Page 89 - slides.dvi

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I/O
Operating
I/O
use
is
and
data
Systems
a
—
Improving
reduce
reduce
reduce
context
balance
Improving
I/O
adaptive
(network
demands
#
DMA
I/O
data
major
copying,
Subsystem
CPU,
CPU
number
traffic
polling
where
switches
to
of
factor
Performance
interrupts
copying
due
(e.g.
in
performance:
by
memory,
buffering,
to
possible
execute
performance
especially
context
bus
etc
Linux
is
overall
using
a
and
device
interrupts
large
NAPI)
switches
stressful)
I/O
system
major
driver,
for
transfers,
best
kernel
remaining
performance
I/O
smart
OS
code,
throughput.
etc.
controllers,
challenge
85