feat: optional dial9 Tokio telemetry behind a dial9 feature (#10442)

* Add optional dial9 Tokio telemetry behind a `dial9` feature

Integrate dial9 so storage runtimes can emit production-friendly Tokio
traces. Recording is off unless the crate is built with `--features dial9`
and DIAL9_ENABLED=true is set at runtime; with the feature off, runtime
construction is byte-for-byte unchanged.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Y7X6MkjY3P7wpP2MfHdTDY

* Enable dial9 CPU and schedule profiling

Turn on cpu-profiling and sched events behind the same `dial9` feature,
add the DIAL9_CPU_* / DIAL9_SCHEDULE_* env knobs, and document the frame
pointer rustflags the stack unwinder needs.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Y7X6MkjY3P7wpP2MfHdTDY

* Harden dial9 env parsing and the writer-failure path

- Reset Cargo.lock to the branch point and re-resolve, so the diff is
  additive instead of re-resolving unrelated packages. This drops the
  heck 0.5.0 -> 0.4.1 downgrade, which sat in the default build graph and
  would have changed proto codegen identifier casing. The remaining
  non-additive entry, toml_parser 1.0.9 -> 1.1.3, is forced by
  proc-macro-crate via dial9-trace-format-derive.
- Parse DIAL9_* booleans the way dial9 does, accepting 1/y/yes/on and
  0/n/no/off and warning on anything else. `str::parse::<bool>` took only
  exact lowercase true/false, so DIAL9_CPU_PROFILE_ENABLED=0 silently left
  99 Hz sampling on and DIAL9_ENABLED=1 silently left recording off.
- Require the numeric knobs to be positive. A zero disk budget made dial9
  evict everything and stop recording within seconds while the log still
  reported telemetry enabled.
- Treat a set-but-empty DIAL9_TRACE_DIR as unset. It skipped the /tmp
  fallback and wrote up to the full budget into the working directory,
  which is /qdrant next to storage/ in the official image.
- Return a disabled guard as soon as the trace writer fails, before
  with_cpu_profiling and with_sched_events run. Those start their profilers
  eagerly, opening a perf event per thread and installing a process-global
  signal handler that build() would then discard.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Y7X6MkjY3P7wpP2MfHdTDY

* Correct the dial9 docs and give them their own section

- `--cfg tokio_unstable` is required for any task data at all, not merely
  for fuller coverage: dial9's poll, spawn and terminate hooks are all
  `#[cfg(tokio_unstable)]`, and nothing in the repo sets the flag. Without
  it there is no task timeline and DIAL9_TASK_TRACKING_ENABLED does nothing.
- Document `-C debuginfo=2`. `[profile.perf]` inherits `release` and sets no
  `debug` key, so the documented build symbolized off the ELF symtab with
  inlined callees collapsed and no file or line, unlike `[profile.bench]`
  which sets `debug = true` for this reason.
- Move the dial9 material out from between the feature list and the prose
  that belongs to it. Those paragraphs describe `tracing` instrumentation
  and read as dial9's when the example is wedged in front of them, which
  points readers at `#[tracing::instrument]` for a tool that records Tokio
  runtime events and no tracing spans.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Y7X6MkjY3P7wpP2MfHdTDY

* Use cfg_select!

---------

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
Co-authored-by: timvisee <tim@visee.me>

Cargo.lock

@@ -2,6 +2,16 @@
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+ "windows-sys 0.61.2",
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+ "rand 0.9.2",
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+
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+ "proc-macro2",
+ "quote",
+ "str_inflector",
+ "syn 2.0.119",
+ "synstructure",
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+
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+[[package]]
+name = "perf-event-data"
+version = "0.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "575828d9d7d205188048eb1508560607a03d21eafdbba47b8cade1736c1c28e1"
+dependencies = [
+ "bitflags 2.11.0",
+ "c-enum",
+ "perf-event-open-sys2",
+]
+
+[[package]]
+name = "perf-event-open-sys2"
+version = "5.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d9c25955321465255e437600b54296983fab1feac2cd0c38958adeb26dbae49e"
+dependencies = [
+ "libc",
+ "memoffset 0.9.1",
+]
+
 [[package]]
 name = "pest"
 version = "2.8.6"
@@ -5129,6 +5562,15 @@ dependencies = [
  "elliptic-curve",
 ]
 
