Computing Performance 2021
What’s On the Horizon
Brendan Gregg
YOW!

Disclaimers: About this talk
This is
a performance engineer's views about industry-wide server performance
This isn't
necessarily about my employer, or my employer’s views
an endorsement of any company/product or sponsored by anyone
professional market predictions (various companies sell such reports)
based on confidential materials
necessarily correct or fit for any purpose
My predictions may be wrong! They will be thought-provoking.
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Agenda
1. Processors
2. Memory
Slides are online and include extra details as fine print
Slides: http://www.brendangregg.com/Slides/YOW2021_ComputingPerformance.pdf
3. Disks
4. Networking
5. Runtimes
6. Kernels
7. Hypervisors
8. Observability
Not covering: Databases, file systems, front-end, mobile, desktop.
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

1. Processors
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Clock rate
Early Intel Processors
Processor
Intel 8086
Intel 386 DX
Intel Pentium
Pentium Pro
Pentium III
Intel Xeon
GHz
Max GHz
Year
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Clock rate
Server Processor Examples (AWS EC2)
Cores/T. Max GHz
4/8
8/16
10/20
24/48
24/48
Threads
Max GHz
Hardware Threads
Processor
Xeon X5550
Xeon E5-2665 0
Xeon E5-2680 v2
Platinum 8175M
Platinum 8259CL
Max GHz
Year
2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
Increase has leveled off due to power/efficiency
Workstation processors higher; E.g., 2020 Xeon W-1270P @ 5.1 GHz
Horizontal scaling instead
More CPU cores, hardware threads, and server instances
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Interconnects
Year
CPU Interconnect
2007 Intel FSB
2008 Intel QPI
2017 Intel UPI
Bandwidth
Gbytes/s
10 years:
6x core count
3.25x bus rate
Source: Systems Performance 2nd Edition
Figure 6.10 [Gregg 20]
Memory bus (covered later) also lagging
CPU utilization is wrong
Often mostly memory/interconnect stalls
90% CPU
...may mean:
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Lithography
Semiconductor Nanometer Process
32nm
TSMC expects volume production
of 3nm in 2022 [Quach 21a]
3nm
2nm
IBM has already built one [Quach 21b]
Source: Semiconductor device fabrication [Wikipedia 21a]
BTW: Silicon atom diameter ~0.2 nm [Wikipedia 21b]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)
Lithography limits expected to
be reached by 2029, switching
to stacked CPUs. [Moore 20]

Lithography
“Nanometer process”
since 2010 should be
considered a
marketing term
Semiconductor Nanometer Process
32nm
New terms proposed include:
GMT (gate pitch, metal pitch, tiers)
LMC (logic, memory, interconnects)
[Moore 20]
TSMC expects volume production
of 3nm in 2022 [Quach 21a]
3nm
2nm
Source: Semiconductor device fabrication [Wikipedia 21a]
BTW: Silicon atom diameter ~0.2 nm [Wikipedia 21b]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)
IBM has already built one [Quach 21b]
(it has 12nm gate length)
Lithography limits expected to
be reached by 2029, switching
to stacked CPUs. [Moore 20]

Other processor scaling
Special instructions
E.g., AVX-512 Vector Neural Network Instructions (VNNI)
Connected chiplets
Using embedded multi-die interconnect bridge (EMIB) [Alcorn 17]
3D stacking
E.g., Intel HBM, AMD Vcache [Cutress 21]
Hybrid core architecture
ARM big.LITTLE; Intel Alder Lake pcores/ecores [Alcorn 21]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Recent server processor examples
Vendor Processor
Clock
Cores/T.
2.3 - 3.4
40/80
AMD
Xeon Platinum “10nm”
8380 (Ice Lake)
EPYC 7713P “7nm”
2.0 - 3.675 64/128
Mar 2021
ARMbased
Ampere Altra
Q80-33
Dec 2020
Intel
Process
“7nm”
80/80
LLC
Date
Mbytes
Apr 2021
Intel Alder Lake for server (Sapphire Rapids) coming soon?
Other server processors: IBM Z, RISC-V
Coming soon to a datacenter near you
Although there is a TSMC chip shortage that may last through to 2022/2023 [Quatch 21][Ridley 21]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Cloud chip race
Amazon ARM/Graviton2
ARM Neoverse N1, 64 core, 2.5 GHz
Promising microbenchmark results in a test environment
Generic processors
x86
AMD
ARM
Grav2
MSFT
Microsoft ARM
ARM-based something coming soon [Warren 20]
Google SoC
Systems-on-Chip (SoC) coming soon [Vahdat 21]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)
GOOG
Cloud processors

