On Fri, Apr 12, 2019, 1:22 PM Patrick M. Hausen <hau...@punkt.de> wrote:
> Hi Warner, > > thanks for taking the time again … > > > OK. This means that whatever I/O workload we've done has caused the NVME > card to stop responding for 30s, so we reset it. > > I figured as much ;-) > > > So it's an intel card. > > Yes - I already added this info several times. 6 of them, 2.5“ NVME „disk > drives“. > Yea, it was more of a knowing sigh... > OK. That suggests Intel has a problem with their firmware. > > I came across this one: > https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=211713 > > Is it more probable that Intel has got buggy firmware here than that > „we“ are missing interrupts? > More probable bad firmware. One of the things I think that is in HEAD is a mitigation for this that looks for completed IO on timeout before doing a reset. The mainboard is the Supermicro H11SSW-NT. Two NVME drive bays share > a connector on the mainboard: > > NVMe Ports ( NVMe 0~7, 10, 11, 14, 15) > > The H11SSW-iN/NT has tweleve (12) NVMe ports (2 ports per 1 Slim > SAS connector) on the motherboard. > These ports provide high-speed, low-latency PCI-E 3.0 x4 > connections directly from the CPU to NVMe Solid > State (SSD) drives. This greatly increases SSD data- throughput > performance and significantly reduces PCI-E > latency by simplifying driver/software requirements resulting from > direct PCI-E interface from the CPU to the NVMe SSD drives. > > Is this purely mechanical or do two drives share PCI-E resources? Which > would explain > why the problems always come in pairs (nvme6 and nvme7, for example). > I'm unfamiliar with this setup, but coming in pairs increases the missed interrupt theory in my mind. Firmware issues usually don't come in pairs. This afternoon I set up a system with 4 drives and I was not able to > reproduce the problem. > (We just got 3 more machines which happened to have 4 drives each and no > M.2 directly > on the mainboard). > I will change the config to 6 drives like with the two FreeNAS systems in > our data center. > > > [… nda(4) ...] > > I doubt that would have any effect. They both throw as much I/O onto the > card as possible in the default config. > > I found out - yes, just the same. > NDA drives with an iosched kernel will be able to rate limit, which may be useful as a diagnostic tool... > There's been some minor improvements in -current here. Any chance you > could experimentally try that with this test? You won't get as many I/O > abort errors (since we don't print those), and we have a few more > workarounds for the reset path (though honestly, it's still kinda stinky). > > HEAD or RELENG_12, too? > HEAD is preferred, but any recent snapshot will do. Warner Kind regards, > Patrick > -- > punkt.de GmbH Internet - Dienstleistungen - Beratung > Kaiserallee 13a Tel.: 0721 9109-0 Fax: -100 > 76133 Karlsruhe i...@punkt.de http://punkt.de > AG Mannheim 108285 Gf: Juergen Egeling > > _______________________________________________ freebsd-stable@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
