Slow transfer rate to application on OCP 4.14 / RHEL9
Issue
- Cross-cluster data transfer rate is impacted.
- The application specifies a TCP receive socket buffer size.
- TCP advertises a Window scale that is smaller than the socket buffer.
- This did not happen on Red Hat Enterprise Linux 8
Environment
- Red Hat Openshift Container Platform 4.14
- Red Hat Openshift Container Platform 4.16
- Red Hat Openshift Container Platform 4.17
- Red Hat Openshift Container Platform 4.18
- Red Hat Enterprise 9.2 kernel kernel-5.14.0-284.105.1.el9_2
- Red Hat Enterprise 9.4 kernels prior to
kernel-5.14.0-427.65.1.el9_4 - Red Hat Enterprise 9.5 all kernels
- Application sets TCP socket buffer size with
setsockopt(SO_RCVBUF/SO_SENDBUF). - auto-tuned TCP socket buffers that never grow can sometimes benefit from this fix.
Subscriber exclusive content
A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more.
