TLA Line data Source code
1 : //! We re-export those from prometheus crate to
2 : //! make sure that we use the same dep version everywhere.
3 : //! Otherwise, we might not see all metrics registered via
4 : //! a default registry.
5 : #![deny(clippy::undocumented_unsafe_blocks)]
6 :
7 : use once_cell::sync::Lazy;
8 : use prometheus::core::{
9 : Atomic, AtomicU64, Collector, GenericCounter, GenericCounterVec, GenericGauge, GenericGaugeVec,
10 : };
11 : pub use prometheus::opts;
12 : pub use prometheus::register;
13 : pub use prometheus::Error;
14 : pub use prometheus::{core, default_registry, proto};
15 : pub use prometheus::{exponential_buckets, linear_buckets};
16 : pub use prometheus::{register_counter_vec, Counter, CounterVec};
17 : pub use prometheus::{register_gauge, Gauge};
18 : pub use prometheus::{register_gauge_vec, GaugeVec};
19 : pub use prometheus::{register_histogram, Histogram};
20 : pub use prometheus::{register_histogram_vec, HistogramVec};
21 : pub use prometheus::{register_int_counter, IntCounter};
22 : pub use prometheus::{register_int_counter_vec, IntCounterVec};
23 : pub use prometheus::{register_int_gauge, IntGauge};
24 : pub use prometheus::{register_int_gauge_vec, IntGaugeVec};
25 : pub use prometheus::{Encoder, TextEncoder};
26 : use prometheus::{Registry, Result};
27 :
28 : pub mod launch_timestamp;
29 : mod wrappers;
30 : pub use wrappers::{CountedReader, CountedWriter};
31 : pub mod metric_vec_duration;
32 :
33 : pub type UIntGauge = GenericGauge<AtomicU64>;
34 : pub type UIntGaugeVec = GenericGaugeVec<AtomicU64>;
35 :
36 : #[macro_export]
37 : macro_rules! register_uint_gauge_vec {
38 : ($NAME:expr, $HELP:expr, $LABELS_NAMES:expr $(,)?) => {{
39 : let gauge_vec = UIntGaugeVec::new($crate::opts!($NAME, $HELP), $LABELS_NAMES).unwrap();
40 : $crate::register(Box::new(gauge_vec.clone())).map(|_| gauge_vec)
41 : }};
42 : }
43 :
44 : #[macro_export]
45 : macro_rules! register_uint_gauge {
46 : ($NAME:expr, $HELP:expr $(,)?) => {{
47 : let gauge = $crate::UIntGauge::new($NAME, $HELP).unwrap();
48 : $crate::register(Box::new(gauge.clone())).map(|_| gauge)
49 : }};
50 : }
51 :
52 : /// Special internal registry, to collect metrics independently from the default registry.
53 : /// Was introduced to fix deadlock with lazy registration of metrics in the default registry.
54 : static INTERNAL_REGISTRY: Lazy<Registry> = Lazy::new(Registry::new);
55 :
56 : /// Register a collector in the internal registry. MUST be called before the first call to `gather()`.
57 : /// Otherwise, we can have a deadlock in the `gather()` call, trying to register a new collector
58 : /// while holding the lock.
59 CBC 485 : pub fn register_internal(c: Box<dyn Collector>) -> Result<()> {
60 485 : INTERNAL_REGISTRY.register(c)
61 485 : }
62 :
63 : /// Gathers all Prometheus metrics and records the I/O stats just before that.
64 : ///
65 : /// Metrics gathering is a relatively simple and standalone operation, so
66 : /// it might be fine to do it this way to keep things simple.
67 1161 : pub fn gather() -> Vec<prometheus::proto::MetricFamily> {
68 1161 : update_rusage_metrics();
69 1161 : let mut mfs = prometheus::gather();
70 1161 : let mut internal_mfs = INTERNAL_REGISTRY.gather();
71 1161 : mfs.append(&mut internal_mfs);
72 1161 : mfs
73 1161 : }
74 :
75 367 : static DISK_IO_BYTES: Lazy<IntGaugeVec> = Lazy::new(|| {
76 367 : register_int_gauge_vec!(
77 367 : "libmetrics_disk_io_bytes_total",
78 367 : "Bytes written and read from disk, grouped by the operation (read|write)",
79 367 : &["io_operation"]
80 367 : )
81 367 : .expect("Failed to register disk i/o bytes int gauge vec")
82 367 : });
83 :
84 367 : static MAXRSS_KB: Lazy<IntGauge> = Lazy::new(|| {
85 367 : register_int_gauge!(
86 367 : "libmetrics_maxrss_kb",
87 367 : "Memory usage (Maximum Resident Set Size)"
88 367 : )
89 367 : .expect("Failed to register maxrss_kb int gauge")
90 367 : });
91 :
92 : pub const DISK_WRITE_SECONDS_BUCKETS: &[f64] = &[
93 : 0.000_050, 0.000_100, 0.000_500, 0.001, 0.003, 0.005, 0.01, 0.05, 0.1, 0.3, 0.5,
94 : ];
95 :
96 1400 : pub fn set_build_info_metric(revision: &str, build_tag: &str) {
97 1400 : let metric = register_int_gauge_vec!(
98 1400 : "libmetrics_build_info",
99 1400 : "Build/version information",
100 1400 : &["revision", "build_tag"]
101 1400 : )
102 1400 : .expect("Failed to register build info metric");
103 1400 : metric.with_label_values(&[revision, build_tag]).set(1);
104 1400 : }
105 :
106 : // Records I/O stats in a "cross-platform" way.
