diff --git a/src/aiori-S3-libs3.c b/src/aiori-S3-libs3.c
index 7d5bfb1..2267c53 100644
--- a/src/aiori-S3-libs3.c
+++ b/src/aiori-S3-libs3.c
@@ -1,5 +1,7 @@
 /*
 * S3 implementation using the newer libs3
+* https://github.com/bji/libs3
+* Use one object per file chunk
 */
 
 #ifdef HAVE_CONFIG_H
@@ -27,14 +29,16 @@ static void s3_xfer_hints(aiori_xfer_hint_t * params){
 
 /************************** O P T I O N S *****************************/
 typedef struct {
-  int bucket_per_dir;
+  int bucket_per_file;
   char * access_key;
   char * secret_key;
   char * host;
   char * bucket_prefix;
   char * bucket_prefix_cur;
   char * locationConstraint;
+  char * authRegion;
 
+  int timeout;
   int dont_suffix;
   int s3_compatible;
   int use_ssl;
@@ -54,7 +58,7 @@ static option_help * S3_options(aiori_mod_opt_t ** init_backend_options, aiori_m
   o->bucket_prefix = "ior";
 
   option_help h [] = {
-  //{0, "S3.bucket-per-directory", "Use one bucket to map one dir, otherwise only one bucket is used.", OPTION_FLAG, 'd', & o->bucket_per_dir},
+  {0, "S3.bucket-per-file", "Use one bucket to map one file, otherwise only one bucket is used to store all files.", OPTION_FLAG, 'd', & o->bucket_per_file},
   {0, "S3.bucket-name-prefix", "The name of the bucket (when using without -b), otherwise it is used as prefix.", OPTION_OPTIONAL_ARGUMENT, 's', & o->bucket_prefix},
   {0, "S3.dont-suffix-bucket", "If not selected, then a hash will be added to the bucket name to increase uniqueness.", OPTION_FLAG, 'd', & o->dont_suffix },
   {0, "S3.s3-compatible", "to be selected when using S3 compatible storage", OPTION_FLAG, 'd', & o->s3_compatible },
@@ -84,7 +88,7 @@ static void def_file_name(s3_options_t * o, char * out_name, char const * path){
 
 static void def_bucket_name(s3_options_t * o, char * out_name, char const * path){
   // S3_MAX_BUCKET_NAME_SIZE
-  if (o->bucket_per_dir){
+  if (o->bucket_per_file){
     out_name += sprintf(out_name, "%s-", o->bucket_prefix_cur);
   }
 
@@ -103,7 +107,7 @@ static void def_bucket_name(s3_options_t * o, char * out_name, char const * path
 }
 
 struct data_handling{
-  char * buf;
+  IOR_size_t * buf;
   int64_t size;
 };
 
@@ -126,24 +130,10 @@ static void responseCompleteCallback(S3Status status, const S3ErrorDetails *erro
 }
 
 #define CHECK_ERROR if (s3status != S3StatusOK){ \
-  EWARNF("S3 \"%s\": %s - %s", S3_get_status_name(s3status), s3error.message, s3error.furtherDetails); \
+  EWARNF("S3 %s:%d \"%s\": %s - %s", __FUNCTION__, __LINE__, S3_get_status_name(s3status), s3error.message, s3error.furtherDetails); \
 }
 
 
-static int putObjectDataCallback(int bufferSize, char *buffer, void *callbackData){
-  printf("CALLBACK\n");
-  struct data_handling * dh = (struct data_handling *) callbackData;
-  const int64_t size = dh->size > bufferSize ? bufferSize : dh->size;
-  if(size == 0) return 0;
-  memcpy(buffer, dh->buf, size);
-  dh->buf += size;
-  dh->size -= size;
-
-  return size;
-}
-
-static S3PutObjectHandler putObjectHandler = { {  &responsePropertiesCallback, &responseCompleteCallback }, & putObjectDataCallback };
-
 static S3ResponseHandler responseHandler = {  &responsePropertiesCallback, &responseCompleteCallback };
 
 static char * S3_getVersion()
@@ -180,79 +170,54 @@ static int S3_statfs (const char * path, ior_aiori_statfs_t * stat, aiori_mod_op
 
