A fix is available
APAR status
Closed as program error.
Error description
Performance degradation occurs on 10Gb adapters when the large_receive attribute and IPSEC are enabled. By default, large_receive is enabled on AIX 5.3 TL9 causing this issue to surface after an upgrade. Simple FTP throughput on the 10Gb adapter has been observed at 300Kb/sec and in some cases actually appeared to hang. The work-around for this issue is to turn OFF large_receive, IPSEC or chksum_offload.
Local fix
Problem summary
Performance degradation occurs on 10Gb adapters when the large_receive attribute and IPSEC are enabled.
Problem conclusion
If IPSec is enabled and adapter has already checked the checksum, TCP won't check checksum again and drop the packets due to bad checksum.
Temporary fix
Comments
5300-09 - use AIX APAR IZ65672 5300-10 - use AIX APAR IZ86438 5300-11 - use AIX APAR IZ73544 5300-12 - use AIX APAR IZ91517 6100-03 - use AIX APAR IZ74390 6100-04 - use AIX APAR IZ75548 6100-05 - use AIX APAR IZ90867 6100-06 - use AIX APAR IZ95094 6100-07 - use AIX APAR IZ95224 7100-01 - use AIX APAR IZ99502
APAR Information
APAR number
IZ86438
Reported component name
AIX 5.3
Reported component ID
5765G0300
Reported release
530
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Submitted date
2010-10-11
Closed date
2011-01-04
Last modified date
2013-03-24
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Fixed component name
AIX 5.3
Fixed component ID
5765G0300
Applicable component levels
R530 PSY U838225
UP11/02/23 I 1000
PTF to Fileset Mapping
U838225 bos.net.tcp.client 5.3.10.5
[{"Business Unit":{"code":"BU054","label":"Systems w\/TPS"},"Product":{"code":"SG11P","label":"APARs - AIX 5.3 environment"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"530","Edition":"","Line of Business":{"code":"","label":""}}]
Document Information
Modified date:
24 March 2013