Reduce default dns cache ttl to ten seconds (from twenty) (#1636)

Reduce default dns cache ttl to ten seconds (from twenty) to follow address changes more quickly
palantir · Apr 30, 2024 · 93eb3d9 · 93eb3d9
1 parent 7106e12
commit 93eb3d9
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Showing 3 changed files with 14 additions and 7 deletions.
diff --git a/changelog/@unreleased/pr-1636.v2.yml b/changelog/@unreleased/pr-1636.v2.yml
@@ -0,0 +1,6 @@
+type: improvement
+improvement:
+  description: Reduce default dns cache ttl to ten seconds (from twenty) to follow
+    address changes more quickly
+  links:
+  - https://github.com/palantir/sls-packaging/pull/1636
diff --git a/gradle-sls-packaging/src/main/java/com/palantir/gradle/dist/service/tasks/LaunchConfig.java b/gradle-sls-packaging/src/main/java/com/palantir/gradle/dist/service/tasks/LaunchConfig.java
@@ -71,9 +71,10 @@ public final class LaunchConfig {
             "-Djava.io.tmpdir=var/data/tmp",
             "-XX:ErrorFile=var/log/hs_err_pid%p.log",
             "-XX:HeapDumpPath=var/log",
-            // Set DNS cache TTL to 20s to account for systems such as RDS and other
+            // Set DNS cache TTL to 10s to account for systems such as RDS and other
             // AWS-managed systems that modify DNS records on failover.
-            "-Dsun.net.inetaddr.ttl=20",
+            // We use a 10 second value matching the default negative cache ttl.
+            "-Dsun.net.inetaddr.ttl=10",
             "-XX:+UnlockDiagnosticVMOptions",
             "-XX:+IgnoreUnrecognizedVMOptions",
             "-XX:NativeMemoryTracking=summary",

diff --git a/...rc/test/groovy/com/palantir/gradle/dist/service/JavaServiceDistributionPluginTests.groovy b/...rc/test/groovy/com/palantir/gradle/dist/service/JavaServiceDistributionPluginTests.groovy
@@ -457,7 +457,7 @@ class JavaServiceDistributionPluginTests extends GradleIntegrationSpec {
                         '-Djava.io.tmpdir=var/data/tmp',
                         '-XX:ErrorFile=var/log/hs_err_pid%p.log',
                         '-XX:HeapDumpPath=var/log',
-                        '-Dsun.net.inetaddr.ttl=20',
+                        '-Dsun.net.inetaddr.ttl=10',
                         '-XX:+UnlockDiagnosticVMOptions',
                         '-XX:+IgnoreUnrecognizedVMOptions',
                         '-XX:NativeMemoryTracking=summary',
@@ -487,7 +487,7 @@ class JavaServiceDistributionPluginTests extends GradleIntegrationSpec {
                         '-Djava.io.tmpdir=var/data/tmp',
                         '-XX:ErrorFile=var/log/hs_err_pid%p.log',
                         '-XX:HeapDumpPath=var/log',
-                        '-Dsun.net.inetaddr.ttl=20',
+                        '-Dsun.net.inetaddr.ttl=10',
                         '-XX:+UnlockDiagnosticVMOptions',
                         '-XX:+IgnoreUnrecognizedVMOptions',
                         '-XX:NativeMemoryTracking=summary',
@@ -539,7 +539,7 @@ class JavaServiceDistributionPluginTests extends GradleIntegrationSpec {
                         '-Djava.io.tmpdir=var/data/tmp',
                         '-XX:ErrorFile=var/log/hs_err_pid%p.log',
                         '-XX:HeapDumpPath=var/log',
-                        '-Dsun.net.inetaddr.ttl=20',
+                        '-Dsun.net.inetaddr.ttl=10',
                         '-XX:+UnlockDiagnosticVMOptions',
                         '-XX:+IgnoreUnrecognizedVMOptions',
                         '-XX:NativeMemoryTracking=summary',
@@ -569,7 +569,7 @@ class JavaServiceDistributionPluginTests extends GradleIntegrationSpec {
                         '-Djava.io.tmpdir=var/data/tmp',
                         '-XX:ErrorFile=var/log/hs_err_pid%p.log',
                         '-XX:HeapDumpPath=var/log',
-                        '-Dsun.net.inetaddr.ttl=20',
+                        '-Dsun.net.inetaddr.ttl=10',
                         '-XX:+UnlockDiagnosticVMOptions',
                         '-XX:+IgnoreUnrecognizedVMOptions',
                         '-XX:NativeMemoryTracking=summary',
@@ -612,7 +612,7 @@ class JavaServiceDistributionPluginTests extends GradleIntegrationSpec {
                 '-Djava.io.tmpdir=var/data/tmp',
                 '-XX:ErrorFile=var/log/hs_err_pid%p.log',
                 '-XX:HeapDumpPath=var/log',
-                '-Dsun.net.inetaddr.ttl=20',
+                '-Dsun.net.inetaddr.ttl=10',
                 '-XX:+UnlockDiagnosticVMOptions',
                 '-XX:+IgnoreUnrecognizedVMOptions',
                 '-XX:NativeMemoryTracking=summary',