Obsługa 100M pps na platformie PC
Achieving very high speed of IP packet processing on commodity
PC platform using modern ...
Who are we?
Who are we? (1)
3
Przemysław Frasunek
• Multimedia and
Security Division
Director
• Responsible for
redCDN and
redGuardian...
4
Multimedia
Smart Grid
Cybersecurity
Phoenix-RTOS
Phoenix-PRIME
Hermes
Who are we? (2)
redCDN, WTF? (1)
• redCDN – the largest Polish CDN operated by Atende Software
• CDN nodes collocated in major Polish IXPs...
redCDN, WTF? (2)
6
redCDN, WTF? (3)
http://antyweb.pl/odwiedzilismy-atende-software-to-dzieki-nim-mozecie-ogladac-iple-i-player-pl/
100M pps…Wait ButWhy?
redGuardian – brief history – 2014 Q3
• The initial idea: hey, our CDN network is utilized mostly with outgoing traffic,
l...
redGuardian – brief history – 2014 Q4
• Let’s check the commodity hardware for ability to forward/filter large amounts
of ...
redGuardian – brief history – 2014 Q4 (test results)
11
redGuardian – brief history – 2014 Q4 (test results)
12
redGuardian – brief history – 2014 Q4
• Conclusion: generic OS-es with default network stacks are incapable of
handling mu...
redGuardian – brief history – 2014 Q4
14
redGuardian – brief history – 2014 Q4
• Step 3: simple DPDK-based L3 forwarder
– Based on example code in DPDK source tree...
redGuardian – brief history – 2015 Q1
• Step 5: ask Paweł for joining our team to lead development of our
own DDoS-mitigat...
100M pps… what is the problem?
Challenge 100Mpps – explained
PHY speed 60B* frames [pps] 1514B frames [pps]
1Gbps ~1.48M** (1 488 095) ~81k (81274)
10Gbp...
Challenge 100Mpps – CPU cycles, budget estimation
For 10Gbps we have:
• 1277 ns per full-sized frame
• 67.2ns per small fr...
So what is the problem?
• OS network stacks were not designed with these speeds in mind, they
were designed as control pla...
Hardware – is it capable?
Crucial components:
1. Network Interfaces
2. PCIe bus
3. memory
4. CPU
21
PCIe bus vs. NIC vs. memory
Interface Raw unidirectional speed Notes
Eth 10Gbps ~ 1250MB/s
Eth 2x10Gbps ~ 2500MB/s typical...
NICs – speeds and vendors
• 10 Gbps – mature, too slow 
• 25Gbps – gaining popularity (http://www.2550100.com/, http://25...
NICs – multiqueue and other features
• multiqueue
– e.g. 128 RX+TX pairs
– RX distribution by RSS or manual
– RSS hashing ...
NICs – examples
25
i40e
ixgbe
Modern Xeon CPUs – example
Architecture: x86_64
On-line CPU(s) list: 0-31
Thread(s) per core: 2
Core(s) per socket: 16
Mod...
Modern Xeon 1-2 socket CPUs
source: https://en.wikipedia.org/wiki/List_of_Intel_Xeon_microprocessors
27
• V3: Haswell fami...
AdvancedVector Extensions (AVX)
• With AVX2, we have 256-bit registers and
instructions
• Thanks to that one can calculate...
AdvancedVector Extensions (AVX) – example
static inline void clear_dropped_verdicts(uint32_t *vp, size_t n)
{
#ifdef __AVX...
Intel Data Direct I/O (DDIO)
# cpuid | grep 'direct cache access' | head -1
direct cache access = true
30
source: Intel® D...
Intel Cache AllocationTechnology (CAT)
31
sources:
https://github.com/01org/intel-cmt-cat
http://danluu.com/intel-cat/
All...
Crazy idea
• So HW is capable, OS is not
• NICs use DMA and we already have Userspace I/O
• Let’s bypass OS network stack ...
Dataplane frameworks*
DPDK Netmap PF RING ZC Snabb Switch
OS Linux, FreeBSD FreeBSD, Linux Linux Linux
license BSD BSD LGP...
DPDK simplified overview (1)
• DPDK comes as a complete set
of modules
• everything runs around EAL
• physical NICs access...
DPDK simplified overview (2) – components
RTE part Description What for?
ACL access-lists packet matching
LPM DIR-24-8 rou...