   // use the number of bucket as files
   uint64_t buckets = 0;
-  S3_list_service(o->s3_protocol, o->access_key, o->secret_key, o->host,
-    NULL, & listhandler, & buckets);
+  S3_list_service(o->s3_protocol, o->access_key, o->secret_key, NULL, o->host,
+    o->authRegion, NULL, o->timeout, & listhandler, & buckets);
   stat->f_files = buckets;
   CHECK_ERROR
 
   return 0;
 }
 
-static aiori_fd_t *S3_Create(char *testFileName, int iorflags, aiori_mod_opt_t * options)
-{
-  s3_options_t * o = (s3_options_t*) options;
-
-  return (aiori_fd_t*) 1;
+static S3Status S3multipart_handler(const char *upload_id, void *callbackData){
+  *((char const**)(callbackData)) = upload_id;
+  return S3StatusOK;
 }
 
-static aiori_fd_t *S3_Open(char *testFileName, int flags, aiori_mod_opt_t * options)
-{
-  s3_options_t * o = (s3_options_t*) options;
+static S3MultipartInitialHandler multipart_handler = { {&responsePropertiesCallback, &responseCompleteCallback }, & S3multipart_handler};
 
-  return (aiori_fd_t*) 1;
+typedef struct{
+  char * object;
+} S3_fd_t;
+
+static int putObjectDataCallback(int bufferSize, char *buffer, void *callbackData){
+  struct data_handling * dh = (struct data_handling *) callbackData;
+  const int64_t size = dh->size > bufferSize ? bufferSize : dh->size;
+  if(size == 0) return 0;
+  memcpy(buffer, dh->buf, size);
+  dh->buf = (IOR_size_t*) ((char*)(dh->buf) + size);
+  dh->size -= size;
+
+  return size;
 }
 
-static void S3_Close(aiori_fd_t *fd, aiori_mod_opt_t * options)
-{
-}
+static S3PutObjectHandler putObjectHandler = { {  &responsePropertiesCallback, &responseCompleteCallback }, & putObjectDataCallback };
 
-static void S3_Delete(char *path, aiori_mod_opt_t * options)
+static aiori_fd_t *S3_Create(char *path, int iorflags, aiori_mod_opt_t * options)
 {
+  char * upload_id;
   s3_options_t * o = (s3_options_t*) options;
   char p[FILENAME_MAX];
   def_file_name(o, p, path);
-  S3_delete_object(& o->bucket_context, p, NULL, & responseHandler, NULL);
-  CHECK_ERROR
-}
+  S3_fd_t * fd = malloc(sizeof(S3_fd_t));
+  fd->object = strdup(p);
 
-static IOR_offset_t S3_Xfer(int access, aiori_fd_t *file, IOR_size_t * buffer, IOR_offset_t length, IOR_offset_t offset, aiori_mod_opt_t * options){
-
-  return length;
-}
-
-static int S3_mkdir (const char *path, mode_t mode, aiori_mod_opt_t * options){
-  s3_options_t * o = (s3_options_t*) options;
-  char p[FILENAME_MAX];
-
-  def_bucket_name(o, p, path);
-  if (o->bucket_per_dir){
-    S3_create_bucket(o->s3_protocol, o->access_key, o->secret_key, NULL, p, S3CannedAclPrivate, o->locationConstraint, NULL,  & responseHandler, NULL);
-    CHECK_ERROR
-    return 0;
-  }else{
+  if(iorflags & IOR_CREAT){
     struct data_handling dh = { .buf = NULL, .size = 0 };
-    S3_put_object(& o->bucket_context, p, 0, NULL, NULL, & putObjectHandler, & dh);
-    if (! o->s3_compatible){
-      CHECK_ERROR
-    }
-    return 0;
-  }
-}
-
-static int S3_rmdir (const char *path, aiori_mod_opt_t * options){
-  s3_options_t * o = (s3_options_t*) options;
-  char p[FILENAME_MAX];
-
-  def_bucket_name(o, p, path);
-  if (o->bucket_per_dir){
-    S3_delete_bucket(o->s3_protocol, S3UriStylePath, o->access_key, o->secret_key, NULL, p, NULL,  & responseHandler, NULL);
+    S3_put_object(& o->bucket_context, p, 0, NULL, NULL, o->timeout, &putObjectHandler, & dh);
     CHECK_ERROR
-    return 0;
-  }else{
-    S3_delete_object(& o->bucket_context, p, NULL, & responseHandler, NULL);
-    CHECK_ERROR
-    return 0;
   }
+
+  return (aiori_fd_t*) fd;
 }
 
