Hello, I hope it is OK to post this. I have been investigating a problem seen on Dell R720(xd) hosts with PERC H710P Mini firmware 21.3.1-0004 or 21.3.2-0005, running RHEL 6.6 and 6.7. Interrupts are only seen on the first interrupt. The details are in https://bugzilla.redhat.com/show_bug.cgi?id=1361333 , I would appreciate any help in isolating the problem behaviour (I plan to see if we can downgrade the firmware as the next step), or if the bug is already known. Ruling out a problem with the megaraid driver and being able to demonstrate a problem with the firmware would help me when opening a support request with the hardware/firmware vendor. Thanks, Peter (Stig) Edwards Extract from https://bugzilla.redhat.com/show_bug.cgi?id=1361333 Description of problem: Interrupts for "IR-PCI-MSI-edge megasas" are only being seen (for some hosts) on one of the interrupts (the first). irqbalance will mask the interrupt to a CPU and so we see a single CPU can be saturated handling interrupts under a heavy IO load. Seen on these RHEL releases: RHEL6.6 2.6.32-573.12.1.el6.x86_64 RHEL6.7 2.6.32-642.3.1.el6.x86_64 Seen on a few hosts, Dell Poweredge R720 and R720xd with one or two E5-2630 v2 or a single E5-2680 0. Seen on Dell BIOS 2.2.2, 2.4.3, 2.5.2 and 2.5.4. Seen (and not seen) on hosts with identical BIOS and firmware versions, and identical ACPI tables, identical (basic) BIOS exposed by dmidecode and omreport. Seen when there are 16 vCPUs, 24vCPUs online. Seen when there are 48 possible CPUs. Seen when using irqbalance-1.0.7-8.el6 and with previous versions (where interrupt would be limit to first vCPU on a NUMA node). Controller is PERC H710P Mini (Embedded), seen on firmware 21.3.1-0004, 21.3.2-0005 and driver version 06.806.08.00-rh3, 06.810.09.00-rh1, not seen on firmware 21.2.0-0007 Version-Release number of selected component (if applicable): So far the common items are: .) RHEL6.7 or RHEL6.6 .) Dell R720 or R720xd .) 48 possible CPUs .) Dell BIOS version 2.2.2 or greater Every host with the problem has: .) PERC H710P Mini (Embedded) firmware 21.3.1-0004 or 21.3.2-0005 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