What can we build with these tools?
• switch
• router
• stateless and stateful firewall
• IDS/IPS
• load balancer
• userla...
Some insights
How to code?
• packet batching
• vectorization (AVX)
• memory preallocation and
hugepages
• memory channel awareness
• dat...
Multiple cores scaling vs. traffic policing and counters
39
• remove shared variables, get rid of
locking
• maintain separ...
Automated regression tests are a must
• performance
• features
• local (pcap) and real NICs
• different drivers
40
$ make ...
Packet crafting with Scapy
>>> p=Ether()/IP()/ICMP()
>>> p.show()
###[ Ethernet ]###
dst= ff:ff:ff:ff:ff:ff
src= 00:00:00:...
Performance testing – granularity (1)
42
• RX performance snapshots,
1ms resolution
• average performance
seems OK
• what ...
Performance testing – granularity (2)
• very nice
• but WTF?
• thermal interactions
• modern CPUs scale their
clock and it...
Profiling
• Workload is repeatable
• Sampling profilers are great for finding hot spots
• Simple changes can have huge per...
Summary
• PC may be faster than you think
• In-depth understading is required to develop fast, working
solutions
• Commerc...
Thank you for your attention!
BTW, we are hiring!
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100 M pps on PC.

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Presentation regarding redGuardian Anti DDoS system and DPDK dataplane programming, shown at PLNOG conference.

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100 M pps on PC.

  1. 1. Obsługa 100M pps na platformie PC Achieving very high speed of IP packet processing on commodity PC platform using modern kernel bypassing techniques version 2016.02.29a
  2. 2. Who are we?
  3. 3. Who are we? (1) 3 Przemysław Frasunek • Multimedia and Security Division Director • Responsible for redCDN and redGuardian services • IT security passionate – over 40 vulnerabilities reported on BUGTRAQ since 1999 Paweł Małachowski • Leads redGuardian development team • ISP/telco/UNIX background since 1996 • Experience as business analyst, system engineer, IT operations manager
  4. 4. 4 Multimedia Smart Grid Cybersecurity Phoenix-RTOS Phoenix-PRIME Hermes Who are we? (2)
  5. 5. redCDN, WTF? (1) • redCDN – the largest Polish CDN operated by Atende Software • CDN nodes collocated in major Polish IXPs and ISPs • Over 400 Gbps of network capacity • Fully based on in-house developed software since 2006 • Supports most important multimedia protocols (Smooth Streaming, MPEG-DASH, HLS) and simple HTTP/HTTPS 5
  6. 6. redCDN, WTF? (2) 6
  7. 7. redCDN, WTF? (3) http://antyweb.pl/odwiedzilismy-atende-software-to-dzieki-nim-mozecie-ogladac-iple-i-player-pl/
  8. 8. 100M pps…Wait ButWhy?
  9. 9. redGuardian – brief history – 2014 Q3 • The initial idea: hey, our CDN network is utilized mostly with outgoing traffic, let’s do something new to utilize it with incoming traffic • Maybe a DDoS protection service offered in a scrubbing center model? • Let’s test DDoS-mitigation appliances available on the market • Conclusions: – Radware, Huawei: too expensive, not suited for multitenancy – Arbor: they didn’t allowed us to test their solution 9
  10. 10. redGuardian – brief history – 2014 Q4 • Let’s check the commodity hardware for ability to forward/filter large amounts of traffic • Our goal: at least 20 Gbit/s (29.6Mpps @ 64B packets) on a single Intel-based server • Step 1:Vanilla Linux – Intel Xeon E3-1200 (single-socket, quad-core, non-hyperthreaded) – 2x Intel 10 GbE NIC based on Intel's X540-AT2 Ethernet controller – 16 GB RAM (4x4 GB DDR3 1.3GHz) – Ubuntu 14.4.1 LTS for x86-64 architecture (kernel 3.13.0-40-generic) 10
  11. 11. redGuardian – brief history – 2014 Q4 (test results) 11
  12. 12. redGuardian – brief history – 2014 Q4 (test results) 12
