OpenVMS I64 version and ECO level?
MONITOR should show a range of 0 to 200% here. One bar, but longer, and shown in aggregate across all processors.
MONITOR is a system-wide performance tool, and generally ill-suited for per-application monitoring.
As for determining application performance, DECset Performance and Coverage Analyzer (PCA) is a choice, or otherwise, and use these tools to profile the code. Or embed your own performance-monitoring calls (and any debugging needed). There are some fairly simple tools around in base OpenVMS that can monitor program counter addresses; these are within ANALYZE /SYSTEM most usually.
One of the usual triggers for performance differences between Unix and OpenVMS applications involves differences in file I/O. Unix file I/O is different than OpenVMS; it tends to stay in memory, where OpenVMS I/O tends to write the data to disk. OpenVMS also has issues when file extent sizes are at their default values and when volumes of data are being written.
But I'm not going to particularly speculate further. Use DECset PCA or another tool, and find out where the code is spending its time.
Do use caution here with some of the Itanium processors -- including the 1.6 GHz series processors you have here -- as you can see the hyperthreads show up as processors, too. (IIRC, this hyperthreading isn't turned on by default.)
