On 04/302014 Shirley Ma wrote: > On 04/30/2014 01:00 PM, Or Gerlitz wrote: > > On Wed, Apr 30, 2014 at 10:47 PM, Chuck Lever > > <chuck.le...@oracle.com> > > > >> If I understood Yan, he is trying to use NFS/RDMA in guests > >> (kvm?). We > >> are pretty sure that is not working at the moment, > > can you provide a short 1-2 liner why/what is broken there? the > > only > > thing which I can think of to be not-supported over mlx4 VFs is the > > proprietary FMRs, but AFAIK, the nfs-rdma code doesn't even have a > > mode which uses them, right? > I've created Xen guest on DomU. Dom0 PF works which has no mtts been > enabled, however DomU I hit this problem by just mounting the file > system: > mlx4_core 0000:00:04.0: Failed to allocate mtts for 66 pages(order 7) > mlx4_core 0000:00:04.0: Failed to allocate mtts for 4096 pages(order > 12) > mlx4_core 0000:00:04.0: Failed to allocate mtts for 4096 pages(order > 12) > > RDMA microbenchmark perftest works ok. I enabled mtts scripts when > booting the Xen guest. cat /proc/mtrr:
What OS/RDMA stack are you using? I'm not familiar with any mtts scripts, however I know there is an mtrr fixup script I wrote for the RDMA stack in Fedora/RHEL (and so I assume it's in Oracle Linux too, but I haven't checked). In fact, I assume that's the script you are referring to based on the fact that your next bit of your email cats the /proc/mtrr file. But I don't believe whether there is an mtrr setting mixup or not that is should have any impact on the mtts allocations in the driver. Even if your mtrr registers were set incorrectly, the problem then becomes either A) a serious performance bottleneck (in the case of Intel hardware that needs write combining in order to get more than about 50MByte/s of throughput on their cards) or B) failed operation because MMIO writes to the card are being cached/write combined when they should not be. I suspect this is more likely Xen related than mtts/mtrr related. > [root@ca-nfsdev1vm1 log]# cat /proc/mtrr > reg00: base=0x0f0000000 ( 3840MB), size= 128MB, count=1: uncachable > reg01: base=0x0f8000000 ( 3968MB), size= 64MB, count=1: uncachable > > lspci -v > 00:04.0 InfiniBand: Mellanox Technologies MT25400 Family [ConnectX-2 > Virtual Function] (rev b0) > Subsystem: Mellanox Technologies Device 61b0 > Physical Slot: 4 > Flags: bus master, fast devsel, latency 0 > Memory at f0000000 (64-bit, prefetchable) [size=128M] > Capabilities: [60] Express Endpoint, MSI 00 > Capabilities: [9c] MSI-X: Enable+ Count=4 Masked- > Kernel driver in use: mlx4_core > Kernel modules: mlx4_core > > I will need to find another machine to try KVM guest. Yan might hit a > different problem. > > I have ConnectX-2, FW level is 2.11.2012. Yan has ConnectX-3, he > tried > it on KVM guest. > >> but that is a priority > >> to get fixed. Shirley has a lab set up and has been looking into > >> it. > Shirley > -- > To unsubscribe from this list: send the line "unsubscribe linux-rdma" > in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Doug Ledford <dledf...@redhat.com> GPG KeyID: 0E572FDD http://people.redhat.com/dledford -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
