diff --git a/src/archive.c b/src/archive.c
index 2ae86bd6a..734602cac 100644
--- a/src/archive.c
+++ b/src/archive.c
@@ -1375,11 +1375,11 @@ get_wal_file(const char *filename, const char *from_fullpath,
 #ifdef HAVE_LIBZ
 		/* If requested file is regular WAL segment, then try to open it with '.gz' suffix... */
 		if (IsXLogFileName(filename))
-			rc = fio_send_file_gz(from_fullpath_gz, to_fullpath, out, &errmsg);
+			rc = fio_send_file_gz(from_fullpath_gz, out, &errmsg);
 		if (rc == FILE_MISSING)
 #endif
 			/* ... failing that, use uncompressed */
-			rc = fio_send_file(from_fullpath, to_fullpath, out, NULL, &errmsg);
+			rc = fio_send_file(from_fullpath, out, false, NULL, &errmsg);
 
 		/* When not in prefetch mode, try to use partial file */
 		if (rc == FILE_MISSING && !prefetch_mode && IsXLogFileName(filename))
@@ -1389,13 +1389,13 @@ get_wal_file(const char *filename, const char *from_fullpath,
 #ifdef HAVE_LIBZ
 			/* '.gz.partial' goes first ... */
 			snprintf(from_partial, sizeof(from_partial), "%s.gz.partial", from_fullpath);
-			rc = fio_send_file_gz(from_partial, to_fullpath, out, &errmsg);
+			rc = fio_send_file_gz(from_partial, out, &errmsg);
 			if (rc == FILE_MISSING)
 #endif
 			{
 				/* ... failing that, use '.partial' */
 				snprintf(from_partial, sizeof(from_partial), "%s.partial", from_fullpath);
-				rc = fio_send_file(from_partial, to_fullpath, out, NULL, &errmsg);
+				rc = fio_send_file(from_partial, out, false, NULL, &errmsg);
 			}
 
 			if (rc == SEND_OK)
diff --git a/src/catalog.c b/src/catalog.c
index 03099d1a2..9668427bb 100644
--- a/src/catalog.c
+++ b/src/catalog.c
@@ -1069,6 +1069,7 @@ get_backup_filelist(pgBackup *backup, bool strict)
 		char		linked[MAXPGPATH];
 		char		compress_alg_string[MAXPGPATH];
 		int64		write_size,
+					full_size,
 					mode,		/* bit length of mode_t depends on platforms */
 					is_datafile,
 					is_cfs,
@@ -1087,6 +1088,8 @@ get_backup_filelist(pgBackup *backup, bool strict)
 
         get_control_value_str(buf, "path", path, sizeof(path),true);
         get_control_value_int64(buf, "size", &write_size, true);
+		if (!get_control_value_int64(buf, "full_size", &full_size, false))
+			full_size = write_size;
         get_control_value_int64(buf, "mode", &mode, true);
         get_control_value_int64(buf, "is_datafile", &is_datafile, true);
         get_control_value_int64(buf, "is_cfs", &is_cfs, false);
@@ -1097,6 +1100,7 @@ get_backup_filelist(pgBackup *backup, bool strict)
 
 		file = pgFileInit(path);
 		file->write_size = (int64) write_size;
+		file->uncompressed_size = full_size;
 		file->mode = (mode_t) mode;
 		file->is_datafile = is_datafile ? true : false;
 		file->is_cfs = is_cfs ? true : false;
@@ -2561,6 +2565,11 @@ write_backup_filelist(pgBackup *backup, parray *files, const char *root,
 					file->external_dir_num,
 					file->dbOid);
 
