Abstract: The specification may disclose a computer system that may operate a portion of available memory as backup to a primary memory, and the computer system may be adapted to test the backup memory for memory errors at times other than execution of power-on self-test procedures.

Abstract: The specification discloses a server system implementing hot pluggable memory boards in an architecture using X86 processors and off-the-shelf operating system, such as Windows® or Netware, which do not support hot plugging operations. Thus, the specification discloses systems and related methods for hot plugging main memory boards transparent to, and without the help of, the operating system. The operating system need only have the ability to recognize additional memory in order to use it. Moreover, the specification discloses a related set of memory error detection and correction techniques, again which are implementing transparent to, and without the help of, the operating system.

Abstract: A computer system implements hot mirroring for main system memory. That is, the computer system permits a user to hot plug a new memory board into the system and the system will respond by switching to a mirrored memory mode in which write cycles are performed to both memory boards (new and old). Once a new board is hot plugged into the system, the contents of the old board are copied over, in a background mode, to the new board so that both boards will have the same data. Because this background copying process may take a non-trivial amount of time and may detrimentally interfere with other system traffic, the system a user to exert control over the relative speed of the background copying so as to trade-off the time it takes to switch over to the mirroring mode versus the impact on on-going system behavior.