andy4blaze

5 ms·

1.
by andy4blaze 3y ago
Andy Klein from Backblaze here. We have done some survival analysis (kaplan-meier curves). In our case, we need to have a reasonable number of failures over the observation period to get decent results. You can take a look at some of our wo
2.
by andy4blaze 3y ago
Andy Klein from Backblaze here. Your point is a good one in that temperature fluctuation can be an important factor. We actually sample smart stats, which contain the temperature attribute, multiple times a day looking for such changes. The
3.
by andy4blaze 5y ago
Andy from Backblaze here: The WDC model (WUH721816ALE6L0) seems to only be available in Europe, not the US. It was 549,00 EUR last time I looked back in November. I believe the last digit is about data erasure with 0 being "Instant Se
4.
by andy4blaze 5y ago
Andy for Backblaze here: I looked at that 3-4 years ago. It looks like power cycling increased failure rates, but we don't power cycle our systems very often, maybe 1-2 a year, so not the best use case. This is on my list for a relook
5.
by andy4blaze 5y ago
Andy for Backblaze here: A while back we did an analysis of drive failure over time, i.e. the bathtub curve. It is probably a good idea to update that, as I believe we are seeing lower failure rates upfront these days.
6.
by andy4blaze 5y ago
Andy at Backblaze here. We do look at drive model failure over time. We did a post on this topic several years ago, 2015? At the time, most drive followed the bathtub curve of failure, but I'm not sure that is still the case. I think i
7.
by andy4blaze 6y ago
Andy from Backblaze here. Larger drives do take longer to rebuild, but to date we haven't changed the encoding algorithms we built. There are other strategies like cloning which can reduce rebuild time. We can also prioritize rebuild
8.
by andy4blaze 6y ago
Andy at Backblaze here. All the drives are in data centers with temps around the 75-78 degree mark. Vibrations are kept to a minimum via the chassis design. We publish the data, including the SMART stats for all of the drives and there are
9.
by andy4blaze 6y ago
Andy from Backblaze here. Actually you can download a spreadsheet with all the data from the tables. There's a link at the end of the post. Better than parsing HTML for the data.
10.
by andy4blaze 6y ago
Andy from Backblaze here. Nice thinking about the bulk ordering and considerations for RAID. All things we have considered. We use our own Reed-Solomon encoding with a 17/3 set-up across 20 drives across 20 different systems, we cal
11.
by andy4blaze 6y ago
Andy at Backblaze here. We've looked at this and the one "issue" is the consistency of the environments from the community data. In our DCs, the drives are kept a decent temperature, hardly ever moved, and our DC tech sing t
12.
by andy4blaze 6y ago
The average cost per GB is about $0.02/GB or $20/TB for the drive. Electricity varies based on the data center and the negotiated or local rates, so harder to calc. I like the idea of the chart, but may be tough to get the right
13.
by andy4blaze 6y ago
Andy at Backblaze here. To put a pin in it, the three main factors for which drives we use are cost, availability and reliability. We have control over reliability as our systems are designed to deal with drive failure. That leaves the m
14.
by andy4blaze 6y ago
Andy at Backblaze here: Good to know. We used to do this with the lifetime stats, but that got lost somewhere along the way. I'll look at getting them back. Thanks.
15.
by andy4blaze 6y ago
Andy at Backblaze here. We use SSDs in our core servers and more recently in boot drives as they both need to speed. To store data in our case we don't need the speed so its not worth it yet. Given the amount of data growth, most pred
16.
by andy4blaze 7y ago
Andy from Backblaze here: The capacity of the boot drives ranges from 80 to 500gb typically. They are mostly hard drives with some SSDs added recently. We are switching over to SSDs for boot drives. The workload is reasonable, but on the
17.
by andy4blaze 8y ago
Andy from Backblaze here. Thanks for pointing it out. The correct range is low: 0.5% to high: 1.1%. We have updated the chart.
18.
by andy4blaze 10y ago
In the Backblaze case, they are securely wiped clean and then recycled.
19.
by andy4blaze 10y ago
I suppose if you had a single 32TB drive that went offline for say a week, and then once it came back online you'd have some type of pent up demand and a "slow" transfer speed. Storage systems in general spread the load acro
20.
by andy4blaze 10y ago
Website is fine, Backup service is fine. Blog is overloaded and we're working on it.
21.
by andy4blaze 10y ago
The Backblaze Vault design mitigates that as the "raid array" is scattered across 20 different Storage Pods in twenty different racks. You'd need more than three racks to go down before you would be offline. Backup systems
22.
by andy4blaze 10y ago
The Botezatu et al paper is quite good. The recommendations they make are well worth further consideration in our environment. -- Andy at Backblaze.
23.
by andy4blaze 10y ago
Besides stock management, they help use determine the overall health of a Storage Pod or Vault. They also help find trouble with other components. For example, if a backplane or cable were failing, the drives via their SMART stats may not
24.
by andy4blaze 10y ago
Nice analysis.
25.
by andy4blaze 12y ago
Andy from Backblaze here: Here's the post we did about that if you're interested: https://www.backblaze.com/blog/crowdsourcing-hard-drives/