+[[package]]
+name = "proc-macro-crate"
+version = "3.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e67ba7e9b2b56446f1d419b1d807906278ffa1a658a8a5d8a39dcb1f5a78614f"
+dependencies = [
+ "toml_edit",
+]
+
 [[package]]
 name = "proc-macro-error-attr3"
 version = "3.0.2"
@@ -5290,7 +5732,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "03da047801ff44bb6a4d407d4860c05fd70bb81714e6b2f3812603d5b145b042"
 dependencies = [
  "heck 0.5.0",
- "itertools 0.10.5",
+ "itertools 0.14.0",
  "log",
  "multimap",
  "petgraph 0.8.3",
@@ -5337,7 +5779,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b570b25f7617e43d59005d0990ccb79e950a423952cea19671b7a876da390adf"
 dependencies = [
  "anyhow",
- "itertools 0.10.5",
+ "itertools 0.14.0",
  "proc-macro2",
  "quote",
  "syn 2.0.119",
@@ -5701,6 +6143,21 @@ dependencies = [
  "serde_derive",
 ]
 
+[[package]]
+name = "quanta"
+version = "0.12.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f3ab5a9d756f0d97bdc89019bd2e4ea098cf9cde50ee7564dde6b81ccc8f06c7"
+dependencies = [
+ "crossbeam-utils",
+ "libc",
+ "once_cell",
+ "raw-cpuid",
+ "wasi",
+ "web-sys",
+ "winapi",
+]
+
 [[package]]
 name = "quantization"
 version = "0.1.0"
@@ -5828,7 +6285,7 @@ dependencies = [
  "once_cell",
  "socket2",
  "tracing",
- "windows-sys 0.52.0",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
@@ -5858,6 +6315,16 @@ version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dc33ff2d4973d518d823d61aa239014831e521c75da58e3df4840d3f47749d09"
 
+[[package]]
+name = "radix_trie"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c069c179fcdc6a2fe24d8d18305cf085fdbd4f922c041943e203685d6a1c58fd"
+dependencies = [
+ "endian-type",
+ "nibble_vec",
+]
+
 [[package]]
 name = "raft"
 version = "0.7.0"
@@ -5987,6 +6454,33 @@ dependencies = [
  "rand_core 0.9.5",
 ]
 
+[[package]]
+name = "rand_xoshiro"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f703f4665700daf5512dcca5f43afa6af89f09db47fb56be587f80636bda2d41"
+dependencies = [
+ "rand_core 0.9.5",
+]
+
+[[package]]
+name = "rapidhash"
+version = "4.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5da7e78a036ce858e8d55b7e7dc8ba3a88b78350fd2155d3591bbd966b58589e"
+dependencies = [
+ "rustversion",
+]
+
+[[package]]
+name = "raw-cpuid"
+version = "11.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "498cd0dc59d73224351ee52a95fee0f1a617a2eae0e7d9d720cc622c73a54186"
+dependencies = [
+ "bitflags 2.11.0",
+]
+
 [[package]]
 name = "rawpointer"
 version = "0.2.1"
@@ -6322,7 +6816,7 @@ dependencies = [
  "errno",
  "libc",
  "linux-raw-sys 0.4.15",
- "windows-sys 0.52.0",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
@@ -6335,7 +6829,7 @@ dependencies = [
  "errno",
  "libc",
  "linux-raw-sys 0.12.1",
- "windows-sys 0.52.0",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]
@@ -6403,7 +6897,7 @@ dependencies = [
  "security-framework",
  "security-framework-sys",
  "webpki-root-certs",
- "windows-sys 0.52.0",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]
@@ -6901,7 +7395,7 @@ version = "3.22.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8705578779c2b6bd90d84d66eb2e206b708b1a4d7b9f17641b293545bf1c7e46"
 dependencies = [
- "darling",
+ "darling 0.23.0",
  "proc-macro2",
  "quote",
  "syn 2.0.119",
@@ -7102,6 +7596,12 @@ version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8ee5873ec9cce0195efcb7a4e9507a04cd49aec9c83d0389df45b1ef7ba2e649"
 