Accelerators
GPUs
Parallel workloads, thousands of GPU cores. Widespread adoption in machine learning.
FPGAs
Reprogrammable semiconductors
Great potential, but needs specialists to program
Good for algorithms: compression, cryptocurrency,
video encoding, genomics, search, etc.
Microsoft FPGA-based configurable cloud [Russinovich 17]
Also IPUs, TPUs
Infrastructure processing units [Kummrow 21]
Tensor processing units [Google 21]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)
CPU
Ease of use
The “other” CPUs you
may not be monitoring
GPU
FPGA
Performance potential

Latest GPU examples
NVIDIA GeForce RTX 3090: 10,496 CUDA cores, 2020
[Burnes 20]
Cerebras Gen2 WSE: 850,000 AI-optimized cores, 2021
Use most of the silicon wafer for one chip.
2.6 trillion transistors, 23 kW. [Trader 21]
Previous version was already the “Largest chip ever built,”
and US$2M. [insideHPC 20]
GPU
SM: Streaming multiprocessor
SP: Streaming processor
Control
Control
Control
Control
Cores (SPs)
L2 Cache
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Latest FPGA examples
Xilinx Virtex UltraScale+ VU19P, 8,938,000 logic cells, 2019
Using 35B transistors. Also has 4.5 Tbit/s transceiver bandwidth (bidir), and 1.5 Tbit/sec DDR4 bandwidth
[Cutress 19]
Xilinx Virtex UltraScale+ VU9P, 2,586,000 logic cells, 2016
Deploy right now: AWS EC2 F1 instance type (up to 8 of these FPGAs per instance)
AMD is acquiring Xilinx
FPGA
BPF (covered later) already in FPGAs
E.g., 400 Gbit/s packet filter FFShark [Vega 20]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Predictions
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Multi-socket is doomed
Single socket is getting big enough (cores)
Already scaling horizontally (cloud)
One
socket
And in datacenters, via “blades” or “microservers”
Cloud
Why pay NUMA costs?
gt;100
cores
Two single-socket instances should out-perform one two-socket instance
1 hop
Mem
2 hops
CPU
CPU
Mem
Multi-socket future is mixed: one socket for cores, one GPU socket, one FPGA socket, etc. EMIB connected.
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: SMT future unclear
Simultaneous multithreading (SMT) == hardware threads
Performance variation
ARM cores competitive
Post meltdown/spectre
Some people turn them off
Possibilities:
SMT becomes “free”
Processor feature, not a cost basis
Turn “oh no! hardware threads” into
“great! bonus hardware threads!”
No more hardware threads
Future investment elsewhere
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Core count limits
Imagine an 850,000-core server processor in today’s systems...
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Core count limits
Worsening problems:
Memory-bound workloads
Kernel/app lock contention
False sharing
Power consumption
Core connectivity overheads
etc.
Source:
Figure 2.16
[Gregg 20]
General-purpose computing will hit a practical core limit
For a given memory subsystem & kernel, and running multiple applications
E.g., 1024 cores (except GPUs/ML/AI); Esperanto RISC-V is already reaching “kilocore” scale [Kostovic 21]
Apps themselves will hit an even smaller practical limit (some already have by design, e.g., Node.js and 2 CPUs)
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: pcores & ecores
Intel Alder Lake (desktop) has performance and efficiency cores
This will come to server
Server Processor
Efficiency core tasks:
Garbage collection
NUMA rebalancing
FS writeback compression & flushing
Backups
Security scanning
etc.
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)
pcore
pcore
pcore
pcore
ecores