+		if (file->uncompressed_size != 0 &&
+				file->uncompressed_size != file->write_size)
+			len += sprintf(line+len, ",\"full_size\":\"" INT64_FORMAT "\"",
+						   file->uncompressed_size);
+
 		if (file->is_datafile)
 			len += sprintf(line+len, ",\"segno\":\"%d\"", file->segno);
 
diff --git a/src/data.c b/src/data.c
index 753f247f7..5a2784eb2 100644
--- a/src/data.c
+++ b/src/data.c
@@ -799,6 +799,7 @@ backup_non_data_file(pgFile *file, pgFile *prev_file,
 	 * and its mtime is less than parent backup start time ... */
 	if ((pg_strcasecmp(file->name, RELMAPPER_FILENAME) != 0) &&
 		(prev_file && file->exists_in_prev &&
+		 file->size == prev_file->size &&
 		 file->mtime <= parent_backup_time))
 	{
 		/*
@@ -1387,10 +1388,12 @@ backup_non_data_file_internal(const char *from_fullpath,
 							const char *to_fullpath, pgFile *file,
 							bool missing_ok)
 {
-	FILE	*in = NULL;
 	FILE	*out = NULL;
-	ssize_t  read_len = 0;
-	char	*buf = NULL;
+	char	*errmsg = NULL;
+	int 	rc;
+	bool	cut_zero_tail;
+
+	cut_zero_tail = file->forkName == cfm;
 
 	INIT_FILE_CRC32(true, file->crc);
 
@@ -1412,107 +1415,43 @@ backup_non_data_file_internal(const char *from_fullpath,
 
 	/* backup remote file  */
 	if (fio_is_remote(FIO_DB_HOST))
-	{
-		char *errmsg = NULL;
-		int rc = fio_send_file(from_fullpath, to_fullpath, out, file, &errmsg);
+		rc = fio_send_file(from_fullpath, out, cut_zero_tail, file, &errmsg);
+	else
+		rc = fio_send_file_local(from_fullpath, out, cut_zero_tail, file, &errmsg);
 
-		/* handle errors */
-		if (rc == FILE_MISSING)
-		{
-			/* maybe deleted, it's not error in case of backup */
-			if (missing_ok)
-			{
-				elog(LOG, "File \"%s\" is not found", from_fullpath);
-				file->write_size = FILE_NOT_FOUND;
-				goto cleanup;
-			}
-			else
-				elog(ERROR, "File \"%s\" is not found", from_fullpath);
-		}
-		else if (rc == WRITE_FAILED)
-			elog(ERROR, "Cannot write to \"%s\": %s", to_fullpath, strerror(errno));
-		else if (rc != SEND_OK)
+	/* handle errors */
+	if (rc == FILE_MISSING)
+	{
+		/* maybe deleted, it's not error in case of backup */
+		if (missing_ok)
 		{
-			if (errmsg)
-				elog(ERROR, "%s", errmsg);
-			else
-				elog(ERROR, "Cannot access remote file \"%s\"", from_fullpath);
+			elog(LOG, "File \"%s\" is not found", from_fullpath);
+			file->write_size = FILE_NOT_FOUND;
+			goto cleanup;
 		}
-
-		pg_free(errmsg);
+		else
+			elog(ERROR, "File \"%s\" is not found", from_fullpath);
 	}
-	/* backup local file */
-	else
+	else if (rc == WRITE_FAILED)
+		elog(ERROR, "Cannot write to \"%s\": %s", to_fullpath, strerror(errno));
+	else if (rc != SEND_OK)
 	{
-		/* open source file for read */
-		in = fopen(from_fullpath, PG_BINARY_R);
-		if (in == NULL)
-		{
-			/* maybe deleted, it's not error in case of backup */
-			if (errno == ENOENT)
-			{
-				if (missing_ok)
-				{
-					elog(LOG, "File \"%s\" is not found", from_fullpath);
-					file->write_size = FILE_NOT_FOUND;
-					goto cleanup;
-				}
-				else
-					elog(ERROR, "File \"%s\" is not found", from_fullpath);
-			}
-
-			elog(ERROR, "Cannot open file \"%s\": %s", from_fullpath,
-				 strerror(errno));
-		}
-
-		/* disable stdio buffering for local input/output files to avoid triple buffering */
-		setvbuf(in, NULL, _IONBF, BUFSIZ);
-		setvbuf(out, NULL, _IONBF, BUFSIZ);
-
-		/* allocate 64kB buffer */
-		buf = pgut_malloc(CHUNK_SIZE);
-
-		/* copy content and calc CRC */
-		for (;;)
-		{
-			read_len = fread(buf, 1, CHUNK_SIZE, in);
-
-			if (ferror(in))
-				elog(ERROR, "Cannot read from file \"%s\": %s",
-					 from_fullpath, strerror(errno));
-
-			if (read_len > 0)
-			{
-				if (fwrite(buf, 1, read_len, out) != read_len)
-					elog(ERROR, "Cannot write to file \"%s\": %s", to_fullpath,
-						 strerror(errno));
-
-				/* update CRC */
-				COMP_FILE_CRC32(true, file->crc, buf, read_len);
-				file->read_size += read_len;
-			}
-
-			if (feof(in))
-				break;
-		}
+		if (errmsg)
+			elog(ERROR, "%s", errmsg);
+		else
+			elog(ERROR, "Cannot access remote file \"%s\"", from_fullpath);
 	}
 
