diff --git a/hadoopy/_hdfs.py b/hadoopy/_hdfs.py
index fd08f14..95b9a98 100755
--- a/hadoopy/_hdfs.py
+++ b/hadoopy/_hdfs.py
@@ -33,9 +33,7 @@ def _cleaned_hadoop_stderr(hdfs_stderr):
             yield line
         
 
-def _hadoop_fs_command(cmd, stdin=None, stdout=subprocess.PIPE, stderr=subprocess.PIPE, java_mem_mb=100):
-    env = dict(os.environ)
-    env['HADOOP_OPTS'] = "-Xmx%dm" % java_mem_mb
+def _hadoop_fs_command(cmd, stdin=None, stdout=subprocess.PIPE, stderr=subprocess.PIPE):
     p = subprocess.Popen(cmd, env=env, shell=True, close_fds=True,
                          stdin=stdin,
                          stdout=stdout,
@@ -226,19 +224,18 @@ def ls(path):
     return out
 
 
-def writetb(path, kvs, java_mem_mb=256):
+def writetb(path, kvs):
     """Write typedbytes sequence file to HDFS given an iterator of KeyValue pairs
 
     :param path: HDFS path (string)
     :param kvs: Iterator of (key, value)
-    :param java_mem_mb: Integer of java heap size in MB (default 256)
     :raises: IOError: An error occurred while saving the data.
     """
     read_fd, write_fd = os.pipe()
     read_fp = os.fdopen(read_fd, 'r')
     hstreaming = _find_hstreaming()
     cmd = 'hadoop jar %s loadtb %s' % (hstreaming, path)
-    p = _hadoop_fs_command(cmd, stdin=read_fp, java_mem_mb=java_mem_mb)
+    p = _hadoop_fs_command(cmd, stdin=read_fp)
     read_fp.close()
     with hadoopy.TypedBytesFile(write_fd=write_fd) as tb_fp:
         for kv in kvs:
@@ -262,7 +259,6 @@ def writetb_parts(path, kvs, num_per_file, **kw):
     :param path: HDFS path (string)
     :param kvs: Iterator of (key, value)
     :param num_per_file: Max # of kv pairs per file.
-    :param java_mem_mb: Integer of java heap size in MB (default 256)
     :raises: IOError: An error occurred while saving the data.
     """
     out = []
@@ -279,7 +275,7 @@ def _flush(out, part_num):
         out, part_num = _flush(out, part_num)
 
 
-def readtb(paths, num_procs=1, java_mem_mb=256, ignore_logs=True):
+def readtb(paths, num_procs=1, ignore_logs=True):
     """Read typedbytes sequence files on HDFS (with optional compression).
 
     By default, ignores files who's names start with an underscore '_' as they
@@ -290,7 +286,6 @@ def readtb(paths, num_procs=1, java_mem_mb=256, ignore_logs=True):
 
     :param paths: HDFS path (str) or paths (iterator)
     :param num_procs: Number of reading procs to open (default 1)
-    :param java_mem_mb: Integer of java heap size in MB (default 256)
     :param ignore_logs: If True, ignore all files who's name starts with an underscore.  Defaults to True.
     :returns: An iterator of key, value pairs.
     :raises: IOError: An error occurred reading the directory (e.g., not available).
@@ -307,7 +302,7 @@ def _open_tb(cur_path):
         cmd = 'hadoop jar %s dumptb %s' % (hstreaming, cur_path)
         read_fd, write_fd = os.pipe()
         write_fp = os.fdopen(write_fd, 'w')
-        p = _hadoop_fs_command(cmd, stdout=write_fp, java_mem_mb=java_mem_mb)
+        p = _hadoop_fs_command(cmd, stdout=write_fp)
         write_fp.close()
         read_fds.add(read_fd)
         procs[read_fd] = p