Trim redundant viewer JS and Rust comments (#933)

* Trim redundant viewer JS comments

Remove comments that restate what the adjacent code already says and
decorative section dividers, keeping comments that explain why
(rationale, invariants, workarounds, browser/echarts quirks).
Comments-only change; behavior is identical.

* Trim more redundant viewer JS comments

Follow-up: drop remaining what-only comments and decorative dividers
in the query explorer. Comments-only; behavior unchanged.

* Trim redundant Rust comments

Remove comments that restate what the adjacent code already says and
decorative section dividers, keeping doc comments, SAFETY notes, eBPF
and sampler design rationale, and why-explanations. Comments-only
change; behavior is identical.

* Trim redundant Rust comments in recorder/hindsight/exporter

Drop restate-only comments and banner dividers; keep format
contracts and why-rationale. Comments-only; behavior unchanged.

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: thinkingfish

crates/dashboard/src/dashboard/blockio.rs

@@ -4,10 +4,6 @@ use crate::plot::*;
 pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
     let mut view = View::new(data, sections);
 
-    /*
-     * Operations
-     */
-
     let mut operations = Group::new("Operations", "operations");
 
     let totals = operations.subgroup("Totals");
@@ -48,10 +44,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(operations);
 
-    /*
-     * Latency
-     */
-
     let mut latency = Group::new("Latency", "latency");
 
     let by_op = latency.subgroup("By Operation");
@@ -66,10 +58,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(latency);
 
-    /*
-     * IO Size
-     */
-
     let mut size = Group::new("Size", "size");
 
     let by_op = size.subgroup("By Operation");

crates/dashboard/src/dashboard/cgroups.rs

@@ -26,7 +26,6 @@ fn add_cgroup_metrics(group: &mut Group, individual: bool) {
         }
     };
 
-    // CPU Total Cores
     group.plot_promql(
         PlotOpts::counter(
             "Total CPU Cores",
@@ -36,7 +35,6 @@ fn add_cgroup_metrics(group: &mut Group, individual: bool) {
         format!("{} / 1000000000", rate("cgroup_cpu_usage")),
     );
 
-    // CPU User Cores
     group.plot_promql(
         PlotOpts::counter("User CPU Cores", format!("{prefix}-user-cores"), Unit::Count),
         if individual {
@@ -46,7 +44,6 @@ fn add_cgroup_metrics(group: &mut Group, individual: bool) {
         },
     );
 
-    // CPU System Cores
     group.plot_promql(
         PlotOpts::counter(
             "System CPU Cores",
@@ -60,7 +57,6 @@ fn add_cgroup_metrics(group: &mut Group, individual: bool) {
         },
     );
 
-    // CPU Migrations
     group.plot_promql(
         PlotOpts::counter(
             "CPU Migrations",
@@ -70,7 +66,6 @@ fn add_cgroup_metrics(group: &mut Group, individual: bool) {
         rate("cgroup_cpu_migrations"),
     );
 
-    // CPU Throttled Time
     group.plot_promql(
         PlotOpts::counter(
             "CPU Throttled Time",
@@ -80,7 +75,6 @@ fn add_cgroup_metrics(group: &mut Group, individual: bool) {
         rate("cgroup_cpu_throttled_time"),
     );
 
-    // IPC
     group.plot_promql(
         PlotOpts::counter("IPC", format!("{prefix}-ipc"), Unit::Count),
         if individual {
@@ -90,13 +84,11 @@ fn add_cgroup_metrics(group: &mut Group, individual: bool) {
         },
     );
 
-    // TLB Flushes
     group.plot_promql(
         PlotOpts::counter("TLB Flushes", format!("{prefix}-tlb-flush"), Unit::Rate),
         rate("cgroup_cpu_tlb_flush"),
     );
 
-    // Syscalls
     group.plot_promql(
         PlotOpts::counter("Syscalls", format!("{prefix}-syscall"), Unit::Rate),
         rate("cgroup_syscall"),

crates/dashboard/src/dashboard/cpu.rs

@@ -20,10 +20,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
     let mut view = View::new(data, sections);
     let multi_cpu = has_multiple_cpus(data);
 
-    /*
-     * Utilization
-     */
-
     let mut utilization = Group::new("Utilization", "utilization");
 
     let busy = utilization.subgroup("Total CPU");
@@ -83,10 +79,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(utilization);
 
-    /*
-     * Performance
-     */
-
     let mut performance = Group::new("Performance", "performance");
 
     let ipc = performance.subgroup("Instructions per Cycle");
@@ -166,10 +158,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(performance);
 
-    /*
-     * Branch Prediction
-     */
-
     let mut branch = Group::new("Branch Prediction", "branch-prediction");
 
     let miss = branch.subgroup("Misprediction Rate");
@@ -229,14 +217,8 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(branch);
 
-    /*
-     * DTLB (Data Translation Lookaside Buffer)
-     * cpu_dtlb_miss aggregates all variants:
-     * - unlabeled (AMD/ARM combined)
-     * - op="load" (Intel)
-     * - op="store" (Intel)
-     */
-
+    // cpu_dtlb_miss aggregates all variants: unlabeled (AMD/ARM combined),
+    // op="load" (Intel), op="store" (Intel).
     let mut dtlb = Group::new("DTLB", "dtlb");
 
     let misses = dtlb.subgroup("DTLB Misses");
@@ -278,10 +260,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(dtlb);
 
-    /*
-     * Migrations
-     */
-
     let mut migrations = Group::new("Migrations", "migrations");
 
     let to = migrations.subgroup("Incoming Migrations");
@@ -322,10 +300,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(migrations);
 