+[[package]]
+name = "sketches-ddsketch"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0c6f73aeb92d671e0cc4dca167e59b2deb6387c375391bc99ee743f326994a2b"
+
 [[package]]
 name = "slab"
 version = "0.4.12"
@@ -7269,6 +7769,7 @@ dependencies = [
  "collection",
  "common",
  "dashmap",
+ "dial9",
  "env_logger",
  "fs-err",
  "futures",
@@ -7307,6 +7808,16 @@ dependencies = [
  "wal",
 ]
 
+[[package]]
+name = "str_inflector"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ec0b848d5a7695b33ad1be00f84a3c079fe85c9278a325ff9159e6c99cef4ef7"
+dependencies = [
+ "lazy_static",
+ "regex",
+]
+
 [[package]]
 name = "str_stack"
 version = "0.1.0"
@@ -7533,7 +8044,7 @@ dependencies = [
  "getrandom 0.4.2",
  "once_cell",
  "rustix 1.1.4",
- "windows-sys 0.52.0",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]
@@ -7788,7 +8299,7 @@ dependencies = [
  "indexmap 2.14.0",
  "serde_core",
  "serde_spanned",
- "toml_datetime",
+ "toml_datetime 0.7.5+spec-1.1.0",
  "toml_parser",
  "toml_writer",
  "winnow 0.7.15",
@@ -7804,12 +8315,33 @@ dependencies = [
 ]
 
 [[package]]
-name = "toml_parser"
+name = "toml_datetime"
-version = "1.0.9+spec-1.1.0"
+version = "1.1.1+spec-1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "702d4415e08923e7e1ef96cd5727c0dfed80b4d2fa25db9647fe5eb6f7c5a4c4"
+checksum = "3165f65f62e28e0115a00b2ebdd37eb6f3b641855f9d636d3cd4103767159ad7"
 dependencies = [
- "winnow 0.7.15",
+ "serde_core",
+]
+
+[[package]]
+name = "toml_edit"
+version = "0.25.13+spec-1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6975367e4d2ef766d86af01ffad14b622fecc8d4357a998fbc4deb6e9bacaf9b"
+dependencies = [
+ "indexmap 2.14.0",
+ "toml_datetime 1.1.1+spec-1.1.0",
+ "toml_parser",
+ "winnow 1.0.0",
+]
+
+[[package]]
+name = "toml_parser"
+version = "1.1.3+spec-1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d38ac1cf9b95face32296c0a3ede1fdc270627c9d9c02a7274dd6d960dc4d56"
+dependencies = [
+ "winnow 1.0.0",
 ]
 
 [[package]]
@@ -8162,6 +8694,16 @@ dependencies = [
  "tonic-prost-build",
 ]
 
+[[package]]
+name = "ulid"
+version = "1.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "470dbf6591da1b39d43c14523b2b469c86879a53e8b758c8e090a470fe7b1fbe"
+dependencies = [
+ "rand 0.9.2",
+ "web-time",
+]
+
 [[package]]
 name = "unarray"
 version = "0.1.4"
@@ -8459,7 +9001,7 @@ version = "0.20.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "240e4b81c20a1d6d50d1d7265c658dfbd204e8b9ac4d80f3c931f39462196335"
 dependencies = [
- "darling",
+ "darling 0.23.0",
  "proc-macro-error3",
  "proc-macro2",
  "quote",
@@ -8768,7 +9310,7 @@ version = "0.1.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c2a7b1c03c876122aa43f3020e6c3c3ee5c05081c9a00739faf7503aeba10d22"
 dependencies = [
- "windows-sys 0.52.0",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]

