http://en.wikipedia.org/wiki/Google_platform
Original hardware
The original hardware (ca. 1998) that was used by Google when it was located at Stanford University, included:
- Sun Ultra II with dual 200 MHz processors, and 256MB of RAM. This was the main machine for the original Backrub system.
- 2 x 300 MHz Dual Pentium II Servers donated by Intel, they included 512MB of RAM and 9 x 9GB hard drives between the two. It was on these that the main search ran.
- F50 IBM RS/6000 donated by IBM, included 4 processors, 512MB of memory and 8 x 9GB hard drives.
- Two additional boxes included 3 x 9GB hard drives and 6 x 4GB hard drives respectively (the original storage for Backrub). These were attached to the Sun Ultra II.
- IBM disk expansion box with another 8 x 9GB hard drives donated by IBM.
- Homemade disk box which contained 10 x 9GB SCSI hard drives.
Current hardware
Servers are commodity-class x86 PCs running customized versions of Linux. The goal is to purchase CPU generations that offer the best performance per dollar, not absolute performance. Estimates of the power required for over 450,000 servers range upwards of 20 megawatts, which cost on the order of US$2 million per month in electricity charges.
Specifications:
- Upwards of 15,000 servers ranging from 533 MHz Intel Celeron to dual 1.4 GHz Intel Pentium III (as of 2003). A 2005 estimate by Paul Strassmann has 200,000 servers, while unspecified sources claimed this number to be upwards of 450,000 in 2006.
- One or more 80GB hard disks per server (2003)
- 2–4 GB of memory per machine (2004)
The exact size and whereabouts of the data centers Google uses are unknown, and official figures remain intentionally vague. In a 2000 estimate, Google's server farm consisted of 6000 processors, 12,000 common IDE disks (2 per machine, and one processor per machine), at four sites: two in Silicon Valley, California and one in Virginia. Each site had an OC-48 (2488 Mbit/s) internet connection and an OC-12 (622 Mbit/s) connection to other Google sites. The connections are eventually routed down to 4 x 1 Gbit/s lines connecting up to 64 racks, each rack holding 80 machines and two ethernet switches. The servers run custom server software called Google Web Server.
They were PII 400MHz and cost me £700 each. £1400 on the CPUs alone. I must have been mad. Or were they £350 each, £700 in total? I can't remember.
