6 ms·
> Measuring only one-and-half-feet by three-and-half-feet by six inches, each Diskotech box holds as much as a petabyte of data This number is very interesting
by riobard 11y ago
> Measuring only one-and-half-feet by three-and-half-feet by six inches, each Diskotech box holds as much as a petabyte of data
This number is very interesting. Basically Diskotech stores 1PB in 18" × 6" × 42" = 4,536 cubic inch volume, which is 10% bigger than standard 7U (17" × 12.2" × 19.8" = 4,107 cubic inch).
124 days ago Dropbox Storage Engineer jamwt posted here (https://news.ycombinator.com/item?id=10541052 https://news.ycombinator.com/item?id=10541052) stating that Dropbox is "packing up to an order of magnitude more storage into 4U" compared to Backblaze Storage Pod 5.0, which is 180TB in 4U (assuming it's the deeper 4U at 19" × 7" × 26.4" = 3,511 cubic inch). Many doubted what jamwt claimed is physically possible, but doing the math reveals that Dropbox is basically packing 793TB in 4U if we naively scale linearly (of coz it's not that simple in practice). Not exactly an order of magnitude more but still.
Put it another way, Diskotech is about 30% bigger in volume than Storage Pod 5.0 but with 470% more storage capacity.
That was indeed some amazing engineering.
- jamwt 11y agoThe difference to get even higher is our system supports host-managed SMR disks that come in 10T and 14T sizes.
- riobard 11y agoIs that in production system now? W-O-W! :O
- jl6 11y agoI've never heard of a 14TB disk drive. Is that what you mean? Who makes these?
- benologist 11y agohttp://www.theregister.co.uk/2016/03/03/samsung_2_5_inch_15tb_ssd/ http://www.theregister.co.uk/2016/03/03/samsung_2_5_inch_15t... 2.5" 15TB ... and SSD, and expected to get a lot bigger too!
- jl6 11y agoBut that's not an SMR drive.
- Sanddancer 11y ago10 TB drives can be gotten off the shelf -- http://www.hgst.com/products/hard-drives/ultrastar-he10 http://www.hgst.com/products/hard-drives/ultrastar-he10 -- and 14 TB drives are probably in the state of availability for large customers; it's not unusual for drive makers to make available drives coming down the pipe to certain customers.
- jl6 11y agoTrue, it's just that they also tend to shout about upcoming drives and boast that they are previewing to select customers. Case in point, HGST marketing is in full swing on that He10 but good luck finding any stock in a mainstream retailer.
- jamwt 11y agoYep, vendors do sometimes provide stock to large customers ahead of general availability.
- olavgg 11y agoWhat interface and protocol do your drives have/use? Is it SATA, SAS or a custom interface/protocol?
- jamwt 11y agoSATA SMR disks, zone management is ZAC.
- james_cowling 11y agoTo be fair to Backblaze this level of storage density is really only possible with recent advances in disk technology (higher densities, SMR storage, etc). Also not everyone wants to be packing a petabyte into a box. At that level of density you need to invest a lot of effort in replication strategies, tooling, network fabric etc to handle failures with high levels of availability/durability.
- jamwt 11y agoYes, a 1PB+ failure domain only made sense because Magic Pocket is very good at automatic cluster management and repair.
- samstave 11y agoAre you using spindle or ssd or flash? (admittedly I dont know if you consider flash and ssd to be the same) What is your price per GB raw?
- jamwt 11y ago> Are you using spindle or ssd or flash? (admittedly I dont know if you consider flash and ssd to be the same) We have flash caches (NVMe) in the machines, but the long-term storage devices are spindle--PMR and SMR. > What is your price per GB raw? I cannot disclose, exactly, but it is well below any other public price I've seen.
- atYevP 11y agoYev from Backblaze here -> Yup! It's pretty entertaining! Granted we only store 180TB b/c we use primarily 4TB drives and it's inexpensive for us to do so. If we had 10TB drives in there we'd be pushing up to 450TB per pod, but the price for us would increase dramatically. Pod 6.0 will be a bit more dense!
- Sanddancer 11y agoNot to knock Dropbox's engineering, because it is sexy, but there are off the shelf enclosures right now that will fit 90 drives in a 4u case. Given that said enclosures have full rack rails and all, and are narrower, I don't doubt that a more densely designed server is feasible in the least with dropbox's design.
- gshx 11y agoThere are other concerns to keep in mind, eg. the upgradability of storage to use next gen cards that use 3d nand, etc. I'm sure they thought through a list of concerns before going this route.
- james_cowling 11y agoThese are standard-width rackmount chassis btw. They're 1.5x depth but otherwise it's standard 4U. The dimensions given are just an approximation.