My Prediction: 3 Eras of processor scaling
Delivered processor characteristics:
Era 1: Clock frequency
Era 2: Core/thread count
Era 3: Cache size & policy
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: 3 Eras of processor scaling
Practical server limits:
Era 1: Clock frequency
→ already reached by ~2005 (3.5 GHz)
Era 2: Core/thread count
→ limited by mid 2030s (e.g., 1024)
Era 3: Cache size & policy → limited by end of 2030s
Mid-century will need an entirely new computer hardware architecture, kernel memory architecture, or logic gate
technology, to progress further.
E.g., use of graphine, carbon nanotubes [Hruska 12]
This is after moving more to stacked processors
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: More processor vendors
ARM licensed or RISC-V
Including Apple M1 for servers
Era of CPU choice
Beware: “optimizing for the benchmark”
Don’t believe microbenchmarks without doing
“active benchmarking”: Root-cause perf analysis
while the benchmark is still running.
Intel back to innovating & competing
Pat Gelsinger now CEO
Cores
Benchmark Optimizer Unit
(confidential)
LLC
MMU
DogeCPU “+AggressiveOpts” processor
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Cloud CPU advantage
Large cloud vendors can analyze >gt;100,000 workloads directly
Via PMCs and other processor features.
Vast real-world detail to aid processor design
More detail than traditional processor vendors have, and detail available immediately whenever they want.
Will processor vendors offer their own clouds just to get the same data?
Machine-learning aided processor design
Based on the vast detail. Please point it at real-world workloads and not microbenchmarks.
Vast detail example: processor trace showing timestamped instructions:
# perf script --insn-trace --xed
date 31979 [003] 653971.670163672: ... (/lib/x86_64-linux-gnu/ld-2.27.so) mov %rsp, %rdi
date 31979 [003] 653971.670163672: ... (/lib/x86_64-linux-gnu/ld-2.27.so) callq 0x7f3bfbf4dea0
date 31979 [003] 653971.670163672: ... (/lib/x86_64-linux-gnu/ld-2.27.so) pushq %rbp
[...]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: FPGA turning point
Little adoption (outside cryptocurrency) until major app support
Solves the ease of use issue: Developers just configure the app (which may fetch and deploy an FMI)
BPF use cases are welcome, but still specialized/narrow
Needs runtime support, e.g., the JVM. Already work in this area (e.g., [TornadoVM 21]).
apt install openjdk-21
apt install openjdk-21-libfpga
JVM
FPGA
Accelerator
JVM
java -XX:+UseFPGA
(none of this is real, yet)
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

2. Memory
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Many workloads memory I/O bound
# ./pmcarch 1
K_CYCLES
K_INSTR
334937819 141680781
329721327 140928522
330388918 141393325
329889409 142876183
[...]
IPC BR_RETIRED
0.42 25744860335
0.43 25760806599
0.43 25821331202
0.43 26506966225
BR_MISPRED
BMR% LLCREF
2.08 1611987169
2.04 1504594986
1.88 1535130691
1.93 1501785676
LLCMISS
LLC%
# ./pmcarch 1
K_CYCLES
K_INSTR
[...]
IPC BR_RETIRED
0.66 4692322525
0.65 5286747667
0.70 4616980753
0.69 5055959631
BR_MISPRED
BMR% LLCREF
1.95 780435112
1.81 751335355
1.87 709841242
1.83 787333902
LLCMISS
LLC%
# ./pmcarch
K_CYCLES
K_INSTR
122697727 13892225
144881903 17918325
[...]
IPC BR_RETIRED
0.11 2604221808
0.12 3240599094
0.14 2722513072
0.15 2815805820
BR_MISPRED
BMR% LLCREF
1.56 419652590
1.48 489936685
1.56 401658252
1.48 386979370
LLCMISS
LLC%
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

DDR5 has better bandwidth
DDR5 has a faster bus
But not width
Needs processor support
E.g., Intel Alder Lake / Sapphire Rapids
512GB DDR5 DIMMs
Year
Memory
DDR-333
DDR2-800
DDR3-1600
DDR4-3200
DDR5-6400
Peak Bandwidth
Gbytes/s
Already released by Samsung [Shilov 21]
Desktop/Gamers already know about it:
Gbytes/s
2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

DDR latency
Year
Latency (ns)
Memory
DDR-333
Latency (ns)
DDR-333
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

DDR latency
Hasn’t changed in 20 years
This is single access latency
Same memory clock (200 MHz) [Greenberg 11]
Also see [Cutress 20][Goering 11]
Year
Low-latency DDR does exist
Reduced Latency DRAM (RLDRAM) by Infineon
and Micron: lower latency but lower density
Not seeing widespread server use (I’ve seen it
marketed towards HFT)
Latency (ns)
Memory
DDR-333
DDR2-800
DDR3-1600
DDR4-3200
DDR5-6400
Latency (ns)
DDR-333
DDR5-6400
:-(
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

