if you have a double drive failure during a three week period while you're on vacation out of the country?

Re: Backblaze Hard Drive Stats for 2018

#27
post #13

Earlier quoted context omitted.

They're not going to be skewed. HGST disks are usually more expensive, so that limits the quantity that they buy. The seagate disks are usually cheaper but have a slightly higher (except when it's a brand new line) failure rate. When filling out a single server I go with the HGST disks because the premium price and quality means fewer failures, but it's more cost effective to go for lots of seagate disks when you hav…

I built a server a few years ago, and I determined it was more cost effective for a drive to fail than to use HGST. It would be more inconvenient, but having a drive fail on a home server with only 6 drives didn't seem very likely anyway.

If you have a 2%/year failure rate per drive, then that leaves you with a nearly 12%/year chance that at least 1 of 6 drives will fail each year. Or a 31% chance that at least 1 of 6 drives will fail within 3 years. Or a 52% chance that at least 1 of 6 drives will fail within 6 years.

Re: Backblaze Hard Drive Stats for 2018

#29

I'm interested in failure rate per iops. If the drive fails infrequently, great, but if it's also the worst performing drive, screw that. Would rather buy drives that perform as well as possible with the least failure rate.

In my recent experience there is not a lot of speed difference anymore between multiple manufacturers' 6TB to 12TB sized hard drives, when comparing between two competing products in the same rpm class (5400 or 7200) and areal density. Assuming similarly sized RAM cache on drive and not something like a drive with 64GB of SSD cache (hybrid drive).

Re: Backblaze Hard Drive Stats for 2018

#30
post #24

I realize my comment is a tangent. I'm hoping folks might be understanding and hopefully have some advice. If you have terabytes to back up, are there still any backup services left that'll let you ship them a drive for a faster initial backup?

AWS has the Snowball program. They ship you what is essentially a network storage device with 10G ethernet, and you upload data over your local 10G network using their protocols, then ship back and they ingest into S3/Glacier.

Haven't used it personally, but did a fair amount of digging ~3 years ago. It was a potential backup solution, but we ended up shipping a 4U server full of 4TB drives to a partner for off-site backup, since they needed routine access anyways.

Check out the AWS page: https://aws.amazon.com/snowball/

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