{"id":1139,"date":"2023-01-21T21:43:35","date_gmt":"2023-01-21T21:43:35","guid":{"rendered":"https:\/\/blog.thomarite.uk\/?p=1139"},"modified":"2023-01-21T21:43:35","modified_gmt":"2023-01-21T21:43:35","slug":"ipv6-big-tcp-replace-tcp-in-dc-homa","status":"publish","type":"post","link":"https:\/\/blog.thomarite.uk\/index.php\/2023\/01\/21\/ipv6-big-tcp-replace-tcp-in-dc-homa\/","title":{"rendered":"IPv6 BIG TCP \/ Replace TCP in DC: Homa"},"content":{"rendered":"\n

This week a colleague pass this link<\/a> about running kubernetes cluster running on Cilium. The interesting point is the high throughput is achieved by BIG TCP and IPv6!<\/p>\n\n\n\n

The summary (copied) is:<\/p>\n\n\n\n

TCP segments in the OS are up to 65K, NIC hardware does the segmentation – we do this now, but the 65K is a limitation of IPv4 addressing.\u00a0 BIG TCP uses IPv6 and allows much large TCP segments within OS currently 512K but theoretically higher.\u00a0 End result – better perf (>20% higher in this video) and latency (2.2x faster through the OS).<\/p>\n\n\n\n

Then I saw this other video<\/a> from John Ousterhout<\/a>. It is similar topic as the Kubernetes video above as K8S is used mainly in datacenters. <\/p>\n\n\n\n

High performance:
– data throughput: full link speed for large messages
– low tail latency: <10us for short messages? (DC)
– message throughput: 100M short messages per second? (DC)<\/p>\n\n\n\n

TCP issues in DC:
1- stream oriented (no load balancing) -> message based
2- connection oriented (can break infiniband!, expensive,)-> connectionless
3- fair scheduling (bw sharing) -> run to completion (SRPT)
4- sender-driven congestion control (based on buffer occupancy) -> receiver- driven congestion control
5- in-order delivery -> no ordering requirements<\/p>\n\n\n\n

As well, it is important the move to NIC (as there is already a lot of NIC offloading).<\/p>\n\n\n\n

His proposal for HOMA looks very nice but I like how he explains how dificult is going to be successful. Still worth trying.<\/p>\n","protected":false},"excerpt":{"rendered":"

This week a colleague pass this link about running kubernetes cluster running on Cilium. The interesting point is the high throughput is achieved by BIG TCP and IPv6! The summary (copied) is: TCP segments in the OS are up to 65K, NIC hardware does the segmentation – we do this now, but the 65K is … Continue reading “IPv6 BIG TCP \/ Replace TCP in DC: Homa”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[27,2],"tags":[],"class_list":["post-1139","post","type-post","status-publish","format-standard","hentry","category-kubernetes","category-networks"],"_links":{"self":[{"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/posts\/1139","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/comments?post=1139"}],"version-history":[{"count":1,"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/posts\/1139\/revisions"}],"predecessor-version":[{"id":1140,"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/posts\/1139\/revisions\/1140"}],"wp:attachment":[{"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/media?parent=1139"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/categories?post=1139"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/tags?post=1139"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}