Cargo.toml

@@ -31,6 +31,7 @@ console-subscriber = ["tracing", "dep:console-subscriber"]
 tracy = ["tracing-tracy"]
 tracing-tracy = ["tracing", "dep:tracing-tracy"]
 tokio-tracing = ["tokio/tracing"]
+dial9 = ["storage/dial9"]
 stacktrace = ["rstack-self"]
 chaos-testing = []
 data-consistency-check = ["collection/data-consistency-check"]

docs/DEVELOPMENT.md

@@ -245,6 +245,8 @@ that can be enabled with optional features.
   - note, that you'll also have to [pass `--cfg tokio_unstable` arguments to `rustc`][tokio-tracing] to enable this feature
   - this is required (and enabled automatically) by the `console` feature
   - but you can enable it explicitly with the `tracy` feature, to see Tokio traces in [`Tracy`] profiler
+- `dial9` feature enables [dial9](https://github.com/dial9-rs/dial9) Tokio runtime telemetry,
+  see [its own section](#dial9-tokio-runtime-telemetry) below
 
 Qdrant code is **not** instrumented by default, so you'll have to manually add `#[tracing::instrument]` attributes
 on functions and methods that you want to profile.
@@ -279,6 +281,51 @@ fn some_other_function() {
 [`log`]: https://docs.rs/log/latest/log/
 [tracing-log-warning]: https://docs.rs/tracing-log/latest/tracing_log/#caution-mixing-both-conversions
 
+### dial9 (Tokio runtime telemetry)
+
+The `dial9` feature attaches [dial9](https://github.com/dial9-rs/dial9) hooks to Qdrant's storage
+Tokio runtimes (`general`, `update`, `search-cpu`, `search-io`) and records worker, task and poll
+events, with optional CPU and schedule profiling. Unlike [`tracing`] it needs no `#[instrument]`
+attributes: it observes the runtime rather than your code, and it does *not* pick up [`tracing`]
+spans.
+
+Recording needs both the feature at build time and `DIAL9_ENABLED=true` at run time. With the
+feature off, runtime construction is unchanged.
+
+Three rustflags matter, and none of them is set anywhere in the repo:
+
+- `--cfg tokio_unstable` is **required for any task data at all**, not just for fuller coverage.
+  dial9's poll, spawn and terminate hooks are all `#[cfg(tokio_unstable)]`, so without it a trace
+  carries worker park/unpark and runtime metrics only, with no task timeline, and
+  `DIAL9_TASK_TRACKING_ENABLED` is a silent no-op.
+- `-C force-frame-pointers=yes` lets the CPU and schedule profilers unwind.
+- `-C debuginfo=2` lets those frames symbolize. `[profile.perf]` inherits `release` and sets no
+  `debug` key, so without it the symbolizer falls back to the ELF symtab: inlined callees collapse
+  into their caller and frames carry no file or line.
+
+```console
+# Build with dial9 support (perf profile: release opts, no LTO)
+$ RUSTFLAGS='--cfg tokio_unstable -C force-frame-pointers=yes -C debuginfo=2' \
+    cargo build --profile perf --features dial9
+
+# Run with telemetry + CPU/schedule profiling
+$ DIAL9_ENABLED=true DIAL9_TRACE_DIR=/tmp/qdrant-dial9 ./target/perf/qdrant
+```
+
+Env knobs: `DIAL9_TRACE_DIR` (default `/tmp/dial9-traces`), `DIAL9_MAX_DISK_USAGE_MB`,
+`DIAL9_ROTATION_SECS`, `DIAL9_TASK_TRACKING_ENABLED`, `DIAL9_CPU_PROFILE_ENABLED`,
+`DIAL9_SCHEDULE_PROFILE_ENABLED`, `DIAL9_CPU_SAMPLE_HZ`. Booleans accept `1/true/yes/on` and
+`0/false/no/off`; blank or unrecognized values log a warning and keep the default.
+
+Use a fresh `DIAL9_TRACE_DIR` per run: segments from separate runs in one directory are merged into
+a single trace spanning the gap between them.
+
+View traces with the hosted viewer at <https://dial9-tokio-telemetry.netlify.app/>, or install the
+CLI with `cargo install --locked dial9 --features cli` and run
+`dial9 serve --local-dir $DIAL9_TRACE_DIR`. In the browser, the **Browse** tab is built for dial9's
+S3 key layout and stays empty for a local directory; use the **Raw** tab with an empty prefix, or
+open a segment directly at `viewer.html?trace=trace.0.bin.gz`.
+
 ### Pyroscope (continuous CPU profiling)
 
