Other advantage of using an NVRAM
instead of another type of memory (such as a flash memory) is based on the fact that the NVRAM
is a read-write memory and, therefore, the access to the stored data is simple and fast.
The machines were each able to handle 38 messages/second (48 assuming NVRAM
However, our theorem shows that there is some sequence of crashes that can drive a standard Data Link protocol (which has no NVRAM
) into a state such that r [not element of] [s, s + w].
A complete, high-performance way around these parity update problems in RAID-5 is to use significant quantities of NVRAM
with reliable battery backup.
Additional features include up to 2 GB of DDR2 SDRAM with ECC per processor, 128 MB boot Flash with write protection, up to 4 GB Flash-based file storage, protected backup boot flash, 128 KB NVRAM
, two Gigabit Ethernet (GbE) interfaces (one per processor) and selectable EIA-232/422 serial ports.