Hi Jun:
Looks like it is not in the apache hadoop 1.x release binaries, this probably
will have to be answered by the apache hadoop 1.x release team
To build the native libs:
1) Get the source code and install the dependencies to compile hadoop
2) You'll have to setup the env for it, such as JAVA_HOME. Gcc installed
etc.
3) Got to <hadoop-source dir> ant [veryclean] compile-core-native
>compile.out
Verify with
[branch-1]$ objdump -Tt ./build/native/Linux-amd64-64/lib/libhadoop.so | grep
fadv
00000000000056a0 g F .text 00000000000000a3
Java_org_apache_hadoop_io_nativeio_NativeIO_posix_1fadvise
0000000000000000 F *UND* 0000000000000000
posix_fadvise@@GLIBC_2.2.5
0000000000000000 DF *UND* 0000000000000000 GLIBC_2.2.5 posix_fadvise
00000000000056a0 g DF .text 00000000000000a3 Base
Java_org_apache_hadoop_io_nativeio_NativeIO_posix_1fadvise
If you get an error about "make distclean" error
Just cd in src/native and run make distclean (to cleanup )
Example of ant output that shows checking for fadvise
[exec] checking for fcntl.h... yes
[exec] checking for stdlib.h... (cached) yes
[exec] checking for string.h... (cached) yes
[exec] checking for unistd.h... (cached) yes
[exec] checking for fcntl.h... (cached) yes
[exec] checking for posix_fadvise... yes
[exec] checking for fcntl.h... (cached) yes
[exec] checking for sync_file_range... yes
If you see "no" for posix_fadvise or "sync_file_range"
And you are sure you have posix_fdavise support (RHEL 6.x or CentOS 6.x)
you may need to move the section on src/native/configure.ac
Try to modify the configure.ac
--- src/native/configure.ac (revision 1495498)
+++ src/native/configure.ac (working copy)
@@ -47,6 +47,21 @@
AC_PROG_CC
AC_PROG_LIBTOOL
+dnl check for posix_fadvise
+AC_CHECK_HEADERS(fcntl.h, [AC_CHECK_FUNCS(posix_fadvise)])
+
+dnl check for sync_file_range
+AC_CHECK_HEADERS(fcntl.h, [AC_CHECK_FUNCS(sync_file_range)])
+
+# Checks for typedefs, structures, and compiler characteristics.
+AC_C_CONST
+
+# Checks for library functions.
+AC_CHECK_FUNCS([memset])
+
+# Check for nonstandard STRERROR_R
+AC_FUNC_STRERROR_R
+
# Checks for libraries.
dnl Check for '-ldl'
AC_CHECK_LIB([dl], [dlopen])
@@ -104,21 +119,6 @@
dnl Check for headers needed by the native Group resolution implementation
AC_CHECK_HEADERS([fcntl.h stdlib.h string.h unistd.h], [], AC_MSG_ERROR(Some
system headers not found... please ensure their presence on your platform.))
-dnl check for posix_fadvise
-AC_CHECK_HEADERS(fcntl.h, [AC_CHECK_FUNCS(posix_fadvise)])
-
-dnl check for sync_file_range
-AC_CHECK_HEADERS(fcntl.h, [AC_CHECK_FUNCS(sync_file_range)])
-
-# Checks for typedefs, structures, and compiler characteristics.
-AC_C_CONST
-
-# Checks for library functions.
-AC_CHECK_FUNCS([memset])
-
-# Check for nonstandard STRERROR_R
-AC_FUNC_STRERROR_R
-
AC_CONFIG_FILES([Makefile])
AC_OUTPUT
Hope this helps
From: Jun Li [mailto:[email protected]]
Sent: Friday, June 21, 2013 9:44 AM
To: [email protected]
Subject: Re: how to turn on NativeIO.posixFadviseIfPossible
Hi Leo,
Following your instruction, the following is what I got:
[junli@mercoop-26 Linux-amd64-64]$ objdump -Tt libhadoop.so | grep -I fadvise
0000000000004d70 g F .text 000000000000006f
Java_org_apache_hadoop_io_nativeio_NativeIO_posix_1fadvise
0000000000004d70 g DF .text 000000000000006f Base
Java_org_apache_hadoop_io_nativeio_NativeIO_posix_1fadvise
Apparently the part of "the GLIBC" is not there
The libhadoop.so is the one that I downloaded as part of the tar.gz of
hadoop.1.1.2 from the Hadoop Apache web site.