 
@@ -269,25 +234,135 @@ static S3Status statResponsePropertiesCallback(const S3ResponseProperties *prope
 
 static S3ResponseHandler statResponseHandler = {  &statResponsePropertiesCallback, &responseCompleteCallback };
 
+static aiori_fd_t *S3_Open(char *path, int flags, aiori_mod_opt_t * options)
+{
+  if(flags & IOR_CREAT){
+    return S3_Create(path, flags, options);
+  }
+  if(flags & IOR_WRONLY){
+    WARN("S3 IOR_WRONLY is not supported");
+  }
+  if(flags & IOR_RDWR){
+    WARN("S3 IOR_RDWR is not supported");
+  }
+
+  s3_options_t * o = (s3_options_t*) options;
+  char p[FILENAME_MAX];
+  def_file_name(o, p, path);
+
+  struct stat buf;
+  S3_head_object(& o->bucket_context, p, NULL, o->timeout, & statResponseHandler, & buf);
+  if (s3status != S3StatusOK){
+    return NULL;
+  }
+
+  S3_fd_t * fd = malloc(sizeof(S3_fd_t));
+  fd->object = strdup(p);
+
+  return (aiori_fd_t*) fd;
+}
+
+static S3Status getObjectDataCallback(int bufferSize, const char *buffer,  void *callbackData){
+  struct data_handling * dh = (struct data_handling *) callbackData;
+  const int64_t size = dh->size > bufferSize ? bufferSize : dh->size;
+  memcpy(dh->buf, buffer, size);
+  dh->buf = (IOR_size_t*) ((char*)(dh->buf) + size);
+  dh->size -= size;
+
+  return S3StatusOK;
+}
+
+static S3GetObjectHandler getObjectHandler = { {  &responsePropertiesCallback, &responseCompleteCallback }, & getObjectDataCallback };
+
+static IOR_offset_t S3_Xfer(int access, aiori_fd_t * afd, IOR_size_t * buffer, IOR_offset_t length, IOR_offset_t offset, aiori_mod_opt_t * options){
+  S3_fd_t * fd = (S3_fd_t *) afd;
+  struct data_handling dh = { .buf = buffer, .size = length };
+
+  s3_options_t * o = (s3_options_t*) options;
+  char p[FILENAME_MAX];
+  sprintf(p, "%s-%ld-%ld", fd->object, (long) offset, (long) length);
+  if(access == WRITE){
+    S3_put_object(& o->bucket_context, p, length, NULL, NULL, o->timeout, &putObjectHandler, & dh);
+  }else{
+    S3_get_object(& o->bucket_context, p, NULL, 0, length, NULL, o->timeout, &getObjectHandler, & dh);
+  }
+  if (! o->s3_compatible){
+    CHECK_ERROR
+  }
+  return length;
+}
+
+
+static void S3_Close(aiori_fd_t * afd, aiori_mod_opt_t * options)
+{
+  S3_fd_t * fd = (S3_fd_t *) afd;
+  free(fd->object);
+  free(afd);
+}
+
+static void S3_Delete(char *path, aiori_mod_opt_t * options)
+{
+  s3_options_t * o = (s3_options_t*) options;
+  char p[FILENAME_MAX];
+  def_file_name(o, p, path);
+  S3_delete_object(& o->bucket_context, p, NULL, o->timeout, & responseHandler, NULL);
+  CHECK_ERROR
+}
+
+static int S3_mkdir (const char *path, mode_t mode, aiori_mod_opt_t * options){
+  s3_options_t * o = (s3_options_t*) options;
+  char p[FILENAME_MAX];
+
+  def_bucket_name(o, p, path);
+  if (o->bucket_per_file){
+    S3_create_bucket(o->s3_protocol, o->access_key, o->secret_key, NULL, o->host, p, o->authRegion, S3CannedAclPrivate, o->locationConstraint, NULL, o->timeout, & responseHandler, NULL);
+    CHECK_ERROR
+    return 0;
+  }else{
+    struct data_handling dh = { .buf = NULL, .size = 0 };
+    S3_put_object(& o->bucket_context, p, 0, NULL, NULL, o->timeout, & putObjectHandler, & dh);
+    if (! o->s3_compatible){
+      CHECK_ERROR
+    }
+    return 0;
+  }
+}
+
+static int S3_rmdir (const char *path, aiori_mod_opt_t * options){
+  s3_options_t * o = (s3_options_t*) options;
+  char p[FILENAME_MAX];
+
+  def_bucket_name(o, p, path);
+  if (o->bucket_per_file){
+    S3_delete_bucket(o->s3_protocol, S3UriStylePath, o->access_key, o->secret_key, NULL, o->host, p, o->authRegion, NULL,  o->timeout, & responseHandler, NULL);
+    CHECK_ERROR
+    return 0;
+  }else{
+    S3_delete_object(& o->bucket_context, p, NULL, o->timeout, & responseHandler, NULL);
+    CHECK_ERROR
+    return 0;
+  }
+}
+
 static int S3_access (const char *path, int mode, aiori_mod_opt_t * options){
   s3_options_t * o = (s3_options_t*) options;
   char p[FILENAME_MAX];
   def_file_name(o, p, path);
 
