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@@ -1,4 +1,4 @@
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-$Id: IMPLEMENTATION.txt,v 1.1 2005/02/10 16:38:09 gdt Exp $
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+$Id: IMPLEMENTATION.txt,v 1.2 2005/02/15 17:10:03 gdt Exp $
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This file contains notes about the internals of the BGP
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implementation. The initial impetus is understanding the memory usage
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@@ -150,10 +150,18 @@ bgpd.c
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Question: How much memory does quagga's bgpd use as a function of
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state received from peers?
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-It seems that a struct bgp_info is kept for each prefix, and this has
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-its own struct attr. aspath, etc. are 'interned' and shared.
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-So, it seems that 144 bytes are used per received prefix, plus storage
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-for all unique aspaths received.
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+It seems that a struct bgp_info is kept for each prefix. The "struct
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+attr *" is interned, and variables within that are interned. So, 40
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+bytes are kept per received prefix, plus interned shared values. This
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+could be 36 if 'int suppress' where changed to a u_char and moved to
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+be with the other u_chars. Without MPLS, this could be 32 bytes.
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+Note that 8 bytes of this is linked list overhead, meaning that 24
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+bytes are the raw per-prefix storage requirements.
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+
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+Also, a struct bgp_damp_info is apparently maintained per route; this
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+is fairly large (about 44 bytes).
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+
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+[TODO: the role of struct bgp_node.]
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* TIME COMPLEXITY
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