Overview, Memory use for code, Memory use for transactions – Echelon LonTal Stack User Manual

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Appendix E: Appendix E


Determining Memory Usage for LonTalk

Stack Applications

Overview

The LonTalk Host stack allocates memory dynamically, so a direct measurement

of the memory usage might lead to an underestimate for memory usage,
especially for peak usage conditions. This appendix provides both static code

analysis and runtime measurements so that you can calculate more reliable

memory usage estimates.

Memory Use for Code

The following table lists the estimated memory required for the LonTalk Stack

code. The values will vary depending on the processor, operating system, and

compiler that you use.

Code Type

Bytes Required

Native LonTalk protocol stack and
LonTalk API

750 KB

IP-852 LonTalk protocol stack and

LonTalk API

855 KB

Native LonTalk to IP-852 Router

880 KB

Serial MIP driver

70 KB

SimpleDevice and SimpleIp852Device

example applications

30 KB

Ip852Router example application

15 KB

Memory Use for Transactions

The LonTalk host stack allocates memory for transactions at runtime, as they are
needed. On the Stack Configuration page of the LonTalk Interface Developer

utility, you can specify maximum allowed values for the number of simultaneous

receive transactions and for the number of simultaneous transmit transactions.
These values limit the amount of memory that the LonTalk host stack allocates

for transactions.
The following table lists the estimated amount of memory required for each type
of transaction. .

Transaction Type

Bytes Required

Transmit transaction

196

Receive transaction

400

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