Hi everybody, Does anyone have an idea on this?
Thank you in advance! With best regards, Tom. -- ________________________________________________________________________ | [email protected] | | Tom Ghyselinck | Senior Engineer | Excentis N.V. | Gildestraat 8 B-9000 Ghent, Belgium | Tel: +32 9 269 22 91 - Fax: +32 9 329 31 74 ________________________________________________________________________ On wo, 2015-04-15 at 14:18 +0200, Tom Ghyselinck wrote: > > Hi, > > We are developing a traffic generator/analyser using PF_RING ZC on Intel > X710 Dual-port 10Gbps NICs. > > We got stuck at an issue where packets at receive side have unwanted > buffering before they are received by our application. > > - Our application uses the two interfaces. > - For each interface we open two PF_RING rings, one in send-only mode > and one in receive-only mode. > - It is a linux-based system. > - Our receive threads have scheduling policy `SCHED_RR` with minimum > priority. > - Our transmission threads have scheduling policy `SCHED_FIFO` with > minimum priority. > > For testing we connected our interfaces back-to-back > In one of the scenarios we noticed: > - We see the `pfring_poll()` method return with timeout at the correct > timeout interval we specified (for both interfaces). > - We transmit a packet at interface A > - `pfring_poll()`/`pfring_recv()` at interface B does not detect it. > - When we check the interace statistics (ethtool -S enp8s0f1), the 'rx' > counters at interface B *did increase*. > - It is only after 8 packets (approx. 8 seconds) that we receive those 8 > packets at once. > > I have tried: > - Different pf_ring kernel module options (quick_mode) > - A lot of device configurations/features enabled / disabled. > - Many flags for `pfring_open` (currently PF_RING_PROMISC | > PF_RING_DO_NOT_PARSE | PF_RING_TIMESTAMP | PF_RING_HW_TIMESTAMP | > PF_RING_DNA_FIXED_RSS_Q_0 | PF_RING_REENTRANT) > > Can someone help us out? > Does anyone have any idea how to disable this caching or decrease the > timeout when the packets are released to the application? > > Thank you very much in advance! > > P.S. Our current device configuration is: > > # ethtool -l enp8s0f0 > Channel parameters for enp8s0f0: > Pre-set maximums: > RX: 0 > TX: 0 > Other: 1 > Combined: 64 > Current hardware settings: > RX: 0 > TX: 0 > Other: 1 > Combined: 1 > > # ethtool -k enp8s0f0 > Features for enp8s0f0: > rx-checksumming: on > tx-checksumming: on > tx-checksum-ipv4: on > tx-checksum-ip-generic: off [fixed] > tx-checksum-ipv6: on > tx-checksum-fcoe-crc: off [fixed] > tx-checksum-sctp: on > scatter-gather: on > tx-scatter-gather: on > tx-scatter-gather-fraglist: off [fixed] > tcp-segmentation-offload: off > tx-tcp-segmentation: off > tx-tcp-ecn-segmentation: off > tx-tcp6-segmentation: off > udp-fragmentation-offload: off [fixed] > generic-segmentation-offload: off > generic-receive-offload: on > large-receive-offload: off [fixed] > rx-vlan-offload: off > tx-vlan-offload: off > ntuple-filters: on > receive-hashing: on > highdma: on > rx-vlan-filter: on > vlan-challenged: off [fixed] > tx-lockless: off [fixed] > netns-local: off [fixed] > tx-gso-robust: off [fixed] > tx-fcoe-segmentation: off [fixed] > fcoe-mtu: off [fixed] > tx-nocache-copy: on > loopback: off [fixed] > rx-fcs: off [fixed] > rx-all: off [fixed] > > # ethtool -g enp8s0f0 > Ring parameters for enp8s0f0: > Pre-set maximums: > RX: 4096 > RX Mini: 0 > RX Jumbo: 0 > TX: 4096 > Current hardware settings: > RX: 512 > RX Mini: 0 > RX Jumbo: 0 > TX: 512 > > # ethtool -c enp8s0f0 > Coalesce parameters for enp8s0f0: > Adaptive RX: on TX: on > stats-block-usecs: 0 > sample-interval: 0 > pkt-rate-low: 0 > pkt-rate-high: 0 > > rx-usecs: 62 > rx-frames: 0 > rx-usecs-irq: 0 > rx-frames-irq: 256 > > tx-usecs: 122 > tx-frames: 0 > tx-usecs-irq: 0 > tx-frames-irq: 256 > > rx-usecs-low: 0 > rx-frame-low: 0 > tx-usecs-low: 0 > tx-frame-low: 0 > > rx-usecs-high: 0 > rx-frame-high: 0 > tx-usecs-high: 0 > tx-frame-high: 0 > > With best regards, > Tom. > > _______________________________________________ Ntop mailing list [email protected] http://listgateway.unipi.it/mailman/listinfo/ntop
