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How a probe uses RAM
314 GigaStor (23 Feb 2018) — Archive/Non-authoritative version
Figure 145: How packets move through Observer’s memory
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The capture card receives data off the network.
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The capture card passes data into RAM. In the RAM it goes into the packet
capture buffer and the statistics queue buffer.
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The statistics queue buffer passes the information to the statistics
memory configuration.
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The statistics memory configuration passes the data to the real-time
graphs.
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The Network Trending Files receive data from the statistics queue buffer
through the NI trending service, where they are written to disk.
The following steps occur only if you are writing the data to disk through a
packet capture to disk or a GigaStor capture.
If you are using packet capture to disk, the packet capture buffer passes the data
to the operating system’s disk.
If you are using GigaStor capture, the statistics queue buffer and the packet
capture buffer passes the information to the RAID.
A few notes about how some buffers are used:
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Packets received by the statistics queue buffer are processed and put in
the collected statistics buffer.
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Data for network trending comes from the statistics queue buffer, then
it is written to disk, and finally flushed from the buffer every collection
period.
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The collected statistical buffer does not use first-in, first-out to determine
statistics. Therefore, after the statistic limit is reached the remaining data
is no longer counted; however, data for known stations continue to be
updated indefinitely.
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Regardless of whether Observer is using reserved memory, the statistics
memory, statistics queue buffer, and packet capture buffer function the
same. The storage space available for storing packets in memory increases
though when you reserve memory.