2 commsmemfree(2), 3 commsmemfree(3) – Campbell Scientific CR800 and CR850 Measurement and Control Systems User Manual
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Section 10. Troubleshooting
413
Table 110. CommsMemFree(1) Defaults and Use Example, TLS
Active
Example
Buffer
Category
Condition:
reset, TLS active.
Buffer count:
CommsMemFree(1) =
230999960.
Condition:
TLS enabled, no
active
TLS connections.
Connected to
LoggerNet on
TCP/IP.
Buffer Count:
CommsMemFree(1) =
228968437.
Numbers of buffers
in use (reset count –
in-use count)
tiny 160
137
23
little 99
84
15
medium 99
96
3
large 30
28
2
huge* 2
2
0
*If email clients using TLS are active, huge will be decremented along with some of the others.
10.4.3.2 CommsMemFree(2)
CommsMemFree(2) displays the number of memory "chunks" in "keep" memory
(p. 435)
used by communications. It includes memory used for PakBus routing and
neighbor lists, communication timeout structures, and TCP/IP connection
structures. The PakBusNodes setting, which defaults to 50, is included in
CommsMemFree(2). Doubling PakBusNodes to 100 doubles
CommsMemFree(2) from ≈300 to ≈600 (assuming a large PakBus network has
not been just discovered). The larger the discovered PakBus network, and the
larger the number of simultaneous TCP connections, the smaller
CommsMemFree(2) number will be. A PakBusNodes setting of 50 is normally
enough, and can probably be reduced in small networks to free memory, if
needed. Reducing PakBusNodes by one frees 224 bytes. If
CommsMemFree(2) drops and stays down for no apparent reason (a very rare
occurrence), please contact a Campbell Scientific applications engineer since the
CR800 operating system may need adjustment.
10.4.3.3 CommsMemFree(3)
CommsMemFree(3) Specifies three two-digit fields, from right (least
significant) to left (most significant):
• lilfreeq = "little" IP packets available
• bigfreeq = "big" IP packets available
• rcvdq = IP packets in the received queue (not yet processed)
At start up, with no TCP/IP communication occurring, this field will read 1530,
which is interpreted as 30 lilfreeq and 15 bigfreeq available, with no packets in
rcvdq. The Ethernet and/or the PPP interface feed rcvdq. If
CommsMemFree(3) has a reading of 21428, then two packets are in the received