optimize zfs

benches/iai.rs

@@ -1,5 +1,7 @@
 use iai::black_box;
 use palantir::get_metrics;
+use palantir::heim::temperatures;
+use palantir::zfs::pools;
 use tokio::runtime::Runtime;
 
 fn iai_get_metrics() -> String {
@@ -7,4 +9,13 @@ fn iai_get_metrics() -> String {
     rt.block_on(async { black_box(get_metrics().await.unwrap()) })
 }
 
-iai::main!(iai_get_metrics);
+fn iai_zfs_pool() {
+    black_box(pools().collect::<Vec<_>>());
+}
+
+fn iai_temperatures() {
+    let rt = Runtime::new().unwrap();
+    rt.block_on(async { black_box(temperatures().await).unwrap() });
+}
+
+iai::main!(iai_get_metrics, iai_zfs_pool, iai_temperatures);

src/lib.rs

@@ -1,27 +1,17 @@
-pub(crate) mod heim;
+pub mod heim;
-mod zfs;
+pub mod zfs;
 
 use crate::heim::*;
 use crate::zfs::pools;
 use color_eyre::Result;
 use futures_util::stream::StreamExt;
 use futures_util::{pin_mut, try_join};
-use std::collections::{HashMap, HashSet};
+use std::collections::HashSet;
 use std::fmt::Write;
 
 pub async fn get_metrics() -> Result<String> {
-    let (hostname, pools, cpu, memory, network, temperatures, disks, disk_usage): (
+    let (hostname, cpu, memory, network, temperatures, disks, disk_usage) = try_join! {
-        String,
-        Vec<DiskUsage>,
-        f64,
-        Memory,
-        _,
-        HashMap<TemperatureLabel, f32>,
-        _,
-        _,
-    ) = try_join! {
         hostname(),
-        pools(),
         cpu_time(),
         memory(),
         network_stats(),
@@ -29,6 +19,7 @@ pub async fn get_metrics() -> Result<String> {
         disk_stats(),
         disk_usage(),
     }?;
+    let pools = pools();
     pin_mut!(network);
     pin_mut!(disks);
     pin_mut!(disk_usage);

src/zfs.rs

@@ -1,31 +1,56 @@
 use crate::heim::DiskUsage;
 use color_eyre::Result;
 use std::process::Command;
-use tokio::task::spawn_blocking;
 
-pub async fn pools() -> Result<Vec<DiskUsage>> {
+pub fn pools() -> impl Iterator<Item = DiskUsage> {
-    spawn_blocking(move || {
+    OutputParser {
+        str: zpool_command().unwrap_or_default(),
+        pos: 0,
+    }
+}
+
+fn zpool_command() -> Result<String> {
     let mut z = Command::new("zpool");
     z.args(&["list", "-p", "-H", "-o", "name,size,free"]);
-        let out = match z.output() {
+    let out = z.output()?;
-            Ok(out) => out,
-            Err(_) => return Ok(Vec::new()),
-        };
     if out.status.success() {
-            let output = String::from_utf8(out.stdout)?;
+        Ok(String::from_utf8(out.stdout)?)
-            Ok(output
+    } else {
-                .lines()
+        Ok(String::new())
-                .flat_map(|line| {
+    }
+}
+
+fn parse_line(line: &str) -> Option<DiskUsage> {
     let mut parts = line.split_ascii_whitespace();
     let name = parts.next()?.to_string();
     let size = parts.next()?.parse().ok()?;
     let free = parts.next()?.parse().ok()?;
     Some(DiskUsage { name, size, free })
-                })
-                .collect())
-        } else {
-            Ok(Vec::new())
 }
-    })
+
-    .await?
+struct OutputParser {
+    str: String,
+    pos: usize,
+}
+
+impl Iterator for OutputParser {
+    type Item = DiskUsage;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        let str = self.str.as_str();
+        let line = match str[self.pos..].find('\n') {
+            Some(next_pos) => {
+                let old_pos = self.pos;
+                self.pos += next_pos;
+                Some(&str[old_pos..self.pos])
+            }
+            None if self.pos < str.len() => {
+                let old_pos = self.pos;
+                self.pos = str.len();
+                Some(&str[old_pos..])
+            }
+            None => None,
+        };
+        line.and_then(parse_line)
+    }
 }