lukego

Interested in opportunities in computer networking? Check out Snabb Switch!

Snabb Switch is open source software for solving novel problems in networking. We are blending the latest techniques for high-performance x86 packet processing together with a high-level LuaJIT programming interface. Our goal is to offer the easiest way to create and deploy new network functions in large scale networks.

With Snabb Switch you can:

1. Use 10G network interfaces at full speed right out of the box.
2. Create your own new functionality with LuaJIT scripts.
3. Join a community of creative networking professionals who all want your project to succeed.
4. Use the Snabb Lab to test your code with 500+ Gbps of networking bandwidth in Xeon servers with 1G/10G/40G adapters from Intel, Mellanox, SolarFlare, and Chelsio.

lukego

Simple JIT compiler to create a fixed-size page translation cache. Generates simple linear search code without branches. On small tables it costs about 16 cycles including the overhead of looping and calling from Lua.

Cache table layout:

struct tlb_entry { int64_t page, offset; }

JIT compiler source:

lukego

Exerpt from `perf top`:

```
 25.29%  perf-26553.map      [.] TRACE_7::lib/virtio/net_device.lua:161
 22.10%  perf-26553.map      [.] TRACE_19::lib/virtio/net_device.lua:236
  7.63%  perf-26553.map      [.] TRACE_15::apps/intel/intel_app.lua:77
  6.37%  snabb               [.] lj_alloc_free
  6.22%  snabb               [.] release_unused_segments
  4.73%  perf-26553.map      [.] TRACE_14::apps/intel/intel_app.lua:92
  3.93%  snabb               [.] packet_reset

lukego

link report
9,993,377       sent on vm.tx -> nic.rx (loss rate: 0%)
10,000,116      sent on nic.tx -> vm.rx (loss rate: 0%)

Processed 10.0 million packets in 3.93 seconds
Made 184,436 breaths: 54.22 packets per breath; 21.28us per breath
Rate(Mpps):     2.548
98%  Compiled
  -- 24%  tlb.lua:lookup
  -- 12%  net_device.lua:vm_buffer  

lukego

luke@grindelwald:~/hacking/snabbswitch/src$ for i in $(seq 1 10); do make && sudo SNABB=$(pwd)/snabb NFV_PACKETS=10e6 scripts/bench_env/loadgen-snabb-nic-guest.sh; done | grep Mpps
Rate(Mpps):     4.804
Rate(Mpps):     5.200
Rate(Mpps):     4.746
Rate(Mpps):     4.797
Rate(Mpps):     4.575
Rate(Mpps):     3.330
Rate(Mpps):     4.684
Rate(Mpps):     4.424
Rate(Mpps):     4.632

lukego

core/freelist.lua:14: freelist overflow
stack traceback:
        core/main.lua:137: in function <core/main.lua:135>
        [C]: in function 'assert'
        core/freelist.lua:14: in function 'add'
        lib/virtio/net_device.lua:182: in function 'get_transmit_buffers_from_vm'
        lib/virtio/net_device.lua:79: in function 'poll_vring_transmit'
        apps/vhost/vhost_user.lua:58: in function 'push'
        core/app.lua:189: in function 'breathe'
        core/app.lua:144: in function 'main'

lukego

diff --git a/src/apps/intel/intel10g.lua b/src/apps/intel/intel10g.lua
index 9882b96..ca2d0e0 100644
--- a/src/apps/intel/intel10g.lua
+++ b/src/apps/intel/intel10g.lua
@@ -277,7 +277,7 @@ end
 function set_SFI (dev)
    local autoc = dev.r.AUTOC()
    autoc = bor(
-      band(autoc, 0xFFFF0C7E),          -- clears FLU, 10g_pma, 1g_pma, restart_AN, LMS
+      band(autoc, 0xFFFF0C7F),          -- sets FLU; clears 10g_pma, 1g_pma, restart_AN, LMS

lukego

On 0000:01:00.0 got 3.652
On 0000:03:00.0 got 3.509
On 0000:05:00.0 got 3.688
On 0000:08:00.0 got 3.713
On 0000:82:00.0 got 3.682
On 0000:84:00.0 got 3.596
On 0000:86:00.0 got 3.759
On 0000:89:00.0 got 3.753
Rate(Mpps):     29.352

lukego

#!/usr/bin/env bash                                                                                                                   

# Mandatory Parameters:                                                                                                               
#   EVENTS_IN:  Directory to read incoming events                                                                                     
#   EVENTS_OUT: Directory to write accepted events                                                                                    
#                                                                                                                                     
# Optional Parameters:                                                                                                                
#   PROJECT:     Project name (regex fragment)                                                                                        
#   EVENTS_SKIP: Directory to write skipped events                            

lukego

# -*- mode: ruby -*-
# vi: set ft=ruby :

# Vagrantfile API/syntax version. Don't touch unless you know what you're doing!
VAGRANTFILE_API_VERSION = "2"

Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
  config.vm.box = "trusty"
  config.vm.provision "shell", path: "ci.sh"
  config.vm.provider "virtualbox" do |vb|