test(mount): Add test for ignoreflush option (#229)

This change adds a test for checking the sfsignoreflush option
when a possible write process could fail during the flush
operation. This way it is possible to check that when
sfsignoreflush is on, some writing errors can be ignored.

doc/sfsmount.1.adoc

@@ -213,10 +213,10 @@ Equivalent to *--nostdopts* (*-n*) option for use in fstab.
 *-o nonempty*::
 Equivalent to *--nonempty* option for use in fstab.
 
-*-o sfsignoreflush*::
+*-o sfsignoreflush*'0|1'::
 Advanced: use with caution. Ignore flush usual behavior by replying SUCCESS to it
 immediately. Targets fast creation of small files, but may cause data loss
-during crashes when allegedly flushed data is still being processed.
+during crashes when allegedly flushed data is still being processed (default: 0).
 
 *-o sfsdirectio=*'0|1'::
 Whether to use FUSE DirectIO. This may improve performance when reading large

src/mount/fuse/mount_config.cc

@@ -92,7 +92,7 @@ struct fuse_opt gSfsOptsStage2[] = {
 	SFS_OPT("bandwidthoveruse=%lf", bandwidthoveruse, 1),
 	SFS_OPT("sfsdirentrycachesize=%u", direntrycachesize, 0),
 	SFS_OPT("nostdmountoptions", nostdmountoptions, 1),
-	SFS_OPT("sfsignoreflush", ignoreflush, 1),
+	SFS_OPT("sfsignoreflush=%d", ignoreflush, 0),
 
 	SFS_OPT("enablefilelocks=%u", filelocks, 0),
 	SFS_OPT("nonempty", nonemptymount, 1),
@@ -168,9 +168,10 @@ void usage(const char *progname) {
 "    -o sfswriteworkers=N        define number of write workers (default: %u)\n"
 "    -o sfswritewindowsize=N     define write window size (in blocks) for "
 				"each chunk (default: %u)\n"
-"    -o sfsignoreflush           Advanced: use with caution. Ignore flush usual "
+"    -o sfsignoreflush=0|1       Advanced: use with caution. Ignore flush usual "
 				"behavior by replying SUCCESS to it immediately. Targets fast "
-				"creation of small files, but may cause data loss during crashes.\n"
+				"creation of small files, but may cause data loss during crashes "
+				"(default: %d)\n"
 "\n"
 "Other options:\n"
 "    -m   --meta                 equivalent to '-o sfsmeta'\n"
@@ -248,6 +249,7 @@ void usage(const char *progname) {
 		SaunaClient::FsInitParams::kDefaultCachePerInodePercentage,
 		SaunaClient::FsInitParams::kDefaultWriteWorkers,
 		SaunaClient::FsInitParams::kDefaultWriteWindowSize,
+		SaunaClient::FsInitParams::kDefaultIgnoreFlush,
 		SaunaClient::FsInitParams::kDefaultUseRwLock,
 		SaunaClient::FsInitParams::kDefaultMkdirCopySgid,
 		sugidClearModeString(SaunaClient::FsInitParams::kDefaultSugidClearMode),

src/mount/writedata.cc

@@ -215,7 +215,6 @@ static InodeDataMap inodedataMap;
 
 static uint32_t gWriteWindowSize;
 static uint32_t gChunkserverTimeout_ms;
-static std::atomic<bool> gIgnoreFlush;
 
 // percentage of the free cache (1% - 100%) which can be used by one inode
 static uint32_t gCachePerInodePercentage;

tests/test_suites/SanityChecks/test_mount_tweaks.sh

@@ -6,8 +6,8 @@
 #
 MOUNTS=2 \
   USE_RAMDISK=YES \
-  MOUNT_0_EXTRA_CONFIG="sfsdirectio=0" \
-  MOUNT_1_EXTRA_CONFIG="sfsdirectio=1,sfsignoreflush" \
+  MOUNT_0_EXTRA_CONFIG="sfsdirectio=0,sfsignoreflush=0" \
+  MOUNT_1_EXTRA_CONFIG="sfsdirectio=1,sfsignoreflush=1" \
   setup_local_empty_saunafs info
 
 expect_equals "false" "$(cat ${info[mount0]}/.saunafs_tweaks | grep -i directio | awk '{print $2}')"

tests/test_suites/ShortSystemTests/test_ignore_flush.sh

@@ -0,0 +1,56 @@
+CHUNKSERVERS=5 \
+	MOUNTS=2 \
+	MOUNT_0_EXTRA_CONFIG="sfscachemode=NEVER`
+			`|sfsignoreflush=1`
+			`|sfsioretries=5" \
+	MOUNT_1_EXTRA_CONFIG="sfscachemode=NEVER`
+			`|sfsignoreflush=0`
+			`|sfsioretries=5" \
+	MASTER_CUSTOM_GOALS="10 ec_3_2: \$ec(3,2)" \
+	USE_RAMDISK=YES \
+	setup_local_empty_saunafs info
+
+get_checksum() {
+	sha256sum $1 | awk '{ print $1 }'
+}
+
+dir="${info[mount0]}/dir1"
+dir2="${info[mount1]}/dir2"
+
+mkdir "$dir" "$dir2"
+
+saunafs setgoal ec_3_2 "$dir" "$dir2"
+
+# stop three chunkservers for invalidating the writing of a ec_3_2 file
+for i in {0..2}; do
+	saunafs_chunkserver_daemon $i stop
+done
+
+assert_success dd if=/dev/zero of=${dir}/file1 bs=1M count=1 oflag=direct
+assert_failure dd if=/dev/zero of=${dir2}/file2 bs=1M count=1 oflag=direct
+
+# now test that with only two chunkservers stopped, 
+# writing the ec_3_2 files is possible
+saunafs_chunkserver_daemon 0 start
+
+dd if=/dev/urandom of=/tmp/tmpfile1 bs=1M count=100
+dd if=/dev/urandom of=/tmp/tmpfile2 bs=1M count=100
+
+checksum_tmp_file1=$(get_checksum /tmp/tmpfile1)
+checksum_tmp_file2=$(get_checksum /tmp/tmpfile2)
+
+echo "Copying files from /tmp to $dir and $dir2"
+assert_success dd if=/tmp/tmpfile1 of=${dir}/tmpfile1 oflag=direct bs=1M count=100
+assert_success dd if=/tmp/tmpfile2 of=${dir2}/tmpfile2 oflag=direct bs=1M count=100
+
+echo "Compare files to ensure they are identical"
+assert_success cmp /tmp/tmpfile1 ${dir}/tmpfile1
+assert_success cmp /tmp/tmpfile2 ${dir2}/tmpfile2
+
+echo "Get the md5sum of the files"
+checksum_dir_file1=$(get_checksum ${dir}/tmpfile1)
+checksum_dir_file2=$(get_checksum ${dir2}/tmpfile2)
+
+echo "Compare md5sums to ensure they are identical"
+assert_equals $checksum_tmp_file1 $checksum_dir_file1
+assert_equals $checksum_tmp_file2 $checksum_dir_file2