Could you let me know how I can use the source code directory in the downloaded
Hadoop Apache package, to re-compile the libhadoop.so and to make sure that the
fadvise call is able to get referenced?
Regards,
Jun
On Fri, Jun 21, 2013 at 9:19 AM, Leo Leung
<[email protected]<mailto:[email protected]>> wrote:
This looks like a compilation problem on the native hadoop libraries.
Please locate the libhadoop.so library on your system and run
[shell] objdump -Tt libhadoop.so | grep -I fadvise
If you don't see something like the following *the GLIBC* part (that means the
system where the share lib was compiled did not have it)
00000000000056a0 g F .text 00000000000000a3
Java_org_apache_hadoop_io_nativeio_NativeIO_posix_1fadvise
0000000000000000 F *UND* 0000000000000000
posix_fadvise@@GLIBC_2.2.5
0000000000000000 DF *UND* 0000000000000000 GLIBC_2.2.5 posix_fadvise
00000000000056a0 g DF .text 00000000000000a3 Base
Java_org_apache_hadoop_io_nativeio_NativeIO_posix_1fadvise
Note: objdump is from binutils- rpm (you can use yum install to install it if
you don't have it)
-----Original Message-----
From: Jun Li [mailto:[email protected]<mailto:[email protected]>]
Sent: Friday, June 21, 2013 1:35 AM
To: [email protected]<mailto:[email protected]>
Subject: how to turn on NativeIO.posixFadviseIfPossible
Hi,
I downloaded the current stable version from the Apache Hadoop web site,
hadoop-1.1.2. My machine is an AMD-based machine and Redhat Enterprise 6.1. The
detailed Linux kernel version is:
2.6.32-131.0.15.el6.x86_64
I ran the TestNativeIO.java under the distribution directory of
"test/org/apache/hadoop/io/nativeio/TestNativeIO.java" and tried to understand
how NativeIO.posixFadviseIfPossible behaves, in particular, to check whether
"posix_fadvise" is turned on or not. I am interested in this call as it is used
in Read-Ahead-Pool to cache data to the OS's buffer cache. The following is
the test case that I ran:
@Test
public void testPosixFadvise() throws Exception {
FileInputStream fis = new FileInputStream("/dev/zero");
try {
NativeIO.posixFadviseIfPossible(fis.getFD(), 0, 0,
NativeIO.POSIX_FADV_SEQUENTIAL);
} catch (NativeIOException noe) {
// we should just skip the unit test on machines where we don't
// have fadvise support
assumeTrue(false);
} finally {
fis.close();
}
However, when I stepped into the code and reached "NativeIO.java"
under the package of "org.apache.hadoop.io.nativeio", in the particular call
below:
public static void posixFadviseIfPossible(
FileDescriptor fd, long offset, long len, int flags)
throws NativeIOException {
if (nativeLoaded && fadvisePossible) {
try {
posix_fadvise(fd, offset, len, flags);
} catch (UnsupportedOperationException uoe) {
fadvisePossible = false;
} catch (UnsatisfiedLinkError ule) {
fadvisePossible = false;
}
}
}
The call to "posix_fadvise" threw the "UnsupportedOperationException"
exception.
I further traced to the native library, and in the code "NativeIO.c", I found
JNIEXPORT void JNICALL
Java_org_apache_hadoop_io_nativeio_NativeIO_posix_1fadvise(
JNIEnv *env, jclass clazz,
jobject fd_object, jlong offset, jlong len, jint flags) { #ifndef
HAVE_POSIX_FADVISE
THROW(env, "java/lang/UnsupportedOperationException",
"fadvise support not available"); #else
...
}
I believe that the problem of throwing the exception is because
"HAVE_POSIX_FADVISE" is not defined. I made sure that the native IO library is
loaded properly in the Java code, as I can successfully run the other test
cases in "TestNativeIO.java".
So my question is: should I re-compile the "libhadoop" in order to get the
version of the shared library that can have "HAVE_POSIX_FADVISE"
turned on? Or by default, FADVISE is turned on already?
Thank you!