107 : // Compiles both on macOS and Linux, but current macOS implementation always returns 0 as values for I/O stats.
108 : // An alternative is to read procfs (`/proc/[pid]/io`) which does not work under macOS at all, hence abandoned.
109 : //
110 : // Uses https://www.freebsd.org/cgi/man.cgi?query=getrusage to retrieve the number of block operations
111 : // performed by the process.
112 : // We know the size of the block, so we can determine the I/O bytes out of it.
113 : // The value might be not 100% exact, but should be fine for Prometheus metrics in this case.
114 : #[allow(clippy::unnecessary_cast)]
115 1161 : fn update_rusage_metrics() {
116 1161 : let rusage_stats = get_rusage_stats();
117 1161 :
118 1161 : const BYTES_IN_BLOCK: i64 = 512;
119 1161 : DISK_IO_BYTES
120 1161 : .with_label_values(&["read"])
121 1161 : .set(rusage_stats.ru_inblock * BYTES_IN_BLOCK);
122 1161 : DISK_IO_BYTES
123 1161 : .with_label_values(&["write"])
124 1161 : .set(rusage_stats.ru_oublock * BYTES_IN_BLOCK);
125 1161 : MAXRSS_KB.set(rusage_stats.ru_maxrss);
126 1161 : }
127 :
128 1161 : fn get_rusage_stats() -> libc::rusage {
129 1161 : let mut rusage = std::mem::MaybeUninit::uninit();
130 1161 :
131 1161 : // SAFETY: kernel will initialize the struct for us
132 1161 : unsafe {
133 1161 : let ret = libc::getrusage(libc::RUSAGE_SELF, rusage.as_mut_ptr());
134 1161 : assert!(ret == 0, "getrusage failed: bad args");
135 1161 : rusage.assume_init()
136 1161 : }
137 1161 : }
138 :
139 : /// Create an [`IntCounterPairVec`] and registers to default registry.
140 : #[macro_export(local_inner_macros)]
141 : macro_rules! register_int_counter_pair_vec {
142 : ($NAME1:expr, $HELP1:expr, $NAME2:expr, $HELP2:expr, $LABELS_NAMES:expr $(,)?) => {{
143 : match (
144 : $crate::register_int_counter_vec!($NAME1, $HELP1, $LABELS_NAMES),
145 : $crate::register_int_counter_vec!($NAME2, $HELP2, $LABELS_NAMES),
146 : ) {
147 : (Ok(inc), Ok(dec)) => Ok($crate::IntCounterPairVec::new(inc, dec)),
148 : (Err(e), _) | (_, Err(e)) => Err(e),
149 : }
150 : }};
151 : }
152 : /// Create an [`IntCounterPair`] and registers to default registry.
153 : #[macro_export(local_inner_macros)]
154 : macro_rules! register_int_counter_pair {
155 : ($NAME1:expr, $HELP1:expr, $NAME2:expr, $HELP2:expr $(,)?) => {{
156 : match (
157 : $crate::register_int_counter!($NAME1, $HELP1),
158 : $crate::register_int_counter!($NAME2, $HELP2),
159 : ) {
160 : (Ok(inc), Ok(dec)) => Ok($crate::IntCounterPair::new(inc, dec)),
161 : (Err(e), _) | (_, Err(e)) => Err(e),
162 : }
163 : }};
164 : }
165 :
166 : /// A Pair of [`GenericCounterVec`]s. Like an [`GenericGaugeVec`] but will always observe changes
167 : pub struct GenericCounterPairVec<P: Atomic> {
168 : inc: GenericCounterVec<P>,
169 : dec: GenericCounterVec<P>,
170 : }
171 :
172 : /// A Pair of [`GenericCounter`]s. Like an [`GenericGauge`] but will always observe changes
173 : pub struct GenericCounterPair<P: Atomic> {
174 : inc: GenericCounter<P>,
175 : dec: GenericCounter<P>,
176 : }
177 :
178 : impl<P: Atomic> GenericCounterPairVec<P> {
179 927 : pub fn new(inc: GenericCounterVec<P>, dec: GenericCounterVec<P>) -> Self {
180 927 : Self { inc, dec }
181 927 : }
182 :
183 : /// `get_metric_with_label_values` returns the [`GenericCounterPair<P>`] for the given slice
184 : /// of label values (same order as the VariableLabels in Desc). If that combination of
185 : /// label values is accessed for the first time, a new [`GenericCounterPair<P>`] is created.