HBM
High bandwidth memory, 3D stacking
Target uses cases include high performance computing, and virtual reality graphical processing [Macri 15]
GPUs already use it
Can be provided on-package
Intel Sapphire Rapids rumored to include 64 Gbyte HBM2E [Shilov 21d]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Server DRAM size
SuperMicro SuperServer B12SPE-CPU-25G
Single Socket (see earlier slides)
16 DIMM slots
4 TB DDR-4
Processor
socket
[SuperMicro 21]
Facebook Delta Lake (1S) OCP
6 DIMM slots
96 Gbytes DDR-4
Price/optimal for a typical WSS?
DIMMs
DIMMs
B12SPE-CPU-25G
[Haken 21]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Additional memory tier
3D XPoint (next section) memory mode:
- Can also operate in application direct mode and storage mode [Intel 21]
Main
memory
Persistent memory
Storage devices
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)
DRAM (

My Prediction: Extrapolation
Not a JEDEC announcement
Assumes miraculous
engineering work
For various challenges see [Peterson 20]
But will single-access latency
drop in DDR-6?
I’d guess not, DDR internals are already at
their cost-sweet-spot, leaving low-latency
for other memory technologies
Year
Memory
DDR-333
DDR2-800
DDR3-1600
DDR4-3200
DDR5-6400
DDR6-12800
DDR7-25600
DDR8-51200
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)
Peak Bandwidth
Gbytes/s
doubling

My Prediction: DDR5 “up to 2x” Wins
E.g., IPC 0.1 → ~0.2 for bandwidth-bound workloads
“good*”
>gt;2.0
Instruction bound
IPC
“bad”

My Prediction: HBM-only servers
Clouds offering “high bandwidth memory” HBM-only
instances
HBM on-processor
Finally helping memory catch up to core scaling
RLDRAM on-package as another option?
“Low latency memory” instance
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Extra tier too late
Competition isn’t disks, it’s Tbytes of DRAM
SuperMicro’s single socket should hit 8 Tbytes DDR-5
AWS EC2 p4.24xl has 1.1 Tbytes of DRAM (deploy now!)
How often does your working set size (WSS) not fit?
Across several of these for redundancy?
Next tier needs to get much bigger than DRAM (10+x)
and much cheaper to find an extra-tier use case
(e.g., cost based).
Meanwhile, DRAM is still getting bigger and faster
I developed the first cache tier between main memory
and disks to see widespread use:
the ZFS L2ARC [Gregg 08]
Main
memory
WSS
Persistent memory
Storage devices
“cold”
data

3. Disks
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Recent timeline for rotational disks
2005: Perpendicular magnetic recording (PMR)
Writes vertically using a shaped magnetic field for higher density
2013: Shingled magnetic recording (SMR)
(next slide)
2019: Multi-actuator technology (MAT)
Two sets of heads and actuators; like 2-drive RAID 0 [Alcorn 17].
2020: Energy-assisted magnetic recording (EAMR)
Western Digital 18TB & 20TB [Salter 20]
2021: Heat-assisted magnetic recording (HAMR)
Seagate 20TB HAMR drives [Shilov 21b]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Recent timeline for rotational disks
2005: Perpendicular magnetic recording (PMR)
Writes vertically using a shaped magnetic field for higher density
2013: Shingled magnetic recording (SMR)
(next slide)
2019: Multi-actuator technology (MAT)
Two sets of heads and actuators; like 2-drive RAID 0 [Alcorn 17].
2020: Energy-assisted magnetic recording (EAMR)
Western Digital 18TB & 20TB [Salter 20]
2021: Heat-assisted magnetic recording (HAMR)
Seagate 20TB HAMR drives [Shilov 21b]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)
I don’t know their perf characteristics yet 41

SMR
11-25% more storage, worse performance
Writes tracks in an overlapping way, like shingles on a roof. [Shimpi 13]
Overwritten data must be rewritten. Suited for archival (write once) workloads.
Read head
Written tracks
Look out for 18TB/20TB-with-SMR drive releases
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Flash memory-based disks
Single-Level Cell (SLC)
Multi-Level Cell (MLC)
Enterprise MLC (eMLC)
2009: Tri-Level Cell (TLC)
2009: Quad-Level Cell (QLC)
QLC is only rated for around 1,000 block-erase cycles [Liu 20].
2013: 3D NAND / Vertical NAND (V-NAND)
SK Hynix envisions 600-Layer 3D NAND [Shilov 21c]. Should be multi-Tbyte.
SSD performance pathologies: latency from aging, wear-leveling, fragmentation, internal compression, etc.
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Persistent memory-based disks
2017: 3D XPoint (Intel/Micron) Optane
Low and consistent latency (e.g., 14 us access latency) [Hady 18]
App-direct mode, memory mode, and as storage
Wordlines
Memory cells
Bitlines
Cell selection
3D XPoint
DRAM: Trapped electrons in a capacitor, requires refreshing
3D XPoint: Resistance change; layers of wordlines+cells+bitlines keep stacking vertically
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Latest storage device example
2021: Intel Optane memory H20
QLC 3D NAND storage (512 Gbytes / 1 Tbyte) +
3D XPoint as an accelerator (32 Gbytes)
Currently M.2 2280 form factor (laptops)
(Announced while I was developing these slides)
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Storage Interconnects
SAS-4 cards in development
(Storage attached SCSI)
PCIe 5.0 coming soon
(Peripheral Component Interconnect Express)
Intel already demoed on Sapphire Rapids [Hruska 20]
NVMe 1.4 latest
(Non-Volatile Memory Express)
Storage over PCIe bus
Support zoned namespace SSDs (ZNS) [ZonedStorage 21]
Bandwidth bounded by PCIe bus
These have features other than speed
Reliability, power management, virtualization support, etc.
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)
Year
Specified
202?
Interface
Year
Specified
Interface
SAS-1
SAS-2
SAS-3
SAS-4
SAS-5
PCIe 1
PCIe 2
PCIe 3
PCIe 4
PCIe 5
Bandwidth
Gbit/s
Bandwidth 16
lane Gbyte/s