-  S3_head_object(& o->bucket_context, p, NULL, & statResponseHandler, NULL);
+  S3_head_object(& o->bucket_context, p, NULL, o->timeout, & statResponseHandler, NULL);
   if (s3status != S3StatusOK){
     return -1;
   }
   return 0;
 }
 
-static int S3_stat (const char *path, struct stat *buf, aiori_mod_opt_t * options){
+static int S3_stat(const char *path, struct stat *buf, aiori_mod_opt_t * options){
   s3_options_t * o = (s3_options_t*) options;
   char p[FILENAME_MAX];
   def_file_name(o, p, path);
 
   memset(buf, 0, sizeof(struct stat));
-  S3_head_object(& o->bucket_context, p, NULL, & statResponseHandler, buf);
+  S3_head_object(& o->bucket_context, p, NULL, o->timeout, & statResponseHandler, buf);
   if (s3status != S3StatusOK){
     return -1;
   }
@@ -303,12 +378,18 @@ static IOR_offset_t S3_GetFileSize(aiori_mod_opt_t * options, char *testFileName
 
 
 static int S3_check_params(aiori_mod_opt_t * options){
+  if(hints->blockSize != hints->transferSize){
+    ERR("S3 Blocksize must be transferSize");
+  }
+
   return 0;
 }
 
 static void S3_init(aiori_mod_opt_t * options){
   s3_options_t * o = (s3_options_t*) options;
   int ret = S3_initialize(NULL, S3_INIT_ALL, o->host);
+  if(ret != S3StatusOK)
+    FAIL("Could not initialize S3 library");
 
