ADLINK Technology MECS-7211, Руководство пользователя

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Preliminary
70
MECS-7211
BIOS Item Options Description
Enable
Auto states: invalid (I), snoopAll (A), and
Shared (S). The snoopAll (A) means
the data may exist in another socket or
modified state. Shared (S) state means
the data may be shared across one or
more socket’s caches. When reading
memory and directory line is in the A
state, we must snoop all the other
sockets because another socket may
have the line in modified state. If this is
the case, the snoop will return the
modified data. However, it may be the
case that all snoops come back a miss
if another socket read the line earlier
and then dropped it from its cache
without modifying it.
Disable
– allows processing memory
directory states as described above.
Enable
– where a line in A state
returns only snoop misses, the line will
be transition to S state. Subsequent
reads to the line will encounter it in S
state and not have to snoop, saving
latency and snoop bandwidth.
LLC dead line alloc Disable
Enable
Auto
In CPU cache scheme, mid-level cache
(MLC) evictions are filled into last-level
case (LLC). When lines are evicted
from MLC, core can flag them as
“dead”. This means that lines are not
likely to be read again. This option
allows dropping dead line and never
fills them into LLC if the option is
disabled. When it is enabled, the LLC
can opportunistically fill dead lines into
LLC if space is available.