diff --git a/src/include/access/xlog_internal.h b/src/include/access/xlog_internal.h
index e3f616a..08d6494 100644
--- a/src/include/access/xlog_internal.h
+++ b/src/include/access/xlog_internal.h
@@ -93,10 +93,12 @@ typedef XLogLongPageHeaderData *XLogLongPageHeader;
 extern uint32 XLogSegSize;
 #define XLOG_SEG_SIZE XLogSegSize
 
-/* XLogSegSize can range from 1MB to 1GB */
-#define XLogSegMinSize 1024 * 1024
+/* XLogSegSize can range from 16MB to 1GB */
+#define XLogSegMinSize 1024 * 1024 * 16
 #define XLogSegMaxSize 1024 * 1024 * 1024
 
+#define XLogSegMinSizeBits 24
+
 /* Default number of min and max wal segments */
 #define DEFAULT_MIN_WAL_SEGS 5
 #define DEFAULT_MAX_WAL_SEGS 64
@@ -158,10 +160,14 @@ extern uint32 XLogSegSize;
 /* Length of XLog file name */
 #define XLOG_FNAME_LEN	   24
 
+#define XLogSegNoLower(logSegNo) \
+	(((logSegNo) % XLogSegmentsPerXLogId) *	\
+		(XLogSegSize >> XLogSegMinSizeBits))
+
 #define XLogFileName(fname, tli, logSegNo)	\
 	snprintf(fname, MAXFNAMELEN, "%08X%08X%08X", tli,		\
 			 (uint32) ((logSegNo) / XLogSegmentsPerXLogId), \
-			 (uint32) ((logSegNo) % XLogSegmentsPerXLogId))
+			 (uint32) XLogSegNoLower(logSegNo))
 
 #define XLogFileNameById(fname, tli, log, seg)	\
 	snprintf(fname, MAXFNAMELEN, "%08X%08X%08X", tli, log, seg)
@@ -181,17 +187,18 @@ extern uint32 XLogSegSize;
 	 strcmp((fname) + XLOG_FNAME_LEN, ".partial") == 0)
 
 #define XLogFromFileName(fname, tli, logSegNo)	\
-	do {												\
-		uint32 log;										\
-		uint32 seg;										\
-		sscanf(fname, "%08X%08X%08X", tli, &log, &seg); \
-		*logSegNo = (uint64) log * XLogSegmentsPerXLogId + seg; \
+	do {													\
+		uint32 log;											\
+		uint32 seg;											\
+		sscanf(fname, "%08X%08X%08X", tli, &log, &seg); 	\
+		*logSegNo = (uint64) log * XLogSegmentsPerXLogId + 	\
+			(seg / (XLogSegSize >> XLogSegMinSizeBits)); \
 	} while (0)
 
 #define XLogFilePath(path, tli, logSegNo)	\
 	snprintf(path, MAXPGPATH, XLOGDIR "/%08X%08X%08X", tli,				\
 			 (uint32) ((logSegNo) / XLogSegmentsPerXLogId),				\
-			 (uint32) ((logSegNo) % XLogSegmentsPerXLogId))
+			 (uint32) XLogSegNoLower(logSegNo))
 
 #define TLHistoryFileName(fname, tli)	\
 	snprintf(fname, MAXFNAMELEN, "%08X.history", tli)
@@ -210,7 +217,7 @@ extern uint32 XLogSegSize;
 #define BackupHistoryFileName(fname, tli, logSegNo, offset) \
 	snprintf(fname, MAXFNAMELEN, "%08X%08X%08X.%08X.backup", tli, \
 			 (uint32) ((logSegNo) / XLogSegmentsPerXLogId),		  \
-			 (uint32) ((logSegNo) % XLogSegmentsPerXLogId), offset)
+			 (uint32) XLogSegNoLower(logSegNo), offset)
 
 #define IsBackupHistoryFileName(fname) \
 	(strlen(fname) > XLOG_FNAME_LEN && \
@@ -220,7 +227,7 @@ extern uint32 XLogSegSize;
 #define BackupHistoryFilePath(path, tli, logSegNo, offset)	\
 	snprintf(path, MAXPGPATH, XLOGDIR "/%08X%08X%08X.%08X.backup", tli, \
 			 (uint32) ((logSegNo) / XLogSegmentsPerXLogId), \
-			 (uint32) ((logSegNo) % XLogSegmentsPerXLogId), offset)
+			 (uint32) XLogSegNoLower(logSegNo), offset)
 
 /*
  * Information logged when we detect a change in one of the parameters