  13. 13. redGuardian – brief history – 2014 Q4 • Conclusion: generic OS-es with default network stacks are incapable of handling multiple 10 GbE interfaces saturated with smallest frames • Step 2: evaluation of data-plane architectures – Intel DPDK (http://dpdk.org) – A set of libraries for fast packet processing (BSD license) – Handles packets within minimum number of CPU cycles – …but provides only very basic set of functions (memory management, ring buffers, poll-mode drivers) – Almost all of IP stack needs to be implemented on your own 13
  14. 14. redGuardian – brief history – 2014 Q4 14
  15. 15. redGuardian – brief history – 2014 Q4 • Step 3: simple DPDK-based L3 forwarder – Based on example code in DPDK source tree – No ARP, single next-hop, no ACLs – 3 CPU cores isolated from the Linux scheduler and IRQ balancer and dedicated to DPDK – Simultaneous RX andTX of 14.8M pps @ 64B – Hell yeah! • Step 4: simple forwarder with ACLs – Simple L3 ACLs (IP/mask) – 100k random entries – 10GbE wire speed on a single CPU core 15
  16. 16. redGuardian – brief history – 2015 Q1 • Step 5: ask Paweł for joining our team to lead development of our own DDoS-mitigation solution  – In first phase, we decided to focus on mitigation of volumetric attacks (especially DNS and NTP reflection) – In next phases, we would like to inspect and inject traffic into HTTP sessions – We needed to implement a filter module and web panel – We wanted to handle over 100 Gbps on a single PC – Our filtering nodes should be installed in all major CDN sites – Hardcore development started on March 2015 16
  17. 17. 100M pps… what is the problem?
  18. 18. Challenge 100Mpps – explained PHY speed 60B* frames [pps] 1514B frames [pps] 1Gbps ~1.48M** (1 488 095) ~81k (81274) 10Gbps ~14.88M (14 880 952) ~812k (812743) 40Gbps ~59.52M ~3.25M 100Gbps ~148.8M ~8.127M 18 So 100M pps FDX requires 7x10Gbps ports… easy! * 3B gap, 8B preamble, 60B payload, 4B CRC, no 802.1Q tag ** 1.86M with some cheating
  19. 19. Challenge 100Mpps – CPU cycles, budget estimation For 10Gbps we have: • 1277 ns per full-sized frame • 67.2ns per small frame, this can be estimated as 200 cycles/frame on modern 3GHz CPU For 40Gbps: 16,8 ns. For 100Gbps: 6,7 ns. 19 Operation Time cost* register <1ns (~1 cycle) L1 cache ~1 ns (~3 cycles) L2 cache ~4 ns L3 cache ~8-12 ns atomic lock+unlock 16 ns cache miss / RAM access ~32-65 ns syscall (beware of SELinux) 50–100 ns sources: • „Network stack challenges at increasing speeds. The 100Gbit/s challenge”, RedHat 2015 • „HOW TO TEST 10 GIGABIT ETHERNET PERFORMANCE”, Spirent Whitepaper, 2012 • „The 7 Deadly Sins... of Packet Processing” from DPDK Summit Userspace, Oct 2015 • http://mechanical-sympathy.blogspot.co.uk/2013/02/cpu-cache-flushing-fallacy.html * Note, these costs may vary between different CPU types, memories etc.
  20. 20. So what is the problem? • OS network stacks were not designed with these speeds in mind, they were designed as control planes, not data planes. • We have many CPU cores these days, but some OS-es network stacks does not scale. 20 sources: • http://people.netfilter.org/hawk/presentations/LCA2015/net_stack_challenges_100G_LCA2015.pdf • „Shmoocon 2013 - C10M Defending The Internet At Scale”: https://www.youtube.com/watch?v=73XNtI0w7jA • http://highscalability.com/blog/2013/5/13/the-secret-to-10-million-concurrent-connections-the-kernel-i.html
  21. 21. Hardware – is it capable? Crucial components: 1. Network Interfaces 2. PCIe bus 3. memory 4. CPU 21
  22. 22. PCIe bus vs. NIC vs. memory Interface Raw unidirectional speed Notes Eth 10Gbps ~ 1250MB/s Eth 2x10Gbps ~ 2500MB/s typically PCIe 2.0, 8x; but some NICs give ~80% speed with 64 frames FDX on both ports Eth 40Gbps ~ 5000MB/s PCIe 2.0 8x, 5GT/s ~ 4000 MB/s transport, ACK/transaction overhead; 8b/10b PCIe 3.0, 4x ~ 3940 MB/s 128b/130b PCIe 3.0, 8x, 8GT/s <8000 MB/s PCIe 3.0, 16x, 8GT/s ~ 15754 MB/s DDR3-1866, ~1,866GT/s ~ 14933 MB/s PC3-14900 22