-    /*
-     * TLB Flush
-     */
-
     let mut tlb = Group::new("TLB Flush", "tlb-flush");
 
     let total = tlb.subgroup("Total TLB Flushes");

crates/dashboard/src/dashboard/exceptions.rs

@@ -9,10 +9,6 @@ use crate::plot::*;
 pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
     let mut view = View::new(data, sections);
 
-    /*
-     * Network
-     */
-
     let mut network = Group::new("Network", "network");
 
     let drops = network.subgroup("Packet Drops & Transmit Errors");
@@ -31,10 +27,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(network);
 
-    /*
-     * TCP
-     */
-
     let mut tcp = Group::new("TCP", "tcp");
 
     let retransmits = tcp.subgroup("Retransmits");
@@ -49,15 +41,10 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(tcp);
 
-    /*
-     * Cloud (ENA) allowance limits
-     *
-     * AWS surfaces these counters when an instance hits a hardware-enforced
-     * rate limit. The metrics only appear on ENA-equipped hosts — on
-     * everything else the queries resolve to empty series and the panels
-     * stay blank, which is the right behavior.
-     */
-
+    // AWS surfaces these counters when an instance hits a hardware-enforced
+    // rate limit. The metrics only appear on ENA-equipped hosts — on
+    // everything else the queries resolve to empty series and the panels
+    // stay blank, which is the right behavior.
     let mut ena = Group::new("AWS ENA Allowance Exceeded", "ena");
 
     let bw = ena.subgroup("Bandwidth");
@@ -93,10 +80,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(ena);
 
-    /*
-     * CPU throttling
-     */
-
     let mut throttle = Group::new("CPU Throttling", "cpu-throttling");
 
     let events = throttle.subgroup("Throttle Events");
@@ -135,18 +118,13 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(throttle);
 
-    /*
-     * Block IO
-     *
-     * `blockio_errors` is labeled (op, error) where error buckets coarse
-     * blk_status_t classes: io / timeout / nospc / target / protection /
-     * unsupported / other. `blockio_requeues` counts requests the block
-     * layer put back on the queue (driver couldn't complete; SCSI EH or
-     * NVMe controller reset retried under the covers). Pairing them is
-     * diagnostic — high requeues with flat errors means recovery is
-     * absorbing the fault; both rising means real damage.
-     */
-
+    // `blockio_errors` is labeled (op, error) where error buckets coarse
+    // blk_status_t classes: io / timeout / nospc / target / protection /
+    // unsupported / other. `blockio_requeues` counts requests the block
+    // layer put back on the queue (driver couldn't complete; SCSI EH or
+    // NVMe controller reset retried under the covers). Pairing them is
+    // diagnostic — high requeues with flat errors means recovery is
+    // absorbing the fault; both rising means real damage.
     let mut blockio = Group::new("Block IO", "blockio");
 
     let errors = blockio.subgroup("Errors");

crates/dashboard/src/dashboard/gpu.rs

@@ -21,10 +21,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
     let mut view = View::new(data, sections);
     let multi_gpu = has_multiple_gpus(data);
 
-    /*
-     * Utilization
-     */
-
     let mut utilization = Group::new("Utilization", "utilization");
 
     let gpu = utilization.subgroup("GPU Utilization");
@@ -144,10 +140,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(activity);
 
-    /*
-     * Memory
-     */
-
     let mut memory = Group::new("Memory", "memory");
 
     let capacity = memory.subgroup("Capacity");
@@ -214,10 +206,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(memory);
 
-    /*
-     * PCIe
-     */
-
     let mut pcie = Group::new("PCIe", "pcie");
 
     let rx = pcie.subgroup("Receive");
@@ -263,10 +251,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(pcie);
 
-    /*
-     * Power
-     */
-
     let mut power = Group::new("Power", "power");
 
     let draw = power.subgroup("Power Draw");
@@ -297,10 +281,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(power);
 
-    /*
-     * Temperature
-     */
-
     let mut thermal = Group::new("Temperature", "temperature");
 
     let temps = thermal.subgroup("Temperatures");
@@ -324,10 +304,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(thermal);
 
-    /*
-     * Clocks
-     */
-
     let mut clocks = Group::new("Clocks", "clocks");
 
     let freqs = clocks.subgroup("Clock Frequencies");

crates/dashboard/src/dashboard/memory.rs

@@ -4,10 +4,6 @@ use crate::plot::*;
 pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
     let mut view = View::new(data, sections);
 
-    /*
-     * Usage
-     */
-
     let mut usage = Group::new("Usage", "usage");
 
     let capacity = usage.subgroup("Capacity");
@@ -46,10 +42,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(usage);
 
-    /*
-     * NUMA
-     */
-
     let mut numa = Group::new("NUMA", "numa");
 
     let locality = numa.subgroup("Local vs Remote");

crates/dashboard/src/dashboard/network.rs

@@ -4,10 +4,6 @@ use crate::plot::*;
 pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
     let mut view = View::new(data, sections);
 
-    /*
-     * Traffic
-     */
-
     let mut traffic = Group::new("Traffic", "traffic");
 
     let bandwidth = traffic.subgroup("Bandwidth");
@@ -36,10 +32,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(traffic);
 
-    /*
-     * Errors
-     */
-
     let mut errors = Group::new("Errors", "errors");
 
     let health = errors.subgroup("Drops & Retransmits");
@@ -57,10 +49,6 @@ pub fn generate(data: &Tsdb, sections: Vec<Section>) -> View {
 
     view.group(errors);
 
-    /*
-     * TCP
-     */
-
     let mut tcp = Group::new("TCP", "tcp");
 
     let latency = tcp.subgroup("Packet Latency");