Logging timestamp size record in WAL and use it during recovery (#11471)

Summary:
Start logging the timestamp size record in WAL and use the record during recovery.  Currently, user comparator cannot be different from what was used to create a column family, so the timestamp size record is just used to confirm it's consistent with the timestamp size the running user comparator indicates.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11471

Test Plan:
```
make all check
./db_secondary_test
./db_wal_test --gtest_filter="*WithTimestamp*"
./repair_test --gtest_filter="*WithTimestamp*"
```

Reviewed By: ltamasi

Differential Revision: D46236769

Pulled By: jowlyzhang

fbshipit-source-id: f6c60b5c8defdb05021c63df302ccc0be1275ad0

1 files changed, 19 insertions, 0 deletions

diff --git a/db/column_family.h b/db/column_family.h
index 9ec093010..5fe593a84 100644
--- a/db/column_family.h
+++ b/db/column_family.h
@@ -705,6 +705,16 @@ class ColumnFamilySet {
                                        Version* dummy_version,
                                        const ColumnFamilyOptions& options);
 
+  const std::unordered_map<uint32_t, size_t>&
+  GetRunningColumnFamiliesTimestampSize() const {
+    return running_ts_sz_;
+  }
+
+  const std::unordered_map<uint32_t, size_t>&
+  GetColumnFamiliesTimestampSizeForRecord() const {
+    return ts_sz_for_record_;
+  }
+
   iterator begin() { return iterator(dummy_cfd_->next_); }
   iterator end() { return iterator(dummy_cfd_); }
 
@@ -730,6 +740,15 @@ class ColumnFamilySet {
   UnorderedMap<std::string, uint32_t> column_families_;
   UnorderedMap<uint32_t, ColumnFamilyData*> column_family_data_;
 
+  // Mutating / reading `running_ts_sz_` and `ts_sz_for_record_` follow
+  // the same requirements as `column_families_` and `column_family_data_`.
+  // Mapping from column family id to user-defined timestamp size for all
+  // running column families.
+  std::unordered_map<uint32_t, size_t> running_ts_sz_;
+  // Mapping from column family id to user-defined timestamp size for
+  // column families with non-zero user-defined timestamp size.
+  std::unordered_map<uint32_t, size_t> ts_sz_for_record_;
+
   uint32_t max_column_family_;
   const FileOptions file_options_;