-	file->write_size = (int64) file->read_size;
+	pg_free(errmsg); /* ????? */
 
-	if (file->write_size > 0)
-		file->uncompressed_size = file->write_size;
+	file->uncompressed_size = file->read_size;
 
 cleanup:
 	/* finish CRC calculation and store into pgFile */
 	FIN_FILE_CRC32(true, file->crc);
 
-	if (in && fclose(in))
-		elog(ERROR, "Cannot close the file \"%s\": %s", from_fullpath, strerror(errno));
-
 	if (out && fclose(out))
 		elog(ERROR, "Cannot close the file \"%s\": %s", to_fullpath, strerror(errno));
-
-	pg_free(buf);
 }
 
 /*
diff --git a/src/dir.c b/src/dir.c
index 00e918d0f..c7d3b535c 100644
--- a/src/dir.c
+++ b/src/dir.c
@@ -324,6 +324,67 @@ pgFileGetCRC(const char *file_path, bool use_crc32c, bool missing_ok)
 	return crc;
 }
 
+static const char zerobuf[4096] = {0};
+
+/*
+ * Read the local file to compute CRC for it extened to real_size.
+ */
+pg_crc32
+pgFileGetCRCForTruncated(const char *file_path, bool use_crc32c, int64_t real_size)
+{
+	FILE	   *fp;
+	pg_crc32	crc = 0;
+	char	   *buf;
+	size_t		len = 0;
+	int64_t 	read_size = 0;
+
+	INIT_FILE_CRC32(use_crc32c, crc);
+
+	/* open file in binary read mode */
+	fp = fopen(file_path, PG_BINARY_R);
+	if (fp == NULL)
+	{
+		elog(ERROR, "Cannot open file \"%s\": %s",
+			 file_path, strerror(errno));
+	}
+
+	/* disable stdio buffering */
+	setvbuf(fp, NULL, _IONBF, BUFSIZ);
+	buf = pgut_malloc(STDIO_BUFSIZE);
+
+	/* calc CRC of file */
+	for (;;)
+	{
+		if (interrupted)
+			elog(ERROR, "interrupted during CRC calculation");
+
+		len = fread(buf, 1, STDIO_BUFSIZE, fp);
+
+		if (ferror(fp))
+			elog(ERROR, "Cannot read \"%s\": %s", file_path, strerror(errno));
+
+		/* update CRC */
+		COMP_FILE_CRC32(use_crc32c, crc, buf, len);
+
+		read_size += len;
+
+		if (feof(fp))
+			break;
+	}
+
+	while (read_size < real_size)
+	{
+		len = Min(real_size - read_size, sizeof(zerobuf));
+		COMP_FILE_CRC32(use_crc32c, crc, zerobuf, len);
+		read_size += len;
+	}
+
+	FIN_FILE_CRC32(use_crc32c, crc);
+	fclose(fp);
+	pg_free(buf);
+
+	return crc;
+}
 /*
  * Read the local file to compute its CRC.
  * We cannot make decision about file decompression because
@@ -1812,7 +1873,7 @@ write_database_map(pgBackup *backup, parray *database_map, parray *backup_files_
 								 FIO_BACKUP_HOST);
 	file->crc = pgFileGetCRC(database_map_path, true, false);
 	file->write_size = file->size;
-	file->uncompressed_size = file->read_size;
+	file->uncompressed_size = file->size;
 
