Veritas Volume Manager 5.0.1 Administrator's Guide, HP-UX 11i v3, First Edition, November 2009

Tunable parameters for VxVM
Table 16-1 lists the kernel tunable parameters for VxVM.
Table 16-1
Kernel tunable parameters for VxVM
DescriptionParameter
The interval at which utilities performing recoveries or
resynchronization operations load the current offset into
the kernel as a checkpoint. A system failure during such
operations does not require a full recovery, but can continue
from the last reached checkpoint.
The default value is 10240 sectors (10MB).
Increasing this size reduces the overhead of checkpoints on
recovery operations at the expense of additional recovery
following a system failure during a recovery.
vol_checkpt_default
The count in clock ticks for which utilities pause if they
have been directed to reduce the frequency of issuing I/O
requests, but have not been given a specific delay time. This
tunable is used by utilities performing operations such as
resynchronizing mirrors or rebuilding RAID-5 columns.
The default value is 50 ticks.
Increasing this value results in slower recovery operations
and consequently lower system impact while recoveries are
being performed.
vol_default_iodelay
Performance monitoring and tuning
Tuning VxVM
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