Traffic Analysis trace buffer wrapped on cc______
Check the BUFSIZE parameter in SYS1.PARMLIB(cc______)
VIP traffic analysis provides data regarding IP fragmentation, TN3270 response time, and TCP application performance.
VIP traffic analysis acquires data from the IBM component trace buffer, which has a default buffer size of 8M. SDS recommends increasing it to at least 64M, more if a VIP agent will monitor IP fragmentation. The precise size necessary depends on what VIP is configured to monitor and how much traffic goes through a TCP/IP stack.
Increase the buffer size by editing the BUFSIZE(xxM) parameter in SYS1.PARMLIB(CTIEZBnn).
TRACEOPTS
/* -----------------------------------------
/* ON OR OFF: PICK 1
/* -----------------------------------------
ON
/* OFF
/* -----------------------------------------
/* BUFSIZE: A VALUE IN RANGE 128K TO 256M
/* -----------------------------------------
BUFSIZE(64M)
If the component trace buffer is too small, you risk two problems:
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1. Lost data for fragmentation, TN3270 response time, and TCP application performance.
2. Increased CPU demands by VIP.
When the buffer is too small, the data written to it by the mainframe system may wrap and data may be overwritten and destroyed before VIP can retrieve and report it.
When the data wraps, VIP tries to compensate by reading the buffer twice as often. By default, VIP reads every second. If that’s not often enough, VIP will go to every 1/2 second, then 1/4 second, and so on, down to .05 second. The more often VIP reads the buffer, the more CPU VIP uses.