Linux Kyber I/O scheduler
Multi-queue, target read & write latency
Up to 300x lower 99th percentile latencies [Gregg 18]
Linux 4.12 [Corbet 17]
reads (sync)
dispatch
writes (async)
Kyber (simplified)
dispatch
queue size adjust
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)
completions

My Prediction: Slower rotational
Archive focus
There’s ever-increasing demand for storage (incl. social video today; social VR tomorrow?)
Needed for archives
More “weird” pathologies. SMR is just the start.
Even less tolerant to shouting
Bigger, slower, and weirder
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: 3D XPoint
As a rotational disk accelerator
As petabyte storage
Layers keep stacking
3D NAND could get to petabytes too, but consumes more power
1 Pbyte = ~700M 3.5inch floppies!
And not really as a memory tier (DRAM too good) or widespread application direct (too much work when 3D
XPoint storage accelerators exist so apps can get benefits without changing anything)
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: More flash pathologies
Worse internal lifetime
More wear-leveling & logic
More latency outliers
Bigger, faster, and weirder
We need more observability of flash drive internals
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

4. Networking
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Latest Hardware
400 Gbit/s in use
E.g., 400 Gbit/s switches/routers by Cisco and Juniper, tranceivers by Arista and Intel
AWS EC2 P4 instance type (deploy now!)
On PCI, needs PCIe 5
800 Gbit/s next
[Charlene 20]
Terabit Ethernet (1 Tbit/s) not far away
More NIC features
E.g., inline kTLS (TLS offload to the NIC), e.g., Mellanox ConnectX-6-Dx [Gallatin 19]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Protocols
QUIC / HTTP/3
TCP-like sessions over (fast) UDP.
0-RTT connection handshakes. For clients that have previously communicated.
MP-TCP
Multipath TCP. Use multiple paths in parallel to improve throughput and reliability. RFC-8684 [Ford 20]
Linux support starting in 5.6.
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Linux TCP Congestion Control Algorithms
DCTCP
Data Center TCP. Linux 3.18. [Borkmann 14]
TCP NV
New Vegas. Linux 4.8
TCP BBR
Bottleneck Bandwidth and RTT (BBR) improves performance on packet loss networks [Cardwell 16]
With 1% packet loss, Netflix sees 3x better throughput [Gregg 18]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Linux Network Stack
Queues/
Tuning
Source: Systems Performance 2nd Edition, Figure 10.8 [Gregg 20]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Linux TCP send path
Keeps adding performance features
Source: Systems Performance 2nd Edition, Figure 10.11 [Gregg 20]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Software
eXpress Data Path (XDP) (uses eBPF)
Programmable fast lane for networking. In the Linux kernel.
A role previously served by DPDK and kernel bypass.
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: BPF in FPGAs/IPUs
Massive I/O tranceiver capabilities
Netronome already did BPF in hardware
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Cheap BPF routers
Linux + BPF + 400 GbE NIC
Cheap == commodity hardware
Use case from the beginning of eBPF (PLUMgrid)
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: More demand for network perf
Apps increasingly network
Netflix 4K content
Remote work & video conferencing
World of sensors
VR tourism
Facebook VR multiverse
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

