µC/TCP-IP maintains counters and statistics for a variety of expected or unexpected error conditions. Some of these statistics are optional since they require additional code and memory and are enabled only if NET_CTR_CFG_STAT_EN or NET_CTR_CFG_ERR_EN is enabled (see Network Counters Configuration).
Statistics
µC/TCP-IP maintains run-time statistics on interfaces and most µC/TCP-IP object pools. If desired, an application can thus query µC/TCP-IP to find out how many frames have been processed on a particular interface, transmit and receive performance metrics, buffer utilization and more. An application can also reset the statistic pools back to their initialization values (see net_stat.h).
Applications may choose to monitor statistics for various reasons. For example, examining buffer statistics allows you to better manage the memory usage. Typically, more buffers can be allocated than necessary and, by examining buffer usage statistics, adjustments can be made to reduce their number.
Network protocol and interface statistics are kept in an instance of a data structure named Net_StatCtrs. This variable may be viewed within a debugger or referenced externally by the application for run-time analysis.
Unlike network protocol statistics, object pool statistics have functions to get a copy of the specified statistic pool and functions for resetting the pools to their default values. These statistics are kept in a data structure called NET_STAT_POOL which can be declared by the application and used as a return variable from the statistics API functions.
The data structure is shown below:
NET_STAT_POOL_QTY is a data type currently set to CPU_INT16U and thus contains a maximum count of 65535.
Access to buffer statistics is obtained via interface functions that the application can call (described in the next sections). Most likely, only the following variables in NET_STAT_POOL need to be examined, because the .Type member is configured at initialization time as NET_STAT_TYPE_POOL :
.EntriesAvail
This variable indicates how many buffers are available in the pool.
.EntriesUsed
This variable indicates how many buffers are currently used by the TCP/IP stack.
.EntriesUsedMax
This variable indicates the maximum number of buffers used since it was last reset.
.EntriesAllocatedCtr
This variable indicates the total number of times buffers were allocated (i.e., used by the TCP/IP stack).
.EntriesDeallocatedCtr
This variable indicates the total number of times buffers were returned back to the buffer pool.
In order to enable run-time statistics, the macro NET_CTR_CFG_STAT_EN located within net_cfg.h must be defined to DEF_ENABLED.
Error Counters
µC/TCP-IP maintains run-time counters for tracking error conditions within the Network Protocol Stack. If desired, the application may view the error counters in order to debug run-time problems such as low memory conditions, slow performance, packet loss, etc.
Network protocol error counters are kept in an instance of a data structure named Net_ErrCtrs. This variable may be viewed within a debugger or referenced externally by the application for run-time analysis (see net_stat.h).
In order to enable run-time error counters, the macro NET_CTR_CFG_ERR_EN located within net_cfg.h must be defined to DEF_ENABLED.