fix typo (#11595)

Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/11595

Reviewed By: ajkr

Differential Revision: D47600701

Pulled By: jowlyzhang

fbshipit-source-id: 22375b51c726b176e4bc502b49cf3343f45f8a0a

table/block_based/block_based_table_factory.cc

@@ -83,7 +83,7 @@ size_t TailPrefetchStats::GetSuggestedPrefetchSize() {
   //
   // and we use every of the value as a candidate, and estimate how much we
   // wasted, compared to read. For example, when we use the 3rd record
-  // as candiate. This area is what we read:
+  // as candidate. This area is what we read:
   //                                     +---+
   //                             +---+   |   |
   //                             |   |   |   |
@@ -123,7 +123,7 @@ size_t TailPrefetchStats::GetSuggestedPrefetchSize() {
   //  +---+    +---+    +---+    +---+   +---+
   //
   // Which can be calculated iteratively.
-  // The difference between wasted using 4st and 3rd record, will
+  // The difference between wasted using 4th and 3rd record, will
   // be following area:
   //                                     +---+
   //  +--+  +-+   ++  +-+  +-+   +---+   |   |
@@ -143,8 +143,8 @@ size_t TailPrefetchStats::GetSuggestedPrefetchSize() {
   //  |   |    |   |    |   |    |   |   |   |
   //  +---+    +---+    +---+    +---+   +---+
   //
-  // which will be the size difference between 4st and 3rd record,
+  // which will be the size difference between 4th and 3rd record,
-  // times 3, which is number of records before the 4st.
+  // times 3, which is number of records before the 4th.
   // Here we assume that all data within the prefetch range will be useful. In
   // reality, it may not be the case when a partial block is inside the range,
   // or there are data in the middle that is not read. We ignore those cases