From 6438b3b4c154ea139e3c693f8a6abdd7d7b7ba04 Mon Sep 17 00:00:00 2001 From: Eliza Weisman Date: Wed, 9 Aug 2023 11:43:15 -0700 Subject: [PATCH] proxy: v2.203.2 In 2.13, the default inbound and outbound HTTP request queue capacity decreased from 10,000 requests to 100 requests (in PR #2078). This change results in proxies shedding load much more aggressively while under high load to a single destination service, resulting in increased error rates in comparison to 2.12 (see linkerd/linkerd2#11055 for details). This commit changes the default HTTP request queue capacities for the inbound and outbound proxies back to 10,000 requests, the way they were in 2.12 and earlier. In manual load testing I've verified that increasing the queue capacity results in a substantial decrease in 503 Service Unavailable errors emitted by the proxy: with a queue capacity of 100 requests, the load test described [here] observed a failure rate of 51.51% of requests, while with a queue capacity of 10,000 requests, the same load test observes no failures. Note that I did not modify the TCP connection queue capacities, or the control plane request queue capacity. These were previously configured by the same variable before #2078, but were split out into separate vars in that change. I don't think the queue capacity limits for TCP connection establishment or for control plane requests are currently resulting in instability the way the decreased request queue capacity is, so I decided to make a more focused change to just the HTTP request queues for the proxies. [here]: https://github.com/linkerd/linkerd2/issues/11055#issuecomment-1650957357 --- * Increase HTTP request queue capacity (linkerd/linkerd2-proxy#2449) --- .proxy-version | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/.proxy-version b/.proxy-version index fcc2d18557739..cfecced45b49c 100644 --- a/.proxy-version +++ b/.proxy-version @@ -1 +1 @@ -v2.203.1 +v2.203.2