 Qdrant has built-in [Pyroscope](https://grafana.com/oss/pyroscope/) integration for continuous CPU profiling. Linux only.

lib/storage/Cargo.toml

@@ -14,6 +14,7 @@ workspace = true
 [features]
 tracing = ["dep:tracing", "api/tracing", "collection/tracing", "segment/tracing"]
 staging = ["collection/staging"]
+dial9 = ["dep:dial9"]
 
 [dev-dependencies]
 collection = { path = "../collection", features = ["testing"] }
@@ -70,3 +71,9 @@ async-trait = { workspace = true }
 
 tracing = { workspace = true, optional = true }
 tracing-appender = "0.2"
+
+# Optional Tokio telemetry (https://github.com/dial9-rs/dial9)
+dial9 = { version = "0.5.0", optional = true, default-features = false, features = [
+    "tokio",
+    "cpu-profiling",
+] }

lib/storage/src/content_manager/toc/runtimes.rs

@@ -19,13 +19,26 @@ use tokio::runtime::{self, Runtime};
 /// heavy work runs on the blocking pool, not the async workers.
 const SEARCH_ASYNC_WORKERS: usize = 1;
 
+/// Finish building a runtime, optionally attaching dial9 telemetry hooks.
+fn finish_runtime(builder: runtime::Builder, runtime_name: &str) -> io::Result<Runtime> {
+    cfg_select! {
+        feature = "dial9" => crate::dial9_telemetry::build_runtime(builder, runtime_name),
+        not(feature = "dial9") => {
+            let _ = runtime_name;
+            let mut builder = builder;
+            builder.build()
+        }
+    }
+}
+
 /// Build the CPU-friendly search runtime. Sized for steady-state CPU
 /// saturation: one blocking thread per CPU, so concurrent searches don't
 /// thrash.
 pub(super) fn create_high_cpu_search_runtime(max_search_threads: usize) -> io::Result<Runtime> {
     let blocking_threads = high_cpu_blocking_threads(max_search_threads);
     let async_workers = SEARCH_ASYNC_WORKERS.min(blocking_threads.max(1));
-    runtime::Builder::new_multi_thread()
+    let mut builder = runtime::Builder::new_multi_thread();
+    builder
         .worker_threads(async_workers)
         .max_blocking_threads(blocking_threads)
         .enable_all()
@@ -33,8 +46,8 @@ pub(super) fn create_high_cpu_search_runtime(max_search_threads: usize) -> io::R
             static ATOMIC_ID: AtomicUsize = AtomicUsize::new(0);
             let id = ATOMIC_ID.fetch_add(1, Ordering::SeqCst);
             format!("search-cpu-{id}")
-        })
+        });
-        .build()
+    finish_runtime(builder, "search-cpu")
 }
 