 	parray_append(backup_files_list, file);
 }
diff --git a/src/merge.c b/src/merge.c
index 1ce49f9a2..79498f48c 100644
--- a/src/merge.c
+++ b/src/merge.c
@@ -1078,7 +1078,7 @@ merge_files(void *arg)
 					tmp_file->hdr_crc = file->hdr_crc;
 				}
 				else
-					tmp_file->uncompressed_size = tmp_file->write_size;
+					tmp_file->uncompressed_size = tmp_file->uncompressed_size;
 
 				/* Copy header metadata from old map into a new one */
 				tmp_file->n_headers = file->n_headers;
diff --git a/src/pg_probackup.h b/src/pg_probackup.h
index bc9f9b8a8..c2382cd3e 100644
--- a/src/pg_probackup.h
+++ b/src/pg_probackup.h
@@ -345,11 +345,11 @@ typedef enum ShowFormat
 #define BYTES_INVALID		(-1) /* file didn`t changed since previous backup, DELTA backup do not rely on it */
 #define FILE_NOT_FOUND		(-2) /* file disappeared during backup */
 #define BLOCKNUM_INVALID	(-1)
-#define PROGRAM_VERSION	"2.5.8"
+#define PROGRAM_VERSION	"2.5.9"
 
 /* update when remote agent API or behaviour changes */
-#define AGENT_PROTOCOL_VERSION 20501
-#define AGENT_PROTOCOL_VERSION_STR "2.5.1"
+#define AGENT_PROTOCOL_VERSION 20509
+#define AGENT_PROTOCOL_VERSION_STR "2.5.9"
 
 /* update only when changing storage format */
 #define STORAGE_FORMAT_VERSION "2.4.4"
@@ -1077,6 +1077,7 @@ extern void fio_pgFileDelete(pgFile *file, const char *full_path);
 extern void pgFileFree(void *file);
 
 extern pg_crc32 pgFileGetCRC(const char *file_path, bool use_crc32c, bool missing_ok);
+extern pg_crc32 pgFileGetCRCForTruncated(const char *file_path, bool use_crc32c, int64_t real_size);
 extern pg_crc32 pgFileGetCRCgz(const char *file_path, bool use_crc32c, bool missing_ok);
 
 extern int pgFileMapComparePath(const void *f1, const void *f2);
@@ -1240,9 +1241,11 @@ extern int fio_copy_pages(const char *to_fullpath, const char *from_fullpath, pg
 	                      XLogRecPtr horizonLsn, int calg, int clevel, uint32 checksum_version,
 	                      bool use_pagemap, BlockNumber *err_blknum, char **errormsg);
 /* return codes for fio_send_pages */
-extern int fio_send_file_gz(const char *from_fullpath, const char *to_fullpath, FILE* out, char **errormsg);
-extern int fio_send_file(const char *from_fullpath, const char *to_fullpath, FILE* out,
+extern int fio_send_file_gz(const char *from_fullpath, FILE* out, char **errormsg);
+extern int fio_send_file(const char *from_fullpath, FILE* out, bool cut_zero_tail,
 														pgFile *file, char **errormsg);
+extern int fio_send_file_local(const char *from_fullpath, FILE* out, bool cut_zero_tail,
+						 pgFile *file, char **errormsg);
 
 extern void fio_list_dir(parray *files, const char *root, bool exclude, bool follow_symlink,
 						 bool add_root, bool backup_logs, bool skip_hidden, int external_dir_num);
diff --git a/src/utils/file.c b/src/utils/file.c
index 727b48c60..7d389c53d 100644
--- a/src/utils/file.c
+++ b/src/utils/file.c
@@ -18,6 +18,10 @@ static __thread int fio_stdin = 0;
 static __thread int fio_stderr = 0;
 static char *async_errormsg = NULL;
 