186 : ///
187 : /// An error is returned if the number of label values is not the same as the
188 : /// number of VariableLabels in Desc.
189 6046 : pub fn get_metric_with_label_values(&self, vals: &[&str]) -> Result<GenericCounterPair<P>> {
190 6046 : Ok(GenericCounterPair {
191 6046 : inc: self.inc.get_metric_with_label_values(vals)?,
192 6046 : dec: self.dec.get_metric_with_label_values(vals)?,
193 : })
194 6046 : }
195 :
196 : /// `with_label_values` works as `get_metric_with_label_values`, but panics if an error
197 : /// occurs.
198 6046 : pub fn with_label_values(&self, vals: &[&str]) -> GenericCounterPair<P> {
199 6046 : self.get_metric_with_label_values(vals).unwrap()
200 6046 : }
201 : }
202 :
203 : impl<P: Atomic> GenericCounterPair<P> {
204 7 : pub fn new(inc: GenericCounter<P>, dec: GenericCounter<P>) -> Self {
205 7 : Self { inc, dec }
206 7 : }
207 :
208 : /// Increment the gauge by 1, returning a guard that decrements by 1 on drop.
209 6053 : pub fn guard(&self) -> GenericCounterPairGuard<P> {
210 6053 : self.inc.inc();
211 6053 : GenericCounterPairGuard(self.dec.clone())
212 6053 : }
213 :
214 : /// Increment the gauge by n, returning a guard that decrements by n on drop.
215 UBC 0 : pub fn guard_by(&self, n: P::T) -> GenericCounterPairGuardBy<P> {
216 0 : self.inc.inc_by(n);
217 0 : GenericCounterPairGuardBy(self.dec.clone(), n)
218 0 : }
219 :
220 : /// Increase the gauge by 1.
221 : #[inline]
222 0 : pub fn inc(&self) {
223 0 : self.inc.inc();
224 0 : }
225 :
226 : /// Decrease the gauge by 1.
227 : #[inline]
228 0 : pub fn dec(&self) {
229 0 : self.dec.inc();
230 0 : }
231 :
232 : /// Add the given value to the gauge. (The value can be
233 : /// negative, resulting in a decrement of the gauge.)
234 : #[inline]
235 0 : pub fn inc_by(&self, v: P::T) {
236 0 : self.inc.inc_by(v);
237 0 : }
238 :
239 : /// Subtract the given value from the gauge. (The value can be
240 : /// negative, resulting in an increment of the gauge.)
241 : #[inline]
242 0 : pub fn dec_by(&self, v: P::T) {
243 0 : self.dec.inc_by(v);
244 0 : }
245 : }
246 :
247 : /// Guard returned by [`GenericCounterPair::guard`]
248 : pub struct GenericCounterPairGuard<P: Atomic>(GenericCounter<P>);
249 :
250 : impl<P: Atomic> Drop for GenericCounterPairGuard<P> {
251 CBC 5663 : fn drop(&mut self) {
252 5663 : self.0.inc();
253 5663 : }
254 : }
255 : /// Guard returned by [`GenericCounterPair::guard_by`]
256 : pub struct GenericCounterPairGuardBy<P: Atomic>(GenericCounter<P>, P::T);
257 :
258 : impl<P: Atomic> Drop for GenericCounterPairGuardBy<P> {
259 UBC 0 : fn drop(&mut self) {
260 0 : self.0.inc_by(self.1);
261 0 : }
262 : }
263 :
264 : /// A Pair of [`IntCounterVec`]s. Like an [`IntGaugeVec`] but will always observe changes
265 : pub type IntCounterPairVec = GenericCounterPairVec<AtomicU64>;
266 :
267 : /// A Pair of [`IntCounter`]s. Like an [`IntGauge`] but will always observe changes
268 : pub type IntCounterPair = GenericCounterPair<AtomicU64>;
269 :
270 : /// A guard for [`IntCounterPair`] that will decrement the gauge on drop
271 : pub type IntCounterPairGuard = GenericCounterPairGuard<AtomicU64>;
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