A fix is available
APAR status
Closed as program error.
Error description
You are using CICS Web Services, without SSL or IPIC involvement. You notice delays for small packets being sent out by TCP/IP. TCPIP's use of the Nagle algorithm is adding unnecessary delays and causing performance issues in CICS. There is no way for you to specify 'TCP_NODELAY' to override the default behavior. . Additional Symptom(s) Search Keyword(s): socket wait delay Nagel RFC 896 getsockopt setsockopt NODELAY ACK NODELAYACKS . KIXREVNDB
Local fix
Problem summary
**************************************************************** * USERS AFFECTED: All CICS users. * **************************************************************** * PROBLEM DESCRIPTION: Performance degradation may occur when * * sockets domain sends messages using * * TCPIP. * **************************************************************** * RECOMMENDATION: * **************************************************************** By default, TCPIP uses the Nagle algorithm for all data sent over a socket. This can lead to delays in the delivery of network messages. CICS already disabled the Nagle algorithm when sending response data using the IPIC protocol and when using the secure sockets layer. The reported problem showed the delays can have a noticeable impact for other TCPIP environments.
Problem conclusion
DFHSOLS and DFHSOS10 are changed to set the TCPIP TCP_NODELAY option and disable the Nagle algorithm for all CICS sockets domain sockets.
Temporary fix
FIX AVAILABLE BY PTF ONLY
Comments
APAR Information
APAR number
PM06264
Reported component name
CICS TS Z/OS V4
Reported component ID
5655S9700
Reported release
600
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2010-01-29
Closed date
2010-03-03
Last modified date
2010-04-03
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
UK54929
Modules/Macros
DESSOLS DESSOSO DFHSOLS DFHSOSOC DFHSOS00 DFHSOS01 DFHSOS02 DFHSOS03 DFHSOS04 DFHSOS05 DFHSOS06 DFHSOS07 DFHSOS08 DFHSOS09 DFHSOS10 DFHSOS11 DFHSOS12 DFHSOS13 DFHSOS14 DFHSOS15 DFHSOS16 DFHSOS17 DFHSOS18 DFHSOS19 DFHSOS20 DFHSOS21 DFHSOS22 DFHSOS23
Fix information
Fixed component name
CICS TS Z/OS V4
Fixed component ID
5655S9700
Applicable component levels
R600 PSY UK54929
UP10/03/12 P F003
Fix is available
Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.
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Document Information
Modified date:
24 October 2021