NEC POWERMATE ES Series, Инструкция по обслуживанию и справочник

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Glossary 15
WRAM
Windows RAM. A type of RAM that supports two ports. This enables a video adapter to
fetch the contents of memory for display at the same time that new bytes are being pumped
into memory. This results in much faster display than is possible with conventional single-
port RAM. WRAM is similar to VRAM, but achieves even faster performance at less cost
because it supports addressing of large blocks (windows) of video memory. See VRAM and
SGRAM.
write
To record or store information to a storage device.
write-back
Also called copy back. A cache strategy where write operations to data stored in the internal
microprocessor L1 cache aren’t copied to system memory until absolutely necessary. In
contrast, a write-through cache performs all write operations in parallel; data is written to
system memory and the L1 cache simultaneously. Write-back caching yields somewhat
better performance than write-through caching because it reduces the number of write
operations to main memory. See cache and write-through.
write-through
Also write-thru. Write-through characterizes a cache strategy where data is always written
into system memory when data is written by the CPU. See cache and write back.