Energy management

Owned by John Ousterhout
Last updated: Mar 31, 2009Version comment
1 min read
  • Does RAMCloud change the energy equation for a datacenter?
  • What if discs were essentially never turned on? Would this improve energy usage dramatically?
    • After a very quick glance around:
    • current HDs: 9W active, some 8W idle, some down to 5W, 1W standby
    • current SSDs: 2.5W active, 0.06W idle
    • so, perhaps the elimination of up to 8W per disk
    • could save 80kW or on 10k machines, or more with any redundancy
  • If we were to use flash based memory, like Fusion-IO for example, we could save even more power:
    • Current DRAMs - ~ 4.5 W per GB (question) - 160/320 W for 32/64 GB respectively
    • Fusion IO drive - claims ~ 120 W for 160 GB device (last gen device costs ~ 30 - 40 $ per GB)
    • Latency: < 50 us for read