+#define PAGE_ZEROSEARCH_COARSE_GRANULARITY 4096
+#define PAGE_ZEROSEARCH_FINE_GRANULARITY 64
+static const char zerobuf[PAGE_ZEROSEARCH_COARSE_GRANULARITY] = {0};
+
 fio_location MyLocation;
 
 typedef struct
@@ -2455,7 +2459,7 @@ fio_send_pages_impl(int out, char* buf)
  *   REMOTE_ERROR (-6)
  */
 int
-fio_send_file_gz(const char *from_fullpath, const char *to_fullpath, FILE* out, char **errormsg)
+fio_send_file_gz(const char *from_fullpath, FILE* out, char **errormsg)
 {
 	fio_header hdr;
 	int exit_code = SEND_OK;
@@ -2604,6 +2608,105 @@ fio_send_file_gz(const char *from_fullpath, const char *to_fullpath, FILE* out,
 	return exit_code;
 }
 
+typedef struct send_file_state {
+	bool		calc_crc;
+	uint32_t	crc;
+	int64_t		read_size;
+	int64_t		write_size;
+} send_file_state;
+
+/* find page border of all-zero tail */
+static size_t
+find_zero_tail(char *buf, size_t len)
+{
+	size_t i, l;
+	size_t granul = sizeof(zerobuf);
+
+	if (len == 0)
+		return 0;
+
+	/* fast check for last bytes */
+	l = Min(len, PAGE_ZEROSEARCH_FINE_GRANULARITY);
+	i = len - l;
+	if (memcmp(buf + i, zerobuf, l) != 0)
+		return len;
+
+	/* coarse search for zero tail */
+	i = (len-1) & ~(granul-1);
+	l = len - i;
+	for (;;)
+	{
+		if (memcmp(buf+i, zerobuf, l) != 0)
+		{
+			i += l;
+			break;
+		}
+		if (i == 0)
+			break;
+		i -= granul;
+		l = granul;
+	}
+
+	len = i;
+	/* search zero tail with finer granularity */
+	for (granul = sizeof(zerobuf)/2;
+		 len > 0 && granul >= PAGE_ZEROSEARCH_FINE_GRANULARITY;
+		 granul /= 2)
+	{
+		if (granul > l)
+			continue;
+		i = (len-1) & ~(granul-1);
+		l = len - i;
+		if (memcmp(buf+i, zerobuf, l) == 0)
+			len = i;
+	}
+
+	return len;
+}
+
+static void
+fio_send_file_crc(send_file_state* st, char *buf, size_t len)
+{
+	int64_t 	write_size;
+
+	if (!st->calc_crc)
+		return;
+
+	write_size = st->write_size;
+	while (st->read_size > write_size)
+	{
+		size_t	crc_len = Min(st->read_size - write_size, sizeof(zerobuf));
+		COMP_FILE_CRC32(true, st->crc, zerobuf, crc_len);
+		write_size += crc_len;
+	}
+
+	if (len > 0)
+		COMP_FILE_CRC32(true, st->crc, buf, len);
+}
+
+static bool
+fio_send_file_write(FILE* out, send_file_state* st, char *buf, size_t len)
+{
+	if (len == 0)
+		return true;
+
+	if (st->read_size > st->write_size &&
+		fseeko(out, st->read_size, SEEK_SET) != 0)
+	{
+		return false;
+	}
+
+	if (fwrite(buf, 1, len, out) != len)
+	{
+		return false;
+	}
+
+	st->read_size += len;
+	st->write_size = st->read_size;
+
+	return true;
+}
+
 /* Receive chunks of data and write them to destination file.
  * Return codes:
  *   SEND_OK       (0)
@@ -2616,13 +2719,22 @@ fio_send_file_gz(const char *from_fullpath, const char *to_fullpath, FILE* out,
  * If pgFile is not NULL then we must calculate crc and read_size for it.
  */
 int
-fio_send_file(const char *from_fullpath, const char *to_fullpath, FILE* out,
+fio_send_file(const char *from_fullpath, FILE* out, bool cut_zero_tail,
 												pgFile *file, char **errormsg)
 {
 	fio_header hdr;
 	int exit_code = SEND_OK;
 	size_t path_len = strlen(from_fullpath) + 1;
 	char *buf = pgut_malloc(CHUNK_SIZE);    /* buffer */
+	send_file_state st = {false, 0, 0, 0};
+
+	memset(&hdr, 0, sizeof(hdr));
+
+	if (file)
+	{
+		st.calc_crc = true;
+		st.crc = file->crc;
+	}
 