   // create a bucket id based on access-key using a trivial checksumming
   if(! o->dont_suffix){
@@ -329,8 +410,8 @@ static void S3_init(aiori_mod_opt_t * options){
   memset(& o->bucket_context, 0, sizeof(o->bucket_context));
   o->bucket_context.hostName = o->host;
   o->bucket_context.bucketName = o->bucket_prefix_cur;
-  if (! o->bucket_per_dir){
-    S3_create_bucket(o->s3_protocol, o->access_key, o->secret_key, NULL, o->bucket_context.bucketName, S3CannedAclPrivate, o->locationConstraint, NULL,  & responseHandler, NULL);
+  if (! o->bucket_per_file){
+    S3_create_bucket(o->s3_protocol, o->access_key, o->secret_key, NULL, o->host, o->bucket_context.bucketName, o->authRegion, S3CannedAclPrivate, o->locationConstraint, NULL, o->timeout, & responseHandler, NULL);
     CHECK_ERROR
   }
 
diff --git a/testing/s3.sh b/testing/s3.sh
index d1bf50b..2e79e29 100755
--- a/testing/s3.sh
+++ b/testing/s3.sh
@@ -5,20 +5,23 @@
 ROOT="$(dirname ${BASH_SOURCE[0]})"
 TYPE="basic"
 
-cd $ROOT
-
-if [[ ! -e minio ]] ; then
+if [[ ! -e $ROOT/minio ]] ; then
   wget https://dl.min.io/server/minio/release/linux-amd64/minio
-  chmod +x minio
+  mv minio $ROOT
+  chmod +x $ROOT/minio
 fi
 
 export MINIO_ACCESS_KEY=accesskey
 export MINIO_SECRET_KEY=secretkey
 
-./minio --quiet server /dev/shm &
+$ROOT/minio --quiet server /dev/shm &
 
+export IOR_EXTRA="-o test"
+export MDTEST_EXTRA="-d test"
 source $ROOT/test-lib.sh
-IOR 2 -a S3-libs3 --S3.host=localhost:9000  --S3.secret-key=secretkey --S3.access-key=accesskey 
-MDTEST 2 -a S3-libs3 --S3.host=localhost:9000  --S3.secret-key=secretkey --S3.access-key=accesskey 
+
+I=100 # Start with this ID
+IOR 2 -a S3-libs3 --S3.host=localhost:9000  --S3.secret-key=secretkey --S3.access-key=accesskey -b $((10*1024*1024)) -t $((10*1024*1024))
+MDTEST 2 -a S3-libs3 --S3.host=localhost:9000  --S3.secret-key=secretkey --S3.access-key=accesskey
 
 kill -9 %1
diff --git a/testing/test-lib.sh b/testing/test-lib.sh
index 444873d..e35b245 100644
--- a/testing/test-lib.sh
+++ b/testing/test-lib.sh
@@ -40,7 +40,7 @@ I=0
 function IOR(){
   RANKS=$1
   shift
-  WHAT="${IOR_MPIRUN} $RANKS ${IOR_BIN_DIR}/ior ${@} ${IOR_EXTRA} -o ${IOR_TMP}/ior"
+  WHAT="${IOR_MPIRUN} $RANKS ${IOR_BIN_DIR}/ior ${@} -o ${IOR_TMP}/ior ${IOR_EXTRA}"
   $WHAT 1>"${IOR_OUT}/test_out.$I" 2>&1
   if [[ $? != 0 ]]; then
     echo -n "ERR"
@@ -56,7 +56,7 @@ function MDTEST(){
   RANKS=$1
   shift
   rm -rf ${IOR_TMP}/mdest
-  WHAT="${IOR_MPIRUN} $RANKS ${IOR_BIN_DIR}/mdtest ${@} ${MDTEST_EXTRA} -d ${IOR_TMP}/mdest -V=4"
+  WHAT="${IOR_MPIRUN} $RANKS ${IOR_BIN_DIR}/mdtest ${@} -d ${IOR_TMP}/mdest ${MDTEST_EXTRA} -V=4"
   $WHAT 1>"${IOR_OUT}/test_out.$I" 2>&1
   if [[ $? != 0 ]]; then
     echo -n "ERR"