Viewing profile — andy4blaze

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 …

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 a…

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 las…

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 …

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 l…

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 fail…

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 ca…

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, in…

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.

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 …

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 temperatur…

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…

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 a…

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.

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 wo…

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 SSD…

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.

In the Backblaze case, they are securely wiped clean and then recycled.

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. Sto…

Website is fine, Backup service is fine. Blog is overloaded and we're working on it.

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 b…

The Botezatu et al paper is quite good. The recommendations they make are well worth further consideration in our environment. -- Andy at Backblaze.

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 ca…

Nice analysis.

Andy from Backblaze here: Here's the post we did about that if you're interested: https://www.backblaze.com/blog/crowdsourcing-hard-drives/