Log devices can be tuned using the synchronous write bias property by selecting values of
latency, throughput, or read-only mode?
A.
True
B.
False
Explanation:
TheSynchronous write biasproperty has no read-only mode.
Value:Latency
*Synchronous writes are optimized for latency, leveraging the
dedicated log device(s), if any.
*Throughput
Synchronous writes are optimized for throughput.Data is written
to the primary data disks instead of the log device(s), and the writes
are performed in a way that optimizes for total bandwidth of the
system.
Note:This setting controls the behavior when servicing synchronous writes. By default, the system
optimizes synchronous writes for latency, which leverages the log devices to provide fastresponse times. In a system with multiple disjoint filesystems, this can cause contention on the
log devices that can increase latency across all consumers. Even with multiple filesystems
requesting synchronous semantics, it may be the case that some filesystems are more
latency-sensitive than others. A common case is a database that has a separate log. The log is
extremely latency sensitive, and while the database itself also requires synchronous semantics, it
is heavier bandwidth and not latency sensitive. In this environment, setting this property to
‘throughput’ on the main database while leaving the log filesystem as ‘latency’ can result in
significant performance improvements.Note that this setting will change behavior even when
no log devices are present, though the effects may be less dramatic.
Sun ZFS Storage 7000 System Administration Guide, Synchronous write bias