Taken from an Ars Technica article on Facebook's DIY servers

 

Each storage server has 2 trays of 15 4TB drives, that's a lot of disk space in what looks like a 2RU chassis.

 

Wonder if they take orders

How do they keep them cool?

OCP Knox.  They're pretty cool, we're looking at them and OCP servers for Hadoop at work.

 

http://www.opencompute.org/

How do they keep them cool?

 

 

You can see the cooling better in this picture. Six rows of two 60mm fans. The fans are mounted on a modular bracket so if a fan dies you pop the bracket out and put a new one in.

 

I wonder how you interface with the storage..  are they presented as LUNs, FC?

docs say they are just using SAS and expander boards.

Interesting, I guess they just need slow and cheap storage. Object storage I guess...

From what I've read, they have entire servers (hundreds/thousands) set up as dedicated memcache servers because they found that SSD wasn't fast enough, I think I read that they transitioned away from SQL to nosql databases because of the severe level of data distribution they need. Photos have presented a special challenge, as most people only look at recent photo albums, but expect all their photos to be "instantly" available even though they never get looked at. Hence Facebook's desire for a "cold storage" technology hard drive (see my other post.)

one of the best high density one's i have seen is the nexsan server

 

4u height , 3 bays with each bay having 20 disks, total capacity 60 disks in 4 u cabinet.  Powers down when not in use.

 

 

 

From what I've read, they have entire servers (hundreds/thousands) set up as dedicated memcache servers because they found that SSD wasn't fast enough, I think I read that they transitioned away from SQL to nosql databases because of the severe level of data distribution they need. Photos have presented a special challenge, as most people only look at recent photo albums, but expect all their photos to be "instantly" available even though they never get looked at. Hence Facebook's desire for a "cold storage" technology hard drive (see my other post.)

 

You can do something similar with openstack swift.  It's kinda like hadoop without all the metadata object storage stuff.