feat(openshift): Optimize TCP settings for high throughput and low latency#809
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yarda merged 1 commit intoredhat-performance:masterfrom Feb 5, 2026
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…tency Apply specific kernel network tuning parameters to the OpenShift profile (/profiles/openshift/tuned.conf) to support high bandwidth-delay product links. The following TCP settings are added: net.ipv4.tcp_notsent_lowat=131072: Sets tcp_notsent_lowat to a value intended to balance throughput and latency while limiting total socket memory usage. net.ipv4.tcp_slow_start_after_idle=0: Disables slow start after a connection has been idle, allowing immediate maximum throughput upon resuming data transfer. net.ipv4.tcp_rmem="4096 131072 16777216": Increases the maximum TCP receive buffer size to improve performance on high-bandwidth-delay product connections. net.ipv4.tcp_wmem="4096 16384 16777216": Increases the maximum TCP send buffer size for similar reasons. These changes are based on work done by Cloudflare for improving TCP performance on high bandwidth-delay product links but are more conservative in adjusting rmem and wmem Reference: https://blog.cloudflare.com/optimizing-tcp-for-high-throughput-and-low-latency/ Signed-off-by: Graham Heffern <gheffern@gmail.com>
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Thanks, LGTM. It seems the |
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Update network-throughput profile and drop now duplicate tuning from the openshift profile. Follows up the redhat-performance#809 and cleans the things a bit. Signed-off-by: Jaroslav Škarvada <jskarvad@redhat.com>
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Apply specific kernel network tuning parameters to the OpenShift profile (/profiles/openshift/tuned.conf) to support high bandwidth-delay product links.
The following TCP settings are added:
net.ipv4.tcp_notsent_lowat=131072: Sets tcp_notsent_lowat to a value intended to balance throughput and latency while limiting total socket memory usage.
net.ipv4.tcp_slow_start_after_idle=0: Disables slow start after a connection has been idle, allowing immediate maximum throughput upon resuming data transfer.
net.ipv4.tcp_rmem="4096 131072 16777216": Increases the maximum TCP receive buffer size to improve performance on high-bandwidth-delay product connections.
net.ipv4.tcp_wmem="4096 16384 16777216": Increases the maximum TCP send buffer size for similar reasons.
These changes are based on work done by Cloudflare for improving TCP performance on high bandwidth-delay product links but are more conservative in adjusting rmem and wmem
Reference: https://blog.cloudflare.com/optimizing-tcp-for-high-throughput-and-low-latency/