 /// Build the IO-friendly search runtime. Blocking pool size comes from
@@ -43,7 +56,8 @@ pub(super) fn create_high_cpu_search_runtime(max_search_threads: usize) -> io::R
 pub(super) fn create_high_io_search_runtime(max_search_threads: usize) -> io::Result<Runtime> {
     let blocking_threads = high_io_blocking_threads(max_search_threads);
     let async_workers = SEARCH_ASYNC_WORKERS.min(blocking_threads.max(1));
-    runtime::Builder::new_multi_thread()
+    let mut builder = runtime::Builder::new_multi_thread();
+    builder
         .worker_threads(async_workers)
         .max_blocking_threads(blocking_threads)
         .enable_all()
@@ -51,8 +65,8 @@ pub(super) fn create_high_io_search_runtime(max_search_threads: usize) -> io::Re
             static ATOMIC_ID: AtomicUsize = AtomicUsize::new(0);
             let id = ATOMIC_ID.fetch_add(1, Ordering::SeqCst);
             format!("search-io-{id}")
-        })
+        });
-        .build()
+    finish_runtime(builder, "search-io")
 }
 
 pub(super) fn create_update_runtime(max_optimization_threads: usize) -> io::Result<Runtime> {
@@ -70,11 +84,12 @@ pub(super) fn create_update_runtime(max_optimization_threads: usize) -> io::Resu
     if max_optimization_threads > 0 {
         builder.max_blocking_threads(max_optimization_threads);
     }
-    builder.build()
+    finish_runtime(builder, "update")
 }
 
 pub(super) fn create_general_purpose_runtime() -> io::Result<Runtime> {
-    runtime::Builder::new_multi_thread()
+    let mut builder = runtime::Builder::new_multi_thread();
+    builder
         .enable_time()
         .enable_io()
         .worker_threads(max(common::cpu::get_num_cpus(), 2))
@@ -82,8 +97,8 @@ pub(super) fn create_general_purpose_runtime() -> io::Result<Runtime> {
             static ATOMIC_ID: AtomicUsize = AtomicUsize::new(0);
             let id = ATOMIC_ID.fetch_add(1, Ordering::SeqCst);
             format!("general-{id}")
-        })
+        });
-        .build()
+    finish_runtime(builder, "general")
 }
 
 /// Blocking-thread count for the high-CPU search pool.

