turns out you never want to keep deltas in memory

Byron · Aug 4, 2020 · 657aa2c · 657aa2c
1 parent 1e2ec7e
commit 657aa2c
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Showing 5 changed files with 6 additions and 18 deletions.
diff --git a/git-odb/src/pack/index/write/consume.rs b/git-odb/src/pack/index/write/consume.rs
@@ -27,7 +27,7 @@ where
                 let mut bytes_buf = bytes_buf.borrow_mut();
                 bytes_buf.resize(entry_size, 0);
                 match mode {
-                    Mode::ResolveDeltas | Mode::ResolveBases | Mode::ResolveBasesAndDeltas => {
+                    Mode::ResolveDeltas | Mode::ResolveBasesAndDeltas => {
                         resolve(pack_offset..pack_offset + entry_size as u64, &mut bytes_buf)
                             .ok_or_else(|| Error::ConsumeResolveFailed(pack_offset))?;
                         let entry = pack::data::Entry::from_bytes(&bytes_buf, pack_offset);

diff --git a/git-odb/src/pack/index/write/types.rs b/git-odb/src/pack/index/write/types.rs
@@ -67,8 +67,6 @@ pub type EntrySlice = std::ops::Range<u64>;
 pub enum Mode {
     /// Base + deltas in memory, decompressed
     InMemory,
-    /// Deltas in memory, decompressed
-    ResolveBases,
     /// Bases in memory, decompressed
     ResolveDeltas,
     ResolveBasesAndDeltas,
@@ -78,19 +76,19 @@ impl Mode {
     pub(crate) fn base_cache(&self, decompressed: Vec<u8>) -> Cache {
         match self {
             Mode::InMemory | Mode::ResolveDeltas => Cache::Decompressed(decompressed),
-            Mode::ResolveBases | Mode::ResolveBasesAndDeltas => Cache::Unset,
+            Mode::ResolveBasesAndDeltas => Cache::Unset,
         }
     }
     pub(crate) fn delta_cache(&self, decompressed: Vec<u8>) -> Cache {
         match self {
-            Mode::ResolveBases | Mode::InMemory => Cache::Decompressed(decompressed),
+            Mode::InMemory => Cache::Decompressed(decompressed),
             Mode::ResolveDeltas | Mode::ResolveBasesAndDeltas => Cache::Unset,
         }
     }
     pub(crate) fn is_in_memory(&self) -> bool {
         match self {
             Mode::InMemory => true,
-            Mode::ResolveBases | Mode::ResolveDeltas | Mode::ResolveBasesAndDeltas => false,
+            Mode::ResolveDeltas | Mode::ResolveBasesAndDeltas => false,
         }
     }
 }

diff --git a/git-odb/tests/pack/tree.rs b/git-odb/tests/pack/tree.rs
@@ -1,9 +1,5 @@
 #[test]
 fn using_option_as_data_does_not_increase_size_in_memory() {
-    enum Cache {
-        _Unset,
-        _Decompressed(Vec<u8>),
-    }
     enum ObjectKind {
         _Base(git_object::Kind),
         _OfsDelta,
@@ -14,7 +10,6 @@ fn using_option_as_data_does_not_increase_size_in_memory() {
         pub _entry_len: usize,
         pub _kind: ObjectKind,
         pub _crc32: u32,
-        pub _cache: Cache,
     }
 
     struct TreeItem<D> {
@@ -34,7 +29,7 @@ fn using_option_as_data_does_not_increase_size_in_memory() {
     );
     assert_eq!(
         std::mem::size_of::<[TreeItemOption<Entry>; 7_500_000]>(),
-        780000000,
+        600_000_000,
         "it should be as small as possible"
     );
 }
diff --git a/gitoxide-core/src/pack/index.rs b/gitoxide-core/src/pack/index.rs
@@ -44,7 +44,6 @@ impl From<IterationMode> for pack::data::iter::Mode {
 #[derive(PartialEq, Debug)]
 pub enum MemoryMode {
     InMemory,
-    ResolveBases,
     ResolveDeltas,
     ResolveBasesAndDeltas,
 }
@@ -63,7 +62,6 @@ impl FromStr for MemoryMode {
         let slc = s.to_ascii_lowercase();
         Ok(match slc.as_str() {
             "in-memory" => InMemory,
-            "resolve-bases" => ResolveBases,
             "resolve-deltas" => ResolveDeltas,
             "resolve-bases-and-deltas" => ResolveBasesAndDeltas,
             _ => return Err("invalid value".into()),
@@ -76,7 +74,6 @@ impl From<MemoryMode> for pack::index::write::Mode {
         use pack::index::write::Mode::*;
         match v {
             MemoryMode::InMemory => InMemory,
-            MemoryMode::ResolveBases => ResolveBases,
             MemoryMode::ResolveDeltas => ResolveDeltas,
             MemoryMode::ResolveBasesAndDeltas => ResolveBasesAndDeltas,
         }

diff --git a/src/plumbing/lean.rs b/src/plumbing/lean.rs
@@ -55,10 +55,8 @@ mod options {
         /// Valid values are
         /// - in-memory
         ///   *  keep all objects in memory, decompressed, avoiding decompression entirely.
-        /// - resolve-bases
-        ///   * keep compressed deltas in memory, store the pack on disk and resolve bases from there
         /// - resolve-deltas
-        ///   * as above, but keep compressed bases
+        ///   * keep compressed bases in memory, store the pack on disk and resolve deltas from there
         /// - resolve-bases-and-deltas
         ///   * as above, but resolve all objects, store none in memory
         ///   * this option duplicates most work, but uses the least memory