 	hdr.cop = FIO_SEND_FILE;
 	hdr.size = path_len;
@@ -2640,6 +2752,37 @@ fio_send_file(const char *from_fullpath, const char *to_fullpath, FILE* out,
 
 		if (hdr.cop == FIO_SEND_FILE_EOF)
 		{
+			if (st.write_size < st.read_size)
+			{
+				/*
+				 * We still need to calc crc for zero tail.
+				 */
+				fio_send_file_crc(&st, NULL, 0);
+
+				if (!cut_zero_tail)
+				{
+					/*
+					 * Let's write single zero byte to the end of file to restore
+					 * logical size.
+					 * Well, it would be better to use ftruncate here actually,
+					 * but then we need to change interface.
+					 */
+					st.read_size -= 1;
+					buf[0] = 0;
+					if (!fio_send_file_write(out, &st, buf, 1))
+					{
+						exit_code = WRITE_FAILED;
+						break;
+					}
+				}
+			}
+
+			if (file)
+			{
+				file->crc = st.crc;
+				file->read_size = st.read_size;
+				file->write_size = st.write_size;
+			}
 			break;
 		}
 		else if (hdr.cop == FIO_ERROR)
@@ -2660,17 +2803,23 @@ fio_send_file(const char *from_fullpath, const char *to_fullpath, FILE* out,
 			IO_CHECK(fio_read_all(fio_stdin, buf, hdr.size), hdr.size);
 
 			/* We have received a chunk of data data, lets write it out */
-			if (fwrite(buf, 1, hdr.size, out) != hdr.size)
+			fio_send_file_crc(&st, buf, hdr.size);
+			if (!fio_send_file_write(out, &st, buf, hdr.size))
 			{
 				exit_code = WRITE_FAILED;
 				break;
 			}
+		}
+		else if (hdr.cop == FIO_PAGE_ZERO)
+		{
+			Assert(hdr.size == 0);
+			Assert(hdr.arg <= CHUNK_SIZE);
 
-			if (file)
-			{
-				file->read_size += hdr.size;
-				COMP_FILE_CRC32(true, file->crc, buf, hdr.size);
-			}
+			/*
+			 * We have received a chunk of zero data, lets just think we
+			 * wrote it.
+			 */
+			st.read_size += hdr.arg;
 		}
 		else
 		{
@@ -2686,6 +2835,128 @@ fio_send_file(const char *from_fullpath, const char *to_fullpath, FILE* out,
 	return exit_code;
 }
 