  23. 23. NICs – speeds and vendors • 10 Gbps – mature, too slow  • 25Gbps – gaining popularity (http://www.2550100.com/, http://25gethernet.org/) • 40Gbps – too much • 2x40Gbps – cheating • 100Gbps, 2x100Gbs – available! PCIe can be splitted • ensure port speeds matches PCIe bus width + overhead! • some cards have internal limits • some motherboards share bus lanes between slots Some of the vendors: • Chelsio, Emulex, Intel, Mellanox, QLogic, Solarflare… • FPGA-based:AccoladeTechnology, Invea-Tech, Liberouter COMBO, Myricom, Napatech, … 23
  24. 24. NICs – multiqueue and other features • multiqueue – e.g. 128 RX+TX pairs – RX distribution by RSS or manual – RSS hashing L3/L4 (ECMP like) – Flow Director rules can be set with ethtool • performance drop • offloads:VLAN, checksum, encapsulation, etc. • DCB andVM/VF features • SR-IOV • scatter & gather • FPGA on board • black magic 24 source: http://dpdk.org/doc/
  25. 25. NICs – examples 25 i40e ixgbe
  26. 26. Modern Xeon CPUs – example Architecture: x86_64 On-line CPU(s) list: 0-31 Thread(s) per core: 2 Core(s) per socket: 16 Model name: Intel(R) Xeon(R) CPU E5-2698 v3 @ 2.30GHz CPU MHz: 1201.210 CPU max MHz: 3600.0000 CPU min MHz: 1200.0000 BogoMIPS: 4599.81 Virtualization: VT-x L1d cache: 32K L1i cache: 32K L2 cache: 256K L3 cache: 40960K NUMA node0 CPU(s): 0-31 microarchitectures: Skylake (new, 2015Q4, E3 only for now), Broadwell (quite new), Haswell (this one) 26
  27. 27. Modern Xeon 1-2 socket CPUs source: https://en.wikipedia.org/wiki/List_of_Intel_Xeon_microprocessors 27 • V3: Haswell family • V4: Broadwell family • No Skylake E5s yet • AVX2: a must! • AVX512: maybe in 2017… • DDIO: recommended • CAT: interesting! • NUMA: avoid QPI overhead
  28. 28. AdvancedVector Extensions (AVX) • With AVX2, we have 256-bit registers and instructions • Thanks to that one can calculate multiple operations „at once” (SIMD) 28 sources: https://en.wikipedia.org/wiki/Advanced_Vector_Extensions https://software.intel.com/en-us/node/513925 Intrinsics for Arithmetic Operations Intrinsics for Arithmetic Shift Operations Intrinsics for Blend Operations Intrinsics for Bitwise Operations Intrinsics for Broadcast Operations Intrinsics for Compare Operations Intrinsics for Fused Multiply Add Operations Intrinsics for GATHER Operations Intrinsics for Logical Shift Operations Intrinsics for Insert/Extract Operations Intrinsics for Masked Load/Store Operations Intrinsics for Miscellaneous Operations Intrinsics for Operations to Manipulate Integer Data at Bit-Granularity Intrinsics for Pack/Unpack Operations Intrinsics for Packed Move with Extend Operations Intrinsics for Permute Operations Intrinsics for Shuffle Operations Intrinsics for Intel® Transactional Synchronization Extensions (Intel® TSX)
  29. 29. AdvancedVector Extensions (AVX) – example static inline void clear_dropped_verdicts(uint32_t *vp, size_t n) { #ifdef __AVX2__ static_assert(ACL_USERDATA_DROP == (1u << 31), "AVX2 code assumes ACL_USERDATA_DROP == 2^31"); for (;;) { __m256i dropmask = _mm256_loadu_si256((__m256i *)vp); _mm256_maskstore_epi32((int *)vp, dropmask, _mm256_setzero_si256()); if (n <= 8) break; n -= 8; vp += 8; } #else for (size_t i = 0; i < n; ++i) if (vp[i] & ACL_USERDATA_DROP) vp[i] = 0; #endif } code: redGuardian dataplane explanation source: https://software.intel.com/en-us/node/513925 29 Loads integer values from the 256-bit unaligned memory location pointed to by *a, into a destination integer vector, which is returned by the intrinsic. Conditionally stores 32-bit data elements from the source vector into the corresponding elements of the vector in memory referenced by addr. If an element of mask is 0, corresponding element of the result vector in memory stays unchanged. Only the most significant bit of each element in the vector mask is used. Sets all the elements of an integer vector to zero and returns the integer vector.
