DataDirect Networks S2A9550, Руководство пользователя

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D a t a D i r e c t N e t w o r k s S 2 A 9 5 5 0 U s e r G u i d e
M a n a g i n g t h e S 2 A 9 5 5 0
NOTE : It is recommended that you run LUN VERIFY in continuous mode, if at all possible, since it can
help increase disk reliability.
The
LUN DELAY=x
command sets the system verify delay value to 'x'. The verify delay value
determines how long a verify operation will pause after it reaches the verify extent. This parameter
slows down the verify operation so that it will not affect the performance of the system (except in the
case where “x” is set to 0, as described below).
DELAY=0
will remove all delays so that the verify
operation will go as fast as possible; however, this will slow down the performance of the system.
This value is in 100 millisecond increments. The range for “x” is 0 to 1000. Default is 30.
The LUN EXTENT=x command sets the system verify extent value, “x”, in Mbytes. The verify extent
determines how much data can be verified before the verify operation must pause. This parameter
slows down the verify operation so that it will not affect the performance of the system. Increasing
the extent value will allow more data to be verified in a single pass. The range for “x” is 1 to 128
Mbytes. Default is 16 Mbytes.
3.3.5.3 SES Device Monitoring Rate
The SES device monitoring rate can be adjusted to minimize its impact on system performance.
The
SES M_WAIT
command displays the current setting in seconds
(Figure 3-42)
.
The SES M_WAIT=x command sets the SES device monitoring rate for the system in seconds. Valid
range is 4 to 90 seconds. The default monitoring rate is 6 seconds.
NOTE : Improper use of this command can prevent the SES monitors from detecting an enclosure fault
before the enclosure automatically shuts down.
3.3.5.4 Host Command Timeout
The Host Command Timeout parameter allows the system to free up resources and make them
available to other users if the request from a particular user cannot be completed. This helps to
improve performance in a SAN environment where there are a lot of users accessing the storage.
The HOST TIMEOUT=x command sets the host command timeout for an I/O request in seconds. Valid
range is 1 to 512 seconds. Default setting is 30 seconds.
Figure 3-42 SES Device Monitoring Rate
S2A [1]: ses m_wait
SES timer m_wait = 6 seconds