MustGather: Collect Troubleshooting Data / Read First / Fix List for TCPIP CSM Storage
for z/OS Communications Server

Resolving The Problem

• For TCP/IP z/OS 1.6 R160 IP R160
• For TCP/IP z/OS 1.7 R170 IP R170
• For TCP/IP z/OS 1.8 R180 IP R180
• For TCP/IP z/OS 1.9 R190 IP R190
• For TCP/IP z/OS 1.10 R1A0 IP R1A0
• For TCP/IP z/OS 1.11 R1B0 IP R1B0
• For TCP/IP z/OS 1.12 R1C0 IP R1C0
• For TCP/IP z/OS 1.13 R1D0 IP R1D0
• For TCP/IP z/OS 2.1 R210 IP R210
• For TCP/IP z/OS 2.2 R220 IP R220
• For TCP/IP z/OS 2.3 R230 IP R230

• When coding IVTPRM00, FIXED MAX and ECSA MAX values must start in column one and only one space is allowed between fields.

• If CSM MAX ECSA is coded higher than 90% of the z/OS allowable ECSA (IEASYS00 ECSA) then CSM MAX ECSA will be adjusted to 90% of z/OS ECSA.

• IEASYSxx CSA parm must be adjusted to include the additional amounts of ECSA that CSM will be using.

• A shortage of CSM FIXED storage may result in ENOBUFS errors on a variety of TCP/IP Socket calls. The system programmer should consider increasing CSM MAX FIXED if ENOBUFS errors are reported by sockets applications running on the z/OS image.

• To dynamically change the ECSA and FIXED CSM values use the following command:

MODIFY net,CSM,ECSA=value,FIXED=value
Note:
* net is your VTAM proc name
* value for ECSA can be in K or M ranging from 1024K to 2048M
* value for FIXED caan be in K or M ranging from 1024K to 30720M
Guideline: CSM ECSA and CSM data space can be requested to be fixed. z/OS ensures the real frame that is backing the storage matches the CSM data space type of request. For example: CSM DSPACE64 buffers are backed with a real frame that is above the 2G line.

• In z/OS® V1R13, the processing of IPAQENET and IPAQENET6 INTERFACE statements is enhanced. Coding the WORKLOADQ parameter on these INTERFACE statements now enables the QDIO inbound workload queueing function for Enterprise Extender (EE) traffic. An additional ancillary input queue (AIQ) is established for inbound traffic for EE if HPR=RTP is specified as a VTAM start option. Each AIQ increases storage utilization by an amount of 36K of fixed ECSA, plus potentially the READSTORAGE value (64K multiplied by the number of SBALs) of fixed CSM 4K data space storage. If you have configured QDIO inbound workload queuing, you must ensure that there is sufficient fixed ECSA and 4K CSM dataspace storage for the AIQ for EE traffic. For additional information regarding storage needs when using WORKLOADQ, see "IP Services: Ensure storage availability for ancillary input queue for Enterprise Extender Traffic" in z/OS Migration.

Back to Top Gathering Documentation (for releases V1R13 and above) If the maintenance listed in this document does not resolve the problem, the following documentation needs to be obtained: 1. D net,CSM,OWNERID=ALL Determines how much storage is being used and by what job/ASID. Issue: D net,CSM without OWNERID to identify current and highwater values for FIXED and ECSA. 2. If the DISPLAY CSM output indicates VTAM owns the storage: Issue: Modify net,TRACE,TYPE=VTAM,MODE=INT,SIZE=4M, OPTION=(CSM,CIO,SMS,PSS,PIU,MSG,SSCP,API,NRM,XBUF,APPC,CIA) NOTE: Do the following if using 8K VIT (MODE=EXT) buffering, as an alternative to specifying MODE=INT: Specify BFRNUM to 10. Ensure you only specify FE1,FEF,FF1 GTF options. Ensure large enough BLOCKSIZE is specified for GTF (IEFRDER DD BLKSIZE defined to at least 8K-details in OW26052) 3. If the DISPLAY CSM output indicates TCPIP owns the storage: TRACE CT,64M,COMP=SYSTCPIP,SUB=(TCPIP) R xx,options=(STORAGE,VTAM,VTAMDATA,MESSAGE,INTERNET,TCP),END 4. Turn on CSM MONITOR function F net,CSM,MONITOR=YES If possible, let the monitor function run for a period of time during which storage growth occurs before taking the dump mentioned in step 5. 5. For releases beginning with V1R13, dump VTAM, TCP/IP, and the CSM dataspaces using a dump command similar to the following: DUMP COMM=(csm storage growth) R xx,JOBNAME=(net,tcpipprocname),SDATA=(SQA,LSQA,CSA,RGN,TRT,NUC),CONT R xx,DSPNAME=(1.CSM*),END For releases prior to V1R13, dump VTAM, TCPIP, their dataspaces and the CSM dataspaces using a dump command similar to the following: DUMP COMM=(csm storage growth) R xx,JOBNAME=(net,tcpipprocname),SDATA=(SQA,LSQA,CSA,RGN,TRT,NUC),CONT R xx,DSPNAME=('net'.ISTITDS1,'tcpipprocname'.*,1.CSM*),END ADDITIONAL NOTE: Please reference technote # 1159164 for additional important information regarding a storage shortage when TCP devices have invalid MVS MIH values.

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