Greetings,
We've attached a J4200 array via a Sun PCI-E SAS HBA (SG-XPCIE8SAS-E-Z)
to a Sun V245. A small amount of write traffic to a ZFS pool on the J4200
is causing one of the V245's CPU's to be 100% busy handling mpt interrupts
for the HBA, according to "intrstat". By "small amount", I mean we're able
to get only as much as 2-4MB/second throughput from a simple:
dd if=/dev/zero of=/testpool/testfile bs=1024k count=1000 &
device | cpu0 %tim cpu1 %tim
-------------+------------------------------
bge#0 | 5 0.0 0 0.0
ehci#0 | 0 0.0 1 0.0
mpt#0 | 0 0.0 47 99.7
ohci#0 | 0 0.0 0 0.0
ohci#1 | 0 0.0 0 0.0
The system is running Solaris-10U7, patches are current as of a couple weeks
ago, and all firmware (V245, HBA, J4200, drives) is up to date.
This same server got pretty reasonable throughput using a Sun/Qlogic QLE2462
FC HBA connected to an old HDS 9520V array, and without the heavy interrupt
load, so something seems seriously awry with the current situation.
The LSI documentation for the HBA claims it is capable of interrupt
coalescing, which would seem beneficial for this setup. I've not found
much in the way of mpt driver, msi/msix, or other performance tuning
available for this HBA, so I'm hoping I'm missing something obvious.
Suggestions?
Thanks and regards,
Marion
_______________________________________________
storage-discuss mailing list
[email protected]
http://mail.opensolaris.org/mailman/listinfo/storage-discuss
