Typo about subxip in comments

Hi, hackers

Recently, when I read the XidInMVCCSnapshot(), and find there are some
typos in the comments.

diff --git a/src/backend/storage/ipc/procarray.c b/src/backend/storage/ipc/procarray.c
index 207c4b27fd..9e8b6756fe 100644
--- a/src/backend/storage/ipc/procarray.c
+++ b/src/backend/storage/ipc/procarray.c
@@ -2409,7 +2409,7 @@ GetSnapshotData(Snapshot snapshot)
 		 * We could try to store xids into xip[] first and then into subxip[]
 		 * if there are too many xids. That only works if the snapshot doesn't
 		 * overflow because we do not search subxip[] in that case. A simpler
-		 * way is to just store all xids in the subxact array because this is
+		 * way is to just store all xids in the subxip array because this is
 		 * by far the bigger array. We just leave the xip array empty.
 		 *
 		 * Either way we need to change the way XidInMVCCSnapshot() works
diff --git a/src/backend/utils/time/snapmgr.c b/src/backend/utils/time/snapmgr.c
index f1f2ddac17..2524b1c585 100644
--- a/src/backend/utils/time/snapmgr.c
+++ b/src/backend/utils/time/snapmgr.c
@@ -2345,7 +2345,7 @@ XidInMVCCSnapshot(TransactionId xid, Snapshot snapshot)
 	else
 	{
 		/*
-		 * In recovery we store all xids in the subxact array because it is by
+		 * In recovery we store all xids in the subxip array because it is by
 		 * far the bigger array, and we mostly don't know which xids are
 		 * top-level and which are subxacts. The xip array is empty.
 		 *

-- 
Regrads,
Japin Li.
ChengDu WenWu Information Technology Co.,Ltd.