Got a new thing in the post to play with today, It's a SSD from 2014 with a whopping 8GB of storage. If that does not sound like a lot, it's because it isnt, but this thing has a hidden trick up it's sleeve... It's actually a RAM disk. Inside is 8GB of DDR3, and it exposes it over 12G SAS as a block storage device. But you may ask "That's kinda useless, since when you reboot you will lose all the data on the drive? Might as well load the chassis up with more RAM and have a page cache" Well. This thing also has 8GB of NAND... it just only uses it on power on and power off to restore/checkpoint itself, even during sudden power loss!
29821632@noc.social
replied 21 Apr 2023 23:13 +0000
in reply to: https://benjojo.co.uk/u/benjojo/h/1fg3VXJBtNCwxB1Pkr
@benjojo Oh cool find! Not seen that thing before.
Reminds me of the Gigabyte i-Ram. I wrangled a small fleet of servers with them. RAM over a SATA 1 interface with a >2hr but <10hr BBU. Extremely decent storage for the day!
benjojo
replied 21 Apr 2023 23:17 +0000
in reply to: https://noc.social/users/29821632/statuses/110239336999017181
@29821632 Nice! I've seen those before and always wondered if people had used them for DB servers and such! It would have made a lot of sense to!
benjojo
replied 21 Apr 2023 22:31 +0000
in reply to: https://benjojo.co.uk/u/benjojo/h/1fg3VXJBtNCwxB1Pkr
Since the datasheet does not explain how it powers down safely while keeping hold of it's data, we can take a look inside. We can see 8 super capacitors, Each one 2.5V and 110F(!) The case is clearly milled, this was very likely not a cheap device.
benjojo
replied 21 Apr 2023 22:59 +0000
in reply to: https://benjojo.co.uk/u/benjojo/h/Z1N6443jSBJyPLCc3H
Below the power board is the actual control board, This contains 8GB of DDR3 DRAM, and 8GB of NAND spread over many chips (likely to reduce the time needed to transfer the RAM to the NAND) At the heart of it is a I assume the real world use case for this was a database server or for WAL logs, something that needed to be fast, power safe, and not wear out (since DDR3 does not wear out like NAND does) Regardless, I need to actually hook this thing up to a SAS device to check that it still works. Just need to find the correct cables
Virtex 5 XC5VFX100T
, a FPGA that seems to go for at least £4000 (4,900 USD ish). Mostly proving that this was a very... very expensive device.
benjojo
replied 22 Apr 2023 09:47 +0000
in reply to: https://hachyderm.io/users/benjamineskola/statuses/110241303774054947
@benjamineskola likely yes, SSD/NAND does wear out, and still has latency/speed limits to it. While this removes it to the point where the SAS12G link is the bottleneck
benjojo
replied 21 Apr 2023 22:46 +0000
in reply to: https://benjojo.co.uk/u/benjojo/h/4ys9sWQD9tR91xGzRJ
The FPGA in this thing seems overkill, but also maybe 12G SAS and 23μs iops latency needs something like this? Huge device though, I assume reasonably huge power draw too. It seems that not many of these were made, since one of the serial numbers on the drive suggested it was #4000 ish
sfoskett@techfieldda..
replied 22 Apr 2023 00:53 +0000
in reply to: https://benjojo.co.uk/u/benjojo/h/6Zs2K4Yd6x9d3PH6qk
@benjojo the ZeusIOPS was an amazing device in its time! I was covering the storage industry at the time and it was the real deal!
benjojo
replied 22 Apr 2023 09:45 +0000
in reply to: https://techfieldday.net/users/sfoskett/statuses/110239730583636748
alarig@hostux.social
replied 22 Apr 2023 10:55 +0000
in reply to: https://benjojo.co.uk/u/benjojo/h/Z1N6443jSBJyPLCc3H
ellie@ellieayla.net
replied 24 Apr 2023 22:09 +0000
in reply to: https://benjojo.co.uk/u/benjojo/h/1fg3VXJBtNCwxB1Pkr
@benjojo How much of the chassis is dedicated to a bank of onboard capacitors to power the checkpoint on power loss?