+int
+fio_send_file_local(const char *from_fullpath, FILE* out, bool cut_zero_tail,
+			  pgFile *file, char **errormsg)
+{
+	FILE* in;
+	char* buf;
+	size_t read_len, non_zero_len;
+	int exit_code = SEND_OK;
+	send_file_state st = {false, 0, 0, 0};
+
+	if (file)
+	{
+		st.calc_crc = true;
+		st.crc = file->crc;
+	}
+
+	/* open source file for read */
+	in = fopen(from_fullpath, PG_BINARY_R);
+	if (in == NULL)
+	{
+		/* maybe deleted, it's not error in case of backup */
+		if (errno == ENOENT)
+			return FILE_MISSING;
+
+
+		*errormsg = psprintf("Cannot open file \"%s\": %s", from_fullpath,
+			 strerror(errno));
+		return OPEN_FAILED;
+	}
+
+	/* disable stdio buffering for local input/output files to avoid triple buffering */
+	setvbuf(in, NULL, _IONBF, BUFSIZ);
+	setvbuf(out, NULL, _IONBF, BUFSIZ);
+
+	/* allocate 64kB buffer */
+	buf = pgut_malloc(CHUNK_SIZE);
+
+	/* copy content and calc CRC */
+	for (;;)
+	{
+		read_len = fread(buf, 1, CHUNK_SIZE, in);
+
+		if (ferror(in))
+		{
+			*errormsg = psprintf("Cannot read from file \"%s\": %s",
+								 from_fullpath, strerror(errno));
+			exit_code = READ_FAILED;
+			goto cleanup;
+		}
+
+		if (read_len > 0)
+		{
+			non_zero_len = find_zero_tail(buf, read_len);
+			/*
+			 * It is dirty trick to silence warnings in CFS GC process:
+			 * backup at least cfs header size bytes.
+			 */
+			if (st.read_size + non_zero_len < PAGE_ZEROSEARCH_FINE_GRANULARITY &&
+				st.read_size + read_len > 0)
+			{
+				non_zero_len = Min(PAGE_ZEROSEARCH_FINE_GRANULARITY,
+								   st.read_size + read_len);
+				non_zero_len -= st.read_size;
+			}
+			if (non_zero_len > 0)
+			{
+				fio_send_file_crc(&st, buf, non_zero_len);
+				if (!fio_send_file_write(out, &st, buf, non_zero_len))
+				{
+					exit_code = WRITE_FAILED;
+					goto cleanup;
+				}
+			}
+			if (non_zero_len < read_len)
+			{
+				/* Just pretend we wrote it. */
+				st.read_size += read_len - non_zero_len;
+			}
+		}
+
+		if (feof(in))
+			break;
+	}
+
+	if (st.write_size < st.read_size)
+	{
+		/*
+		 * We still need to calc crc for zero tail.
+		 */
+		fio_send_file_crc(&st, NULL, 0);
+
+		if (!cut_zero_tail)
+		{
+			/*
+			 * Let's write single zero byte to the end of file to restore
+			 * logical size.
+			 * Well, it would be better to use ftruncate here actually,
+			 * but then we need to change interface.
+			 */
+			st.read_size -= 1;
+			buf[0] = 0;
+			if (!fio_send_file_write(out, &st, buf, 1))
+			{
+				exit_code = WRITE_FAILED;
+				goto cleanup;
+			}
+		}
+	}
+
+	if (file)
+	{
+		file->crc = st.crc;
+		file->read_size = st.read_size;
+		file->write_size = st.write_size;
+	}
+
+cleanup:
+	free(buf);
+	fclose(in);
+	return exit_code;
+}
+
 /* Send file content
  * On error we return FIO_ERROR message with following codes
  *  FIO_ERROR:
@@ -2746,6 +3017,7 @@ fio_send_file_impl(int out, char const* path)
 	for (;;)
 	{
 		read_len = fread(buf, 1, CHUNK_SIZE, fp);
+		memset(&hdr, 0, sizeof(hdr));
 
