I have two identical Pegasus 2 R6 raid 5 systems attached directly to the new 2019 Mac Pro through a thunderbolt 3 cable with an Apple thunderbolt 3 to thunderbolt 2 adapter on both systems at the point of attachment to the Mac Pro thunderbolt 3 ports. Both of these Pegasus 2 systems have the same and latest firmware. Both are connected with thunderbolt cables supplied by Promise with the systems. I am using Mac OS Catalina with the latest udates and I am using the Mac OS Catalina compatible (latest) Promise Utility. Both of these Pegasus 2 R6 systems show a full green board in the Promise Utility. Both Pegasus 2 systems read and write fine, and I am experiening no disconnections or other problems. However , in the Black Magic Disk Speed test one of the Pegasus 2 R6 systems shows an excellent read/write valuse of roughly 800 and 700 MB/sec while the other Pegasus 2 R6 system shows a write speed of only about 150 Mb/sec and a read speed of about 500 MB/sec.
I am at a loss as to why there is such a vast difference in the write speed of these two identical Pegasus 2 systems. Both have only about 2TB out of their totoal 15 TB capacity so disk space is not an issue.
I would be most appreciative if anyone can tell me how to improve the write speed of the slower of these two Pegasus 2 R6 systems or explain what is likely going on here. Thank you in advance for responding.