How to use the Intel® Cluster Checker v3 SDK on a cluster using multiple Linux Distributions

Linux based HPC clusters can use different Linux distributions or different versions of a given Linux distribution for different types of nodes in the HPC cluster.

When the Linux distribution on which the connector extension has been built uses a glibc version 2.14 or newer and the Linux distribution where the connector extension is used, i.e. where clck-analyze is executed, uses a glibc version lower than 2.14, clck-analyze is not able to execute the shared library of the connector extension due to a missing symbol.

clck-analyze will show a message like this:

<your check>... not found

and

ldd lib<your check>.so

will show the following message, in addition to other output:

./lib<your check>.so: /lib64/libc.so.6: version `GLIBC_2.14' not found (required by ./lib<your check>.so)

The underlying reason is that memcpy is versioned by default as memcpy@GLIBC_2.14 starting in glibc version 2.14.
glibc versions lower than 2.14 will not have memcpy versioned like this.
The previous version, memcpy@GLIBC_2.2.5, is available in all glibc versions.

There are three solutions to this problem.

1. The preferred solution is to compile the connector extension, i.e. lib<your check>.so, on a Linux distribution using a glibc version lower than 2.14
2. If case option #1 cannot be used, you can enforce the use of the compatible memcpy@GLIBC_2.2.5 by adding the following code into the header file of your connector extension (as described here http://stackoverflow.com/questions/8823267/linking-against-older-symbol-version-in-a-so-file):

   #if defined(__GNUC__) && defined(__LP64__)  /* only with 64bit gcc, just to be sure */
   #include <features.h>       /* get the glibc version */
   /* only change memcpy when the version is newer than 2.14 */
   #if defined(__GLIBC__) && (__GLIBC__ == 2) && (__GLIBC_MINOR__ >= 14)
   /* enforce mempcy to use the earlier, i.e. compatible, memcpy@GLIBC_2.2.5 */
   __asm__(".symver memcpy,memcpy@GLIBC_2.2.5");
   #endif
   #undef _FEATURES_H  /* reload it ... usually necessary */
   #endif

3. The third solution is to use a wrapper function. This is also described on the above mentioned web page, but option #2 is simpler and easier to use.

Now you can compile your connector extension on a Linux distribution with a glibc version of 2.14 or newer and use it on a Linux distribution with a glibc version lower than 2.14.