  30. 30. Intel Data Direct I/O (DDIO) # cpuid | grep 'direct cache access' | head -1 direct cache access = true 30 source: Intel® Data Direct I/O Technology (Intel® DDIO): A Primer / Technical Brief NIC pushes data directly into CPU L3 cache. Thus, in some usecases, there are no memory lookups at all. Very cool! Poor man’s TCAM?
  31. 31. Intel Cache AllocationTechnology (CAT) 31 sources: https://github.com/01org/intel-cmt-cat http://danluu.com/intel-cat/ Allows CPU L3 cache partitioning. But why? • Cache eviction problem • Low priority tasks won’t trash cache for high priority tasks, e.g. control plane vs. data plane on the same CPU socket • Useful also in virtualized environments (e.g. someVMs need low latencies) Supported on: E5-2658 v3, E5-2648L v3, E5-2628L v3, E5-2618L v3, E5-2608L v3 and E5-2658A v3, E3-1258L v4 and E3-1278L v4
  32. 32. Crazy idea • So HW is capable, OS is not • NICs use DMA and we already have Userspace I/O • Let’s bypass OS network stack and work with NICs directly! 32 source: 123rf.com
  33. 33. Dataplane frameworks* DPDK Netmap PF RING ZC Snabb Switch OS Linux, FreeBSD FreeBSD, Linux Linux Linux license BSD BSD LGPL 2.1 + paid ZC driver Apache 2.0 language C C C LuaJIT bifurcated driver - + + - support & community Intel, 6Wind and some Well Known Vendors FreeBSD, EU funding ntop Snabb Co. sample usecase appliances, NFV NFV, routing acceleration packet interception IDS/IPS NFV notes extremely optimized huge library of components WIP: ARM, Power8 support available OOTB, ongoing pfSense integration simple examples included, opensource IDS drivers less mature, innovative, DSL, Lua GC 33 * skipped: PacketShader I/O Engine, PFQ, ef_vi, OpenDataPlane API
  34. 34. DPDK simplified overview (1) • DPDK comes as a complete set of modules • everything runs around EAL • physical NICs accessed via Poll Mode Drivers (requires UIO) – Some PMDs are not mature enough • VM drivers are available as well • packets are exchanged via rings • libraries for hashing, route lookups,ACLs, QoS, encryption etc. provided 34 source: http://dpdk.readthedocs.org/en/latest/prog_guide
  35. 35. DPDK simplified overview (2) – components RTE part Description What for? ACL access-lists packet matching LPM DIR-24-8 routing lookups *hash calculate hashes based on packet headers state, ARP, flow lookups, etc. crypto crypto devices IPsec VPNs acceleration ring circular packet buffers HW/SW packet exchange QoS metering, scheduling, RED QoS packet framework pipelines, table lookups complex packet flow, OpenFlow- like … memory, locking, power, timing, etc. 35
  36. 36. What can we build with these tools? • switch • router • stateless and stateful firewall • IDS/IPS • load balancer • userland UDP stack • userlandTCP stack • traffic recorder • fast internet scanners • stateless packet generator • stateful, application-like flow generator • IPsecVPN gateway • tunnel broker • accelerated key-value DB • accelerated NAS (and there is also SPDK) • … 36
  37. 37. Some insights
  38. 38. How to code? • packet batching • vectorization (AVX) • memory preallocation and hugepages • memory channel awareness • data prefetching • cache-friendly data structures, cache aligning • no data copying • no syscalls • no locking, almost no atomics, compare and swap etc. 38 • polling (but not too often), no interrupts • one thread per core • branch prediction hints • function inlining • NUMA locality • time measure – RDTSC is not for free some of the sources: • http://dpdk.readthedocs.org/en/latest/prog_guide/writing_efficient_code.html • https://dpdksummit.com/Archive/pdf/DPDK-Dublin2015- SevenDeadlySinsPacketProcessing.pdf • http://www.net.in.tum.de/fileadmin/bibtex/publications/theses/2014-gallenmueller- high-speed-packet-processing.pdf • https://lwn.net/Articles/629155/
  39. 39. Multiple cores scaling vs. traffic policing and counters 39 • remove shared variables, get rid of locking • maintain separate dataset per core • test with all cores available • how to synchronize ratelimiters and borrow bandwidth between cores?
