[sled-diagnostics] log collection should happen on u.2s (#8438)

Author: papertigers

illumos-utils/src/zfs.rs

@@ -1308,7 +1308,7 @@ impl Zfs {
             .collect::<Result<Vec<&str>, GetValueError>>()?
             .join(",");
 
-        cmd.args(&[ZFS, "get", "-Ho", "value"]);
+        cmd.args(&[ZFS, "get", "-Hpo", "value"]);
         if let Some(source) = source {
             cmd.args(&["-s", &source.to_string()]);
         }

sled-agent/src/sled_agent.rs

@@ -703,7 +703,7 @@ impl SledAgent {
     pub(crate) fn as_support_bundle_logs(&self) -> SupportBundleLogs<'_> {
         SupportBundleLogs::new(
             &self.log,
-            self.inner.config_reconciler.internal_disks_rx(),
+            self.inner.config_reconciler.available_datasets_rx(),
         )
     }
 

sled-agent/src/support_bundle/logs.rs

@@ -6,8 +6,10 @@
 
 use camino_tempfile::tempfile_in;
 use dropshot::HttpError;
+use futures::StreamExt;
+use futures::stream::FuturesUnordered;
 use range_requests::make_get_response;
-use sled_agent_config_reconciler::InternalDisksReceiver;
+use sled_agent_config_reconciler::AvailableDatasetsReceiver;
 use slog::Logger;
 use slog_error_chain::InlineErrorChain;
 use tokio::io::AsyncSeekExt;
@@ -43,15 +45,15 @@ impl From<Error> for HttpError {
 
 pub struct SupportBundleLogs<'a> {
     log: &'a Logger,
-    internal_disks_rx: &'a InternalDisksReceiver,
+    available_datasets_rx: AvailableDatasetsReceiver,
 }
 
 impl<'a> SupportBundleLogs<'a> {
     pub fn new(
         log: &'a Logger,
-        internal_disks_rx: &'a InternalDisksReceiver,
+        available_datasets_rx: AvailableDatasetsReceiver,
     ) -> Self {
-        Self { log, internal_disks_rx }
+        Self { log, available_datasets_rx }
     }
 
     /// Get a list of zones on a sled containing logs that we want to include in
@@ -78,12 +80,53 @@ impl<'a> SupportBundleLogs<'a> {
     where
         Z: Into<String>,
     {
-        // We are using an M.2 device for temporary storage to assemble a zip
-        // file made up of all of the discovered zone's logs.
-        let current_internal_disks = self.internal_disks_rx.current();
-        let mut m2_debug_datasets = current_internal_disks.all_debug_datasets();
-        let tempdir = m2_debug_datasets.next().ok_or(Error::MissingStorage)?;
-        let mut tempfile = tempfile_in(tempdir)?;
+        // Attempt to find a U.2 device with the most available free space
+        // for temporary storage to assemble a zip file made up of all of the
+        // discovered zone's logs.
+        let mounted_debug_datasets =
+            self.available_datasets_rx.all_mounted_debug_datasets();
+        let storage_paths_to_size: Vec<_> = mounted_debug_datasets
+            .into_iter()
+            .map(|dataset_path| {
+                let path = dataset_path.path;
+                async move {
+                    match illumos_utils::zfs::Zfs::get_value(
+                        path.as_str(),
+                        "available",
+                    )
+                    .await
+                    {
+                        Ok(size_str) => match size_str.parse::<usize>() {
+                            Ok(size) => Some((path, size)),
+                            Err(e) => {
+                                warn!(
+                                    &self.log,
+                                    "failed to parse available size for the \
+                                    dataset at path {path}: {e}"
+                                );
+                                None
+                            }
+                        },
+                        Err(e) => {
+                            warn!(
+                                &self.log,
+                                "failed to get available size for the  dataset \
+                                at path {path}: {e}"
+                            );
+                            None
+                        }
+                    }
+                }
+            })
+            .collect::<FuturesUnordered<_>>()
+            .collect()
+            .await;
+        let (largest_avail_space, _) = storage_paths_to_size
+            .into_iter()
+            .flatten()
+            .max_by_key(|(_, size)| *size)
+            .ok_or(Error::MissingStorage)?;
+        let mut tempfile = tempfile_in(largest_avail_space)?;
 
         let log = self.log.clone();
         let zone = zone.into();

sled-storage/src/resources.rs

@@ -209,15 +209,6 @@ impl AllDisks {
             .collect()
     }
 
-    /// Return the directories that can be used for temporary sled-diagnostics
-    /// file storage.
-    pub fn all_sled_diagnostics_directories(&self) -> Vec<Utf8PathBuf> {
-        // These directories are currently used for tempfile storage when
-        // zipping up zone logs before shuffling them off to a nexus collecting
-        // a support bundle.
-        self.all_m2_mountpoints(M2_DEBUG_DATASET).into_iter().collect()
-    }
-
     /// Returns an iterator over all managed disks.
     pub fn iter_managed(&self) -> impl Iterator<Item = (&DiskIdentity, &Disk)> {
         self.inner.values.iter().filter_map(|(identity, disk)| match disk {