From cf459b1982bc043f595fa7ab8e2981c5bdca038c Mon Sep 17 00:00:00 2001
From: Dietmar Maurer <dietmar@proxmox.com>
Date: Mon, 6 Apr 2020 09:50:40 +0200
Subject: [PATCH] gc: log pending removals

---
 src/api2/types.rs         |  6 ++++++
 src/backup/chunk_store.rs | 24 +++++++++++++-----------
 src/backup/datastore.rs   |  8 +++++++-
 3 files changed, 26 insertions(+), 12 deletions(-)

diff --git a/src/api2/types.rs b/src/api2/types.rs
index d06a5cc9..806ba4ba 100644
--- a/src/api2/types.rs
+++ b/src/api2/types.rs
@@ -313,6 +313,10 @@ pub struct GarbageCollectionStatus {
     pub removed_bytes: u64,
     /// Number of removed chunks.
     pub removed_chunks: usize,
+    /// Sum of pending bytes (pending removal - kept for safety).
+    pub pending_bytes: u64,
+    /// Number of pending chunks (pending removal - kept for safety).
+    pub pending_chunks: usize,
 }
 
 impl Default for GarbageCollectionStatus {
@@ -325,6 +329,8 @@ impl Default for GarbageCollectionStatus {
             disk_chunks: 0,
             removed_bytes: 0,
             removed_chunks: 0,
+            pending_bytes: 0,
+            pending_chunks: 0,
         }
     }
 }
diff --git a/src/backup/chunk_store.rs b/src/backup/chunk_store.rs
index fa9c2710..906b0f7d 100644
--- a/src/backup/chunk_store.rs
+++ b/src/backup/chunk_store.rs
@@ -289,7 +289,7 @@ impl ChunkStore {
 
     pub fn sweep_unused_chunks(
         &self,
-        oldest_writer: Option<i64>,
+        oldest_writer: i64,
         status: &mut GarbageCollectionStatus,
         worker: Arc<WorkerTask>,
     ) -> Result<(), Error> {
@@ -299,10 +299,8 @@ impl ChunkStore {
 
         let mut min_atime = now - 3600*24; // at least 24h (see mount option relatime)
 
-        if let Some(stamp) = oldest_writer {
-            if stamp < min_atime {
-                min_atime = stamp;
-            }
+        if oldest_writer < min_atime {
+            min_atime = oldest_writer;
         }
 
         min_atime -= 300; // add 5 mins gap for safety
@@ -338,10 +336,9 @@ impl ChunkStore {
             let lock = self.mutex.lock();
 
             if let Ok(stat) = fstatat(dirfd, filename, nix::fcntl::AtFlags::AT_SYMLINK_NOFOLLOW) {
-                let age = now - stat.st_atime;
-                //println!("FOUND {}  {:?}", age/(3600*24), filename);
                 if stat.st_atime < min_atime {
-                    println!("UNLINK {}  {:?}", age/(3600*24), filename);
+                    //let age = now - stat.st_atime;
+                    //println!("UNLINK {}  {:?}", age/(3600*24), filename);
                     let res = unsafe { libc::unlinkat(dirfd, filename.as_ptr(), 0) };
                     if res != 0 {
                         let err = nix::Error::last();
@@ -354,9 +351,14 @@ impl ChunkStore {
                     }
                     status.removed_chunks += 1;
                     status.removed_bytes += stat.st_size as u64;
-               } else {
-                    status.disk_chunks += 1;
-                    status.disk_bytes += stat.st_size as u64;
+                } else {
+                    if stat.st_atime < oldest_writer {
+                        status.pending_chunks += 1;
+                        status.pending_bytes += stat.st_size as u64;
+                    } else {
+                        status.disk_chunks += 1;
+                        status.disk_bytes += stat.st_size as u64;
+                     }
                 }
             }
             drop(lock);
diff --git a/src/backup/datastore.rs b/src/backup/datastore.rs
index d4ee7dd4..3ee48fee 100644
--- a/src/backup/datastore.rs
+++ b/src/backup/datastore.rs
@@ -338,7 +338,9 @@ impl DataStore {
 
             let _exclusive_lock =  self.chunk_store.try_exclusive_lock()?;
 
-            let oldest_writer = self.chunk_store.oldest_writer();
+            let now = unsafe { libc::time(std::ptr::null_mut()) };
+
+            let oldest_writer = self.chunk_store.oldest_writer().unwrap_or(now);
 
             let mut gc_status = GarbageCollectionStatus::default();
             gc_status.upid = Some(worker.to_string());
@@ -352,6 +354,10 @@ impl DataStore {
 
             worker.log(&format!("Removed bytes: {}", gc_status.removed_bytes));
             worker.log(&format!("Removed chunks: {}", gc_status.removed_chunks));
+            if gc_status.pending_bytes > 0 {
+                worker.log(&format!("Pending removals: {} bytes ({} chunks)", gc_status.pending_bytes, gc_status.pending_chunks));
+            }
+
             worker.log(&format!("Original data bytes: {}", gc_status.index_data_bytes));
 
             if gc_status.index_data_bytes > 0 {