Statistics

Viewing/Capturing Statistics During Tracing

Statistics are displayed during tracing in pairs of rows (one for Frame statistics and one for Byte statistics), every 15 seconds. All of this output can be additionally written to a user specified logfile by using the -l option.

The following is a typical display of statistics during tracing:

Interpreting Statistics During Tracing

Column	Frames	Bytes
Total	The total number of frames received since tracing began.	The total number of bytes received since tracing began.
Sliced	The cumulative number of frames (since tracing began) that were artificially shortened to the maximum sliced frame size.	n/a
Lost	The cumulative number of frames lost due to software causes, since tracing began. In addition, there may be an indicator of frames lost due to hardware causes. See Lost Frames for more information on how to interpret these indicators.	The cumulative number of bytes lost since tracing began. The two causes of lost bytes are frame slicing and lost frames.
Rate	Frames/second measured over the current time interval.	Bytes/second measured over the current time interval.
%Util	n/a	LAN Utilization as calculated by the number of bytes/second compared to the maximum number of bytes/second for the media as reported by the MAC driver.
Avg	n/a	Average frame size in bytes, during the current time interval.

Error Counters Reported at the End of Tracing

The following NDIS statistics are monitored for change during tracing. If any of these values change, then a report is displayed on the console when tracing is ended. The report will have an entry for each one of the following values which has changed:

In the NDIS Service-specific Statistics Table:

total frames with CRC error
total frames discarded - no buffer space
total frames discarded - hardware error

In the NDIS Media-specific Statistics Table (802.3):

total frames with alignment error
total frames with overrun error

In the NDIS Media-specific Statistics Table (802.5):

FCS or code violations detected in repeated frame

These tables can be viewed separate from tracing, at any time, by using the MACSTAT.EXE utility (see the next section). In addition, these same tables are available using the BINDTREE utility, although the output is not as well formatted for statistics viewing.

Obtaining LAN Adapter Statistics Without Tracing

By using the MACSTAT.EXE utility, LAN adapter statistics can be captured at any time.

The syntax help for this utility can be obtained by running:

macstat ?

The output from this command is displayed below:

Statistics for the default NTRACE instance and the adapter 0 can be obtained by running MACSTAT with no parameters. It is important to note that MACSTAT is NOT a standalone utility. It requires the NTRACE.OS2 device driver to be installed and operational, in order to function.

Note that through MACSTAT, the user can clear the statistics and error counters in the MAC driver OR can force the driver to update these statistics before they are queried. These features allow the utility to support the full range of NDIS MAC drivers and the resulting variation in statistics support. Of course, some MAC drivers do not support statistics at all. In this case, MACSTAT is just as dependent upon the MAC driver as are the lost frame statistics that get displayed during tracing.

LAN Adapter Statistics - Results

MACSTAT queries the specific status and multiple tables of statistics from the MAC driver specified by the user.

Sample output from MACSTAT follows:

Network Trace for OS/2 Release 1.1
NDIS MAC Statistics Utility v1.05
(c) Copyright Golden Code Development Corp., 1999, 2000

IBM EtherJet PC Card.

SERVICE-SPECIFIC STATUS:

       Last diagnostic Date/Time           NEVER
       MAC status - bit mask               0000001F:
          Hardware fully operational
          MAC is bound
          MAC is open/functional
       Current packet filter               0003
          directed and multicast / group and functional
          broadcast
       Last clear stats Date/Time          391BA8F2
       Frames received: total              3646
       Receive fail: CRC error             0
       Frames received: total bytes        2450189
       Receive fail: lack of buffers       0
       Frames received: multicast          0
       Frames received: broadcast          709
       Rcv fail: hardware error            0
       Frames sent: total                  2873
       Frames sent: total bytes            2526057
       Frames sent: multicast              0
       Frames sent: broadcast              0
       Send fail: time-out                 NOT SUPPORTED
       Send fail: hardware error           NOT SUPPORTED

ETHERNET MEDIA-SPECIFIC STATISTICS:

       Version                              1
       Receive fail: Alignment error        0
       Receive fail: Overrun                0
       Frames sent: after deferring         NOT SUPPORTED
       Frames not sent: Max collisions      0
       Total late collisions                0
       Frames sent: after 1 collision       0
       Frames sent: multpl collisions       NOT SUPPORTED
       Frames sent: CD heart beat           NOT SUPPORTED
       Lost carrier sense during tran       0
       Total number of underruns            NOT SUPPORTED