lib/storage/src/dial9_telemetry.rs

@@ -0,0 +1,216 @@
+//! Optional [dial9](https://github.com/dial9-rs/dial9) Tokio telemetry.
+//!
+//! Enabled at compile time with the `dial9` feature and at runtime with
+//! `DIAL9_ENABLED=true`. When disabled (feature off, or env unset/false),
+//! runtime construction is unchanged and recording is a no-op.
+
+use std::sync::OnceLock;
+use std::time::Duration;
+use std::{env, io};
+
+use dial9::cpu::{CpuProfilingConfig, SchedEventConfig};
+use dial9::{
+    Dial9Handle, Dial9HandleTokioExt, DiskBuffer, Recorder, RecorderPerfExt, TokioAttachOptions,
+    recorder_disabled, recorder_or_disabled,
+};
+use tokio::runtime::{Builder, Runtime};
+
+/// Process-wide dial9 handle for attaching Tokio runtimes.
+static HANDLE: OnceLock<Dial9Handle> = OnceLock::new();
+
+/// Holds the dial9 recorder for the process lifetime.
+///
+/// Constructed by [`init`]. Dropping it (at process shutdown) flushes and
+/// stops the recorder.
+#[derive(Debug)]
+pub struct Dial9Guard {
+    recorder: Option<Recorder>,
+}
+
+impl Drop for Dial9Guard {
+    fn drop(&mut self) {
+        if let Some(recorder) = self.recorder.take() {
+            recorder.graceful_shutdown(Duration::from_secs(5));
+        }
+    }
+}
+
+/// Read a boolean `DIAL9_*` variable.
+///
+/// Matches dial9's own env parsing: trimmed, case-insensitive, and accepting
+/// the usual spellings rather than only `str::parse::<bool>`. A blank or
+/// unrecognized value warns and falls back to `default`, so an operator who
+/// writes `DIAL9_CPU_PROFILE_ENABLED=0` is not silently left with profiling on.
+fn env_bool(name: &str, default: bool) -> bool {
+    let Ok(raw) = env::var(name) else {
+        return default;
+    };
+
+    match raw.trim().to_ascii_lowercase().as_str() {
+        "" => default,
+        "1" | "t" | "true" | "y" | "yes" | "on" => true,
+        "0" | "f" | "false" | "n" | "no" | "off" => false,
+        other => {
+            log::warn!("dial9: ignoring invalid {name}={other:?}, using {default}");
+            default
+        }
+    }
+}
+
+/// Read a `DIAL9_*` variable that dial9 requires to be non-zero.
+///
+/// Zero is rejected rather than passed through: dial9 treats a zero disk budget
+/// as "evict everything" (killing recording seconds after it starts) and fails
+/// outright on a zero rotation period.
+fn env_positive_u64(name: &str, default: u64) -> u64 {
+    let Ok(raw) = env::var(name) else {
+        return default;
+    };
+
+    let raw = raw.trim();
+    if raw.is_empty() {
+        return default;
+    }
+
+    match raw.parse::<u64>() {
+        Ok(value) if value > 0 => value,
+        _ => {
+            log::warn!("dial9: ignoring invalid {name}={raw:?}, using {default}");
+            default
+        }
+    }
+}
+
+/// Read a path-valued `DIAL9_*` variable, treating a blank value as unset.
+///
+/// `env::var` returns `Ok("")` for a variable that is set but empty (a common
+/// shape from `docker run -e VAR` and unset compose interpolations), which dial9
+/// would otherwise resolve to relative paths in the working directory.
+fn env_path(name: &str, default: &str) -> String {
+    match env::var(name) {
+        Ok(raw) if !raw.trim().is_empty() => raw.trim().to_string(),
+        _ => default.to_string(),
+    }
+}
+
+/// Initialize dial9 from `DIAL9_*` environment variables.
+///
+/// Safe to call once at process start, before any Tokio runtimes are built.
+/// Returns a guard that must be kept alive until shutdown.
+///
+/// `application_version` is recorded into every trace segment (e.g. the qdrant
+/// binary version).
+///
+/// Recognized variables (subset of dial9's env surface). Booleans accept
+/// `1/t/true/y/yes/on` and `0/f/false/n/no/off`; blank or unrecognized values
+/// warn and keep the default:
+///
+/// - `DIAL9_ENABLED`: record at all (default: off)
+/// - `DIAL9_TRACE_DIR`: trace directory (default: `/tmp/dial9-traces`)
+/// - `DIAL9_MAX_DISK_USAGE_MB`: total on-disk budget, must be > 0 (default: `1024`)
+/// - `DIAL9_ROTATION_SECS`: segment rotation period, must be > 0 (default: `60`)
+/// - `DIAL9_CPU_PROFILE_ENABLED`: CPU stack sampling (default: on, Linux)
+/// - `DIAL9_CPU_SAMPLE_HZ`: sampling frequency, must be > 0 (default: `99`)
+/// - `DIAL9_SCHEDULE_PROFILE_ENABLED`: sched-switch capture (default: on, Linux)
+pub fn init(application_version: &str) -> Dial9Guard {
+    let enabled = env_bool("DIAL9_ENABLED", false);
