diff --git a/pungi/media_split.py b/pungi/media_split.py
index 2a11ba80..a1e3f479 100644
--- a/pungi/media_split.py
+++ b/pungi/media_split.py
@@ -62,7 +62,7 @@ class MediaSplitter(object):
     possible minimum.
     """
     def __init__(self, media_size, compose=None):
-        self.media_size = convert_media_size(media_size)
+        self.media_size = media_size
         self.files = []  # to preserve order
         self.file_sizes = {}
         self.sticky_files = set()
@@ -75,7 +75,7 @@ class MediaSplitter(object):
 
         if old_size is not None and old_size != size:
             raise ValueError("File size mismatch; file: %s; sizes: %s vs %s" % (name, old_size, size))
-        if size > self.media_size:
+        if self.media_size and size > self.media_size:
             raise ValueError("File is larger than media size: %s" % name)
 
         self.files.append(name)
@@ -111,7 +111,7 @@ class MediaSplitter(object):
             name = all_files.pop(0)
             size = convert_file_size(self.file_sizes[name])
 
-            if not disks or disk["size"] + size > self.media_size:
+            if not disks or (self.media_size and disk["size"] + size > self.media_size):
                 disk = {"size": sticky_files_size, "files": sticky_files[:]}
                 disks.append(disk)
 
@@ -119,5 +119,10 @@ class MediaSplitter(object):
             disk["size"] += size
             total_size_single += size
         if self.compose:
-            self.compose.log_debug("MediaSplitter: free space on single media would be %s. Total size of single medium: %s." % (self.media_size - total_size_single, total_size_single))
+            if self.media_size:
+                self.compose.log_debug("MediaSplitter: free space on single media would be %s. "
+                                       "Total size of single medium: %s."
+                                       % (self.media_size - total_size_single, total_size_single))
+            else:
+                self.compose.log_debug("MediaSplitter: Total size of single medium: %s." % total_size_single)
         return disks
diff --git a/tests/test_media_split.py b/tests/test_media_split.py
index 91de8a6b..dec35a66 100644
--- a/tests/test_media_split.py
+++ b/tests/test_media_split.py
@@ -7,6 +7,7 @@ except ImportError:
     import unittest
 import os
 import sys
+import mock
 
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..'))
 
@@ -59,6 +60,20 @@ def bl(s):
 
 class MediaSplitterTestCase(unittest.TestCase):
 
+    def setUp(self):
+        self.compose = mock.Mock()
+
+    def assertFreeSpace(self, free, total):
+        self.assertEqual(
+            self.compose.mock_calls,
+            [mock.call.log_debug('MediaSplitter: free space on single media would be %s. '
+                                 'Total size of single medium: %s.' % (free, total))])
+
+    def assertUnlimited(self, total):
+        self.assertEqual(
+            self.compose.mock_calls,
+            [mock.call.log_debug('MediaSplitter: Total size of single medium: %s.' % total)])
+
     def test_sum_size(self):
         ms = media_split.MediaSplitter(bl(100))
         ms.add_file('first', bl(20))
@@ -87,15 +102,16 @@ class MediaSplitterTestCase(unittest.TestCase):
             ms.add_file('too-big', bl(300))
 
     def test_fit_on_one(self):
-        ms = media_split.MediaSplitter(bl(100))
+        ms = media_split.MediaSplitter(bl(100), compose=self.compose)
         ms.add_file('first', bl(20))
         ms.add_file('second', bl(30))
 
         self.assertEqual(ms.split(),
                          [{'files': ['first', 'second'], 'size': bl(50)}])
+        self.assertFreeSpace(bl(50), bl(50))
 
     def test_split_on_two_discs(self):
-        ms = media_split.MediaSplitter(bl(100))
+        ms = media_split.MediaSplitter(bl(100), compose=self.compose)
         ms.add_file('first', bl(25))
         ms.add_file('second', bl(40))
         ms.add_file('third', bl(80))
@@ -103,6 +119,7 @@ class MediaSplitterTestCase(unittest.TestCase):
         self.assertEqual(ms.split(),
                          [{'files': ['first', 'second'], 'size': bl(65)},
                           {'files': ['third'], 'size': bl(80)}])
+        self.assertFreeSpace(bl(100 - 25 - 40 - 80), bl(25 + 40 + 80))
 
     def test_split_with_sticky_file(self):
         ms = media_split.MediaSplitter(bl(100))
@@ -115,5 +132,16 @@ class MediaSplitterTestCase(unittest.TestCase):
                          [{'files': ['sticky', 'first', 'second'], 'size': bl(80)},
                           {'files': ['sticky', 'third'], 'size': bl(95)}])
 
+    def test_split_unlimited_media(self):
+        ms = media_split.MediaSplitter(None, compose=self.compose)
+        ms.add_file('first', bl(25))
+        ms.add_file('second', bl(40))
+        ms.add_file('third', bl(80))
+
+        self.assertEqual(ms.split(),
+                         [{'files': ['first', 'second', 'third'], 'size': bl(145)}])
+        self.assertUnlimited(bl(25 + 40 + 80))
+
+
 if __name__ == "__main__":
     unittest.main()