Requirements for computing room

A. Gianoli, M. Serra, P. Valente

2 rows: 18 + 18 racks

cpu/storage “guess”From “today” extimate (Alberto, Paolo, …)

• storage 200 ÷ 300 TB – ~24 TB/ box (raid 0+1), 800 Watt, 3 rack unit box– ~9 ÷ 13 box, ~7.2 ÷ 10.4 KW, 27 ÷ 39 rack unit

• CPU: 8core box, 500W, 2 rack unit (for network cards)– L1 ~30 ÷ 50 box, L2/L3 ~30 ÷ 35 box

– ~60 ÷ 85 box, ~30 ÷ 42.5 KW, 120 ÷ 170 rack unit (LKr L1 downstairs)

• Total: ~37 ÷ 53 KW, 147 ÷ 209 rack unit, • + networks switch

“space”• there is space for 2 rows of 18 racks (40/42 units)

• for our needs should be enough 1 row but would be convinient to setup the water pipes (for rack cooling), the electric distribution and the network uprights to have an easy way to instrument the second row– the extra cost should be not so relevant

• water pipes under the floor • electric blindo-barr (or cables?) from ceiling to rack power

distribution• network cables/fibers from ceiling is ok?

cooling• having enough space It’s convinient to use ~half filled racks

– cooling is less expensive and easier( ~ 200 rack units -> 10 racks )

• rack cooling via a rear door element– cooling capacity 10KW

• (this solution is becaming a cern standard)– water distribution to each door– external chiller

(we have already the rack technical specification)

• “moderate” room cooling

• ~100 KW cooling chiller (safety factor ~2)– it is possible to optimize the tender

UPS and power distribution

• if we consider to instrument 1 row a ~120KVA UPS shuld be enough (safety factor ~2)– if we could have an expandable unit would be better (for the second

row)

• blindo-barr vs traditional cabling?• flexible main power panel?