If you have upgraded NetBackup 188.8.131.52 with EEB ET 3256506, note the following issue:
Bpbkar crash dumps may occur on a VMware backup host even though the backups are successful. The dump files may occupy too much space and affect performance.
Crash dump shows bpbkar32 main thread sleeping while the crash occurs. Crashing thread has a stack going into vmacore.dll (VDDK). The crash is being caused by threads that are not being cleaned up by VDDK after the VixDiskLib_Exit call. When the VDDK plugin is loaded, several threads are started that cannot be shut down until the calling application exits. For instance on Windows Server 2008, VDDK libraries may leave threads running after the VixDiskLib_Exit call. Still-running threads are from the vCenter vmacore library and cannot be unloaded until the application finishes. The leftover threads should be harmless but, in some cases, the calling application can terminate unexpectedly.
Per the VDDK 5.5 release notes, this issue will be addressed in the first 5.5.x update release. The fix will address the logging attempts that were causing problems. Even with that fix, however, the threads will continue to run as before. Terminating the threads will not be addressed as of VDDK 5.5.x. For further information, consult VMWare Support.
Regarding this issue, it is important to note that backups are still successful and backup images are complete. However, as a workaround, the recommendation is to delete the crash dump files regularly or disable crash-dump generation within the OS to reduce disk space consumption.