HADOOP-3805. Improve fuse-dfs write performance.

(Pete Wyckoff via zshao)



git-svn-id: https://svn.apache.org/repos/asf/hadoop/core/trunk@683392 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -221,6 +221,9 @@ Trunk (unreleased changes)
     HADOOP-3836. Fix TestMultipleOutputs to correctly clean up. (Alejandro 
     Abdelnur via acmurthy)
 
+    HADOOP-3805. Improve fuse-dfs write performance.
+    (Pete Wyckoff via zshao)
+
 Release 0.18.0 - Unreleased
 
   INCOMPATIBLE CHANGES

src/contrib/fuse-dfs/README

@@ -89,6 +89,7 @@ rw
 -ousetrash (should fuse dfs throw things in /Trash when deleting them)
 -onotrash (opposite of usetrash)
 -odebug (do not daemonize - aka -d in fuse speak)
+-obig_writes (use fuse big_writes option so as to allow better performance of writes on kernels >= 2.6.26)
 
 The defaults are:
 
@@ -124,7 +125,7 @@ RECOMMENDATIONS:
 
 1. From /bin, ln -s $HADOOP_HOME/contrib/fuse-dfs/fuse_dfs* .
 2. Always start with debug on so you can see if you are missing a classpath or something like that.
-
+3. use -obig_writes
 
 --------------------------------------------------------------------------------
 
@@ -132,7 +133,7 @@ PERFORMANCE:
 
 1. if you alias ls to ls --color=auto and try listing a directory with lots (over thousands) of files, expect it to be slow and at 10s of thousands, expect it to be very very slow.  This is because --color=auto causes ls to stat every file in the directory. Since fuse-dfs does not cache attribute entries when doing a readdir, this is very slow. see https://issues.apache.org/jira/browse/HADOOP-3797 
 
-2. Writes are approximately 33% slower than the DFSClient. TBD how to optimize this. see: https://issues.apache.org/jira/browse/HADOOP-3805
+2. Writes are approximately 33% slower than the DFSClient. TBD how to optimize this. see: https://issues.apache.org/jira/browse/HADOOP-3805 - try using -obig_writes and if on a >2.6.26 kernel, should perform much better since bigger writes implies less context switching.
 
 3. Reads are ~20-30% slower even with the read buffering. 
 

src/contrib/fuse-dfs/build.xml

@@ -72,7 +72,7 @@
     </exec>
   </target>
 
-  <target name="test" if="libhdfs-fuse">
+  <target name="test" if="fusedfs">
     <echo message="testing FuseDFS ..."/>
    <antcall target="hadoopbuildcontrib.test"> 
    </antcall>

src/contrib/fuse-dfs/src/Makefile.am

@@ -15,6 +15,7 @@
 #
 bin_PROGRAMS = fuse_dfs
 fuse_dfs_SOURCES = fuse_dfs.c
-AM_CPPFLAGS= -D_FILE_OFFSET_BITS=64 -I$(JAVA_HOME)/include -I$(HADOOP_HOME)/src/c++/libhdfs/ -I$(JAVA_HOME)/include/linux/ -D_FUSE_DFS_VERSION=\"$(PACKAGE_VERSION)\" -DPROTECTED_PATHS=\"$(PROTECTED_PATHS)\"
+AM_CPPFLAGS=  -D_FILE_OFFSET_BITS=64 -I$(JAVA_HOME)/include -I$(HADOOP_HOME)/src/c++/libhdfs/ -I$(JAVA_HOME)/include/linux/ -I$(FUSE_HOME)/include
+AM_CPPFLAGS+= -D_FUSE_DFS_VERSION=\"$(PACKAGE_VERSION)\"
 AM_LDFLAGS= -L$(HADOOP_HOME)/build/libhdfs -lhdfs -L$(FUSE_HOME)/lib -lfuse -L$(JAVA_HOME)/jre/lib/$(OS_ARCH)/server -ljvm
 

src/contrib/fuse-dfs/src/fuse_dfs.c

@@ -101,7 +101,7 @@ typedef struct dfs_fh_struct {
 /** keys for FUSE_OPT_ options */
 static void print_usage(const char *pname)
 {
-  fprintf(stdout,"USAGE: %s [debug] [--help] [--version] [protected=<colon_seped_list_of_paths] [rw] [notrash] [usetrash] [private (single user)] [ro] server=<hadoop_servername> port=<hadoop_port> [entry_timeout=<secs>] [attribute_timeout=<secs>] <mntpoint> [fuse options]\n",pname);
+  fprintf(stdout,"USAGE: %s [debug] [--help] [--version] [-oprotected=<colon_seped_list_of_paths] [rw] [-onotrash] [-ousetrash] [-obig_writes] [-oprivate (single user)] [ro] [-oserver=<hadoop_servername>] [-oport=<hadoop_port>] [-oentry_timeout=<secs>] [-oattribute_timeout=<secs>] <mntpoint> [fuse options]\n",pname);
   fprintf(stdout,"NOTE: debugging option for fuse is -debug\n");
 }
 
@@ -115,6 +115,7 @@ enum
     KEY_RO,
     KEY_RW,
     KEY_PRIVATE,
+    KEY_BIGWRITES,
     KEY_DEBUG,
   };
 
@@ -130,6 +131,7 @@ static struct fuse_opt dfs_opts[] =
     FUSE_OPT_KEY("private", KEY_PRIVATE),
     FUSE_OPT_KEY("ro", KEY_RO),
     FUSE_OPT_KEY("debug", KEY_DEBUG),
+    FUSE_OPT_KEY("big_writes", KEY_BIGWRITES),
     FUSE_OPT_KEY("rw", KEY_RW),
     FUSE_OPT_KEY("usetrash", KEY_USETRASH),
     FUSE_OPT_KEY("notrash", KEY_NOTRASH),
@@ -175,6 +177,11 @@ int dfs_options(void *data, const char *arg, int key,  struct fuse_args *outargs
     fuse_opt_add_arg(outargs, "-d");
     options.debug = 1;
     break;
+  case KEY_BIGWRITES:
+#ifdef FUSE_CAP_BIG_WRITES
+    fuse_opt_add_arg(outargs, "-obig_writes");
+#endif
+    break;
   default: {
     // try and see if the arg is a URI for DFS
     int tmp_port;

src/contrib/fuse-dfs/src/test/TestFuseDFS.java

@@ -57,7 +57,7 @@ public class TestFuseDFS extends TestCase {
     String lp = System.getProperty("LD_LIBRARY_PATH") + ":" + "/usr/local/lib:" + libhdfs + ":" + jvm;
     System.err.println("LD_LIBRARY_PATH=" + lp);
     String cmd[] =  {  fuse_cmd, "dfs://" + dfs.getHost() + ":" + String.valueOf(dfs.getPort()), 
-		       mountpoint, "-odebug", "-oentry_timeout=1",  "-oattribute_timeout=1", "-ousetrash", "rw" };
+		       mountpoint, "-obig_writes", "-odebug", "-oentry_timeout=1",  "-oattribute_timeout=1", "-ousetrash", "rw" };
     final String [] envp = {
       "CLASSPATH="+  cp,
       "LD_LIBRARY_PATH=" + lp,