  40. 40. Automated regression tests are a must • performance • features • local (pcap) and real NICs • different drivers 40 $ make run-tests [...] ACL with drop rule: drops ... #03 passed ACL with no rules (empty): drops ... #04 passed [...] Not supported protocols are dropped ... #19 passed Packets with TTL<=1 are dropped ... #20 passed [...] MTU-sized IP packets are forwarded ... #25 passed IP len > reported frame len: dropped ... #26 passed IP len < reported frame len: truncated ... #27 passed [...] ----------------------------------- Perf tests on ixgbe: ----------------------------------- acl_limit RX/TX: 7139 / 9995 (min_rx 7134; max_rx 7143; dev_rx 2.5; dev_tx 1.8) acl_pass RX/TX: 7149 / 9996 (min_rx 6086; max_rx 7326; dev_rx 367.5; dev_tx 1.1) trivial RX/TX: 7862 / 10000 (min_rx 7658; max_rx 7903; dev_rx 68.3; dev_tx 0.7) long_acl RX/TX: 5502 / 9996 (min_rx 5498; max_rx 5506; dev_rx 2.0; dev_tx 0.3) -----------------------------------
  41. 41. Packet crafting with Scapy >>> p=Ether()/IP()/ICMP() >>> p.show() ###[ Ethernet ]### dst= ff:ff:ff:ff:ff:ff src= 00:00:00:00:00:00 type= 0x800 ###[ IP ]### version= 4 ihl= None tos= 0x0 len= None id= 1 flags= frag= 0 ttl= 64 proto= icmp chksum= None src= 127.0.0.1 dst= 127.0.0.1 options ###[ ICMP ]### type= echo-request code= 0 chksum= None id= 0x0 seq= 0x0 41 def test_tcp_flags(self): # pass syn,!ack pkt1 = evalP(RAND_ETH / IP(src="1.2.3.4", dst="10.0.2.1") / TCP(sport=1, dport=2222, flags='S')) pkt2 = evalP(RAND_ETH / IP(src="1.2.3.4", dst="10.0.2.1") / TCP(sport=1, dport=2222, flags='SA')) pkt3 = evalP(RAND_ETH / IP(src="1.2.3.4", dst="10.0.2.1") / TCP(sport=1, dport=2222, flags='A')) pkt4 = evalP(RAND_ETH / IP(src="1.2.3.4", dst="10.0.2.1") / TCP(sport=1, dport=2222, flags='SU')) pkt5 = evalP(RAND_ETH / IP(src="1.2.3.4", dst="10.0.2.1") / TCP(sport=1, dport=2222, flags='U')) # pass ns,!ack # NS flag is represented by least significant bit in reserved area pkt6 = evalP(RAND_ETH / IP(src="1.2.3.4", dst="10.0.2.1") / TCP(sport=1, dport=3333, flags='', reserved=1)) pkt7 = evalP(RAND_ETH / IP(src="1.2.3.4", dst="10.0.2.1") / TCP(sport=1, dport=3333, flags='A', reserved=1)) out = self.__test_forward(pkt1 + pkt2 + pkt3 + pkt4 + pkt5 + pkt6 + pkt7) pkt_eq_(pkt1 + pkt4 + pkt6, out) Gotcha! AssertionError: len(expected) != len(output) (9 != 8) first difference at 8: 'Ethernet/IP/TCP/Raw' != '<missing>'
  42. 42. Performance testing – granularity (1) 42 • RX performance snapshots, 1ms resolution • average performance seems OK • what if we look closer? • WTF? • isolate cores, avoid cache trashing
  43. 43. Performance testing – granularity (2) • very nice • but WTF? • thermal interactions • modern CPUs scale their clock and it is not always possible to control this 43
  44. 44. Profiling • Workload is repeatable • Sampling profilers are great for finding hot spots • Simple changes can have huge performance impact 44
  45. 45. Summary • PC may be faster than you think • In-depth understading is required to develop fast, working solutions • Commercial dataplane solutions are already here, virtual and physical • „Worse Is Better” 45
  46. 46. Thank you for your attention! BTW, we are hiring!

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