WEB BROWSER-BASED CONFIGURATION
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• Amount of Read Ahead
Read-Ahead data is buffered in the RAID controller cache,
however, thereby cutting down on the amount of I/O traffic to
the disk. The Amount of Read Ahead defines how many data
of reading at a time, making more efficient use of the RAID
storage. This makes it possible to locate and re-issue the data
without repetitive hard parsing activities.
The Amount of Read Ahead parameter is used to allocate
an amount of memory in the cache memory the frequently
executed queries and return the result set back to the host
without real disk read execution. Default value is Auto: Con-
troller will base on the HDD number to set the amount of Read
Ahead value. You can select between 512KB ~ 16MB.
• Number of AV Stream
RAID controllers are required to have not only the function of
processing ordinary data but also the function of dealing with
AV (audio/video) stream data needing real-time processing.
Since the bus cycle used in RAID controller was designed to
transfer the computer data exactly, it was unsuitable for the
transfer of AV stream needing great band widths. They are
required to do some setting for the handshaking during the
processing of stream data. This setting is an object of trans-
ferring stream data efficiently on an existing RAID controller.
Normally you should not need to modify this value. Default
value is 6. You can select between 6~256.
To decide how to set AV stream play out parameter, you need
to check the Number of Stream, Amount of Read Ahead, and
Total Cache Memory during runtime. You can try to adjust the
three numbers to get the best performance as your require-
ment. Number of Stream shows the number of stream added
to the system, Amount of Read Ahead shows the amount
of Read Ahead data taken from the cache without real disk
execution, and Total Cache Memory shows the total available
memory being installed in the RAID controller.
• Optimize AV Recording
AV recording option is for video recording (no time limit), but
if used in normal operation, performance may be degraded.
This new feature there are 4 options; Disabled, Mode1, Mode2