 		/* report error */
 		if (ferror(fp))
@@ -2766,10 +3038,22 @@ fio_send_file_impl(int out, char const* path)
 		if (read_len > 0)
 		{
 			/* send chunk */
-			hdr.cop = FIO_PAGE;
-			hdr.size = read_len;
-			IO_CHECK(fio_write_all(out, &hdr, sizeof(hdr)), sizeof(hdr));
-			IO_CHECK(fio_write_all(out, buf, read_len), read_len);
+			size_t non_zero_len = find_zero_tail(buf, read_len);
+			if (non_zero_len > 0)
+			{
+				hdr.cop = FIO_PAGE;
+				hdr.size = non_zero_len;
+				IO_CHECK(fio_write_all(out, &hdr, sizeof(hdr)), sizeof(hdr));
+				IO_CHECK(fio_write_all(out, buf, non_zero_len), non_zero_len);
+			}
+
+			if (non_zero_len < read_len)
+			{
+				hdr.cop = FIO_PAGE_ZERO;
+				hdr.size = 0;
+				hdr.arg = read_len - non_zero_len;
+				IO_CHECK(fio_write_all(out, &hdr, sizeof(hdr)), sizeof(hdr));
+			}
 		}
 
 		if (feof(fp))
diff --git a/src/utils/file.h b/src/utils/file.h
index ec478b451..3c01d07b5 100644
--- a/src/utils/file.h
+++ b/src/utils/file.h
@@ -56,7 +56,8 @@ typedef enum
 	FIO_CHECK_POSTMASTER,
 	FIO_GET_ASYNC_ERROR,
 	FIO_WRITE_ASYNC,
-	FIO_READLINK
+	FIO_READLINK,
+	FIO_PAGE_ZERO
 } fio_operations;
 
 typedef enum
diff --git a/src/validate.c b/src/validate.c
index 4044ac158..17ec9de1a 100644
--- a/src/validate.c
+++ b/src/validate.c
@@ -340,6 +340,14 @@ pgBackupValidateFiles(void *arg)
 				strcmp(file->name, "pg_control") == 0 &&
 				!file->external_dir_num)
 				crc = get_pgcontrol_checksum(arguments->base_path);
+			else if (!file->is_datafile &&
+					 file->uncompressed_size > file->write_size)
+			{
+				Assert(file->forkName == cfm);
+				Assert(arguments->backup_version >= 20509);
+				crc = pgFileGetCRCForTruncated(
+						file_fullpath, true, file->uncompressed_size);
+			}
 			else
 				crc = pgFileGetCRC(file_fullpath,
 								   arguments->backup_version <= 20021 ||
diff --git a/tests/cfs_backup.py b/tests/cfs_backup.py
index 436db31e7..861c9f1ea 100644
--- a/tests/cfs_backup.py
+++ b/tests/cfs_backup.py
@@ -171,12 +171,16 @@ def test_fullbackup_after_create_table(self):
             "ERROR: File pg_compression not found in {0}".format(
                 os.path.join(self.backup_dir, 'node', backup_id))
         )
-        self.assertTrue(
-            find_by_extensions(
-                [os.path.join(self.backup_dir, 'backups', 'node', backup_id)],
-                ['.cfm']),
-            "ERROR: .cfm files not found in backup dir"
-        )
+        cfms = find_by_extensions(
+            [os.path.join(self.backup_dir, 'backups', 'node', backup_id)],
+            ['.cfm'])
+        self.assertTrue(cfms, "ERROR: .cfm files not found in backup dir")
+        for cfm in cfms:
+            size = os.stat(cfm).st_size
+            self.assertLessEqual(size, 4096,
+                            "ERROR: {0} is not truncated (has size {1} > 4096)".format(
+                                cfm, size
+                            ))
 
     # @unittest.expectedFailure
     # @unittest.skip("skip")
diff --git a/tests/expected/option_version.out b/tests/expected/option_version.out
index 4de288907..7c9fcbfe0 100644
--- a/tests/expected/option_version.out
+++ b/tests/expected/option_version.out
@@ -1 +1 @@
-pg_probackup 2.5.8
+pg_probackup 2.5.9