+
+    if !enabled {
+        log::info!("dial9 telemetry disabled (set DIAL9_ENABLED=true to enable)");
+        let recorder = recorder_disabled();
+        let _ = HANDLE.set(recorder.handle().clone());
+        return Dial9Guard {
+            recorder: Some(recorder),
+        };
+    }
+
+    let trace_dir = env_path("DIAL9_TRACE_DIR", "/tmp/dial9-traces");
+    let max_disk_mb = env_positive_u64("DIAL9_MAX_DISK_USAGE_MB", 1024);
+    let rotation_secs = env_positive_u64("DIAL9_ROTATION_SECS", 60);
+    let cpu_profile_enabled = env_bool("DIAL9_CPU_PROFILE_ENABLED", cfg!(target_os = "linux"));
+    let schedule_profile_enabled =
+        env_bool("DIAL9_SCHEDULE_PROFILE_ENABLED", cfg!(target_os = "linux"));
+    let cpu_sample_hz = env_positive_u64("DIAL9_CPU_SAMPLE_HZ", 99);
+
+    let writer = DiskBuffer::builder()
+        .base_path(&trace_dir)
+        .max_total_size(max_disk_mb.saturating_mul(1024 * 1024))
+        .rotation_period(Duration::from_secs(rotation_secs))
+        .build();
+
+    if let Err(ref err) = writer {
+        // Return before the profiler setup below. `with_cpu_profiling` and
+        // `with_sched_events` start their profilers immediately (opening a perf
+        // event per thread, and installing a process-global signal handler on
+        // the fallback path), and `build()` would only discard them.
+        log::error!(
+            "dial9: failed to create trace writer at {trace_dir}: {err}; telemetry disabled"
+        );
+        let recorder = recorder_disabled();
+        let _ = HANDLE.set(recorder.handle().clone());
+        return Dial9Guard {
+            recorder: Some(recorder),
+        };
+    }
+
+    let mut builder = recorder_or_disabled(writer).segment_metadata([
+        ("service".to_string(), "qdrant".to_string()),
+        (
+            "application.version".to_string(),
+            application_version.to_string(),
+        ),
+    ]);
+
+    if cpu_profile_enabled {
+        builder =
+            builder.with_cpu_profiling(CpuProfilingConfig::default().frequency_hz(cpu_sample_hz));
+    }
+    if schedule_profile_enabled {
+        builder = builder.with_sched_events(SchedEventConfig::default());
+    }
+
+    let recorder = builder.build();
+
+    if recorder.handle().is_connected() {
+        if let Err(err) = recorder.install_global_handle() {
+            log::warn!("dial9: could not install global handle: {err}");
+        }
+        log::info!(
+            "dial9 telemetry enabled; writing traces to {trace_dir} \
+             (max {max_disk_mb} MiB, rotate every {rotation_secs}s, \
+             cpu_profile={cpu_profile_enabled}, sched_profile={schedule_profile_enabled}, \
+             sample_hz={cpu_sample_hz})"
+        );
+    } else {
+        log::error!(
+            "dial9: recorder not connected after init (trace_dir={trace_dir}); \
+             check DiskBuffer / cpu-profiling permissions; telemetry inactive"
+        );
+    }
+
+    let _ = HANDLE.set(recorder.handle().clone());
+    Dial9Guard {
+        recorder: Some(recorder),
+    }
+}
+
+fn handle() -> Dial9Handle {
+    HANDLE.get().cloned().unwrap_or_else(Dial9Handle::disabled)
+}
+
+/// Build a Tokio runtime, attaching dial9 hooks when telemetry is active.
+pub fn build_runtime(mut builder: Builder, runtime_name: &str) -> io::Result<Runtime> {
+    let handle = handle();
+    if !handle.is_connected() {
+        return builder.build();
+    }
+
+    let task_tracking = env_bool("DIAL9_TASK_TRACKING_ENABLED", true);
+
+    let options = TokioAttachOptions::builder()
+        .runtime_name(runtime_name.to_string())
+        .task_tracking_enabled(task_tracking)
+        .build();
+
+    handle.attach_tokio_runtime(builder, options)
+}

lib/storage/src/lib.rs

@@ -14,6 +14,8 @@ pub mod audit;
 pub mod audit_reader;
 mod common;
 pub mod content_manager;
+#[cfg(feature = "dial9")]
+pub mod dial9_telemetry;
 pub mod dispatcher;
 pub mod issues_subscribers;
 pub mod quota;

src/main.rs

@@ -426,6 +426,14 @@ fn main() -> anyhow::Result<()> {
 
     welcome(&settings);
 
+    //
+    // Optional dial9 Tokio telemetry (compile with `--features dial9`,
+    // enable at runtime with DIAL9_ENABLED=true). Must run before any
+    // TableOfContent Tokio runtimes are constructed.
+    //
+    #[cfg(feature = "dial9")]
+    let _dial9_guard = storage::dial9_telemetry::init(env!("CARGO_PKG_VERSION"));
+
     //
     // Audit logging
     //