From 4673dd6d295029016e5a7fa7fcedac93e14402dc Mon Sep 17 00:00:00 2001
From: Conrad Ludgate <conradludgate@gmail.com>
Date: Thu, 3 Oct 2024 14:54:10 +0100
Subject: [PATCH] set thp:never during build

---
 Dockerfile             | 1 +
 proxy/src/bin/proxy.rs | 2 +-
 proxy/src/jemalloc.rs  | 9 ++++++---
 3 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/Dockerfile b/Dockerfile
index bdb76a4f4f..eeb5864cb6 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -42,6 +42,7 @@ COPY --from=pg-build /home/nonroot/pg_install/v17/lib                       pg_i
 COPY --chown=nonroot . .
 
 ARG ADDITIONAL_RUSTFLAGS
+ENV _RJEM_MALLOC_CONF="thp:never"
 RUN set -e \
     && PQ_LIB_DIR=$(pwd)/pg_install/v${STABLE_PG_VERSION}/lib RUSTFLAGS="-Clinker=clang -Clink-arg=-fuse-ld=mold -Clink-arg=-Wl,--no-rosegment ${ADDITIONAL_RUSTFLAGS}" cargo build \
       --bin pg_sni_router  \
diff --git a/proxy/src/bin/proxy.rs b/proxy/src/bin/proxy.rs
index a555c3e586..90fc3de56d 100644
--- a/proxy/src/bin/proxy.rs
+++ b/proxy/src/bin/proxy.rs
@@ -297,7 +297,7 @@ async fn main() -> anyhow::Result<()> {
         build_tag: BUILD_TAG,
     });
 
-    proxy::jemalloc::disable_thp()?;
+    proxy::jemalloc::inspect_thp()?;
     let jemalloc = match proxy::jemalloc::MetricRecorder::new() {
         Ok(t) => Some(t),
         Err(e) => {
diff --git a/proxy/src/jemalloc.rs b/proxy/src/jemalloc.rs
index 4548caf70b..cb3c4ca42f 100644
--- a/proxy/src/jemalloc.rs
+++ b/proxy/src/jemalloc.rs
@@ -10,6 +10,7 @@ use measured::{
     LabelGroup, MetricGroup,
 };
 use tikv_jemalloc_ctl::{config, epoch, epoch_mib, stats, version, Access, AsName, Name};
+use tracing::info;
 
 pub struct MetricRecorder {
     epoch: epoch_mib,
@@ -115,7 +116,9 @@ jemalloc_gauge!(metadata, metadata_mib);
 jemalloc_gauge!(resident, resident_mib);
 jemalloc_gauge!(retained, retained_mib);
 
-pub fn disable_thp() -> Result<(), tikv_jemalloc_ctl::Error> {
-    let opt_thp: &Name = "opt.thp".name();
-    opt_thp.write("never")
+pub fn inspect_thp() -> Result<(), tikv_jemalloc_ctl::Error> {
+    let opt_thp: &Name = c"opt.thp".to_bytes_with_nul().name();
+    let s: &str = opt_thp.read()?;
+    info!("jemalloc opt.thp {s}");
+    Ok(())
 }