After updating to 6.4 initially everything is OK, however after a while all disks attached to my SuperMicro AOC-SAS2LP-MV8 slow massively.  Disks attached to the motherboard directly are not affected.  The worst affected disks slow to 2 MB/sec read.  The least affected slow to 40 MB/sec.  After rebooting, everything is again OK for a short while before the problem returns.

 

I know this HBA card is listed as potentially having issues - specifically random parity errors upon reboot - but I have not observed this issue and so have continued to use it.

 

I am wondering, has support for this card been removed, or is there an issue?

 

Logs attached.

 

 

bigbox-diagnostics-20180116-1939.zip

IRQ16 got disabled:

 

Jan 16 19:32:21 BIGBOX kernel: irq 16: nobody cared (try booting with the "irqpoll" option)

 

Since it's used by the SAS2LP performance craters, possible solutions: look for a board bios update, use a different PCI slot for the HBA (if available), a kernel (unRAID) update may also help, but IMO the best option would be to replace it with an LSI.