https://www.ibm.com/developerworks/mydeveloperworks/blogs/InsideSystemStorage/entry/watson_what_is_the_smartest_machine_on_earth7?lang=en https://www.ibm.com/de

https://www.ibm.com/developerworks/mydeveloperworks/blogs/InsideSystemStorage/entry/watson_what_is_the_smartest_machine_on_earth7?lang=en https://www.ibm.com/developerworks/mydeveloperworks/blogs/In... "Several readers of my blog have asked for details on the storage aspects of Watson. Basically, it is a modified version of IBM Scale-Out NAS [SONAS] that IBM offers commercially, but running Linux on POWER instead of Linux-x86. System p expansion drawers of SAS 15K RPM 450GB drives, 12 drives each, are dual-connected to two storage nodes, for a total of 21.6TB of raw disk capacity. The storage nodes use IBM's General Parallel File System (GPFS) to provide clustered NFS access to the rest of the system. Each Power 750 has minimal internal storage mostly to hold the Linux operating system and programs. When Watson is booted up, the 15TB of total RAM are loaded up, and thereafter the DeepQA processing is all done from memory. According to IBM Research, "The actual size of the data (analyzed and indexed text, knowledge bases, etc.) used for candidate answer generation and evidence evaluation is under 1TB." For performance reasons, various subsets of the data are replicated in RAM on different functional groups of cluster nodes. The entire system is self-contained, Watson is NOT going to the internet searching for answers. "