5. Runtimes
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Latest Java
Sep 2018: Java 11 (LTS)
JEP 333 ZGC A Scalable Low-Latency Garbage Collector
JEP 331 Low-Overhead Heap Profiling
GC adaptive thread scaling
Sep 2021: Java 17 (LTS)
JEP 338: Vector API (JDK16)
Parallel GC improvements (JDK14)
Various other perf improvements (JDK12-17)
Java 11 includes JMH JDK microbenchmarks
[Redestad 19]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Predictions: Runtime features
FPGA as a compiler target
E.g., JVM c2 or Graal adding it as a compiler target, and becoming a compiler “killer” feature.
io_uring I/O libraries
Massively accelerate some I/O-bound workloads by switching libraries.
Adaptive runtime internals
I don’t want to pick between c2 and Graal. Let the runtime do both and pick fastest methods; ditto for testing
GC algorithms.
Not unlike the ZFS ARC shadow-testing different cache algorithms.
1000-core scalability support
Runtime/library/model support to help programmers write code to scale to hundreds of cores
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

6. Kernels
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Latest Kernels/OSes
Apr 2021: FreeBSD 13.0
Oct 2021: Linux 5.15 (LTS)
Nov 2021: Windows 10.0.22000.318
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Recent Linux perf features
2021: Syscall user dispatch (5.11)
2020: Static calls to improve Spectre-fix (5.10)
2020: BPF on socket lookups (5.9)
2020: Thermal pressure (5.7)
2020: MultiPath TCP (5.6)
2019: MADV_COLD, MADV_PAGEOUT (5.4)
2019: io_uring (5.1)
2019: UDP GRO (5.0)
2019: Multi-queue I/O default (5.0)
2018: TCP EDT (4.20)
2018: PSI (4.20)
For 2016-2018, see my summary: [Gregg 18].
Includes CPU schedulers (thermal, topology);
Block I/O qdiscs; Kyber scheduler (earlier slide);
TCP congestion control algoritms (earlier slide); etc.
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Recent Linux perf features
2021: Syscall user dispatch (5.11)
2020: Static calls to improve Spectre-fix (5.10)
2020: BPF on socket lookups (5.9)
2020: Thermal pressure (5.7)
2020: MultiPath TCP (5.6)
2019: MADV_COLD, MADV_PAGEOUT (5.4)
2019: io_uring (5.1)
2019: UDP GRO (5.0)
2019: Multi-queue I/O default (5.0)
2018: TCP EDT (4.20)
2018: PSI (4.20)
For 2016-2018, see my summary: [Gregg 18].
Includes CPU schedulers (thermal, topology);
Block I/O qdiscs; Kyber scheduler (earlier slide);
TCP congestion control algoritms (earlier slide); etc.
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

io_uring
Faster syscalls using
shared ring buffers
Send and completion ring buffers
Allows I/O to be batched and async
Primary use cases network and disk I/O
Apps
syscalls
io_uring
Kernel
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

eBPF Everywhere
[Thaler 21]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)
Plus eBPF for BSD projects already started.

eBPF == BPF
2015:
BPF: Berkeley Packet Filter
eBPF: extended BPF
2021:
“Classic BPF”: Berkeley Packet Filter
BPF: A technology name (aka eBPF)
Kernel engineers like to use “BPF”; companies “eBPF”.
This is what happens when you don’t have marketing professionals help name your product
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

BPF Future: Event-based Applications
User-mode
Applications
Kernel-mode
Applications (BPF)
U.E.
Scheduler
Kernel
Kernel
Events
Hardware Events (incl. clock)
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

https://twitter.com/srostedt/status/1177147373283418112
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Emerging BPF uses
Observability agents
Security agents
TCP congestion control algorithms
Kernel drivers
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Future BPF Uses
File system buffering/readahead policies
CPU scheduler policies
Lightweight I/O-bound applications (e.g., proxies)
Or such apps can go to io_uring or FPGAs. “Three buses arrived at once.”
When I did engineering at University: “people ride buses and electrons ride busses.” Unfortunately that
usage has gone out of fashion, otherwise it would have been clear which bus I was referring to!
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Kernels become JITed
PGO/AutoFDO shows ~10% wins, but hard to manage
Performance-guided optimization (PGO) / Auto feedback-directed optimization (AutoFDO)
Some companies already do kernel PGO (Google [Tolvanen 20], Microsoft [Bearman 20])
We can't leave 10% on the table forever
Kernels PGO/JIT support by default, so it “just works.”
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Kernel emulation often slow
I can run gt; apps under gt;
by emulating gt; syscalls!
Cool project, but:
Missing latest kernel and perf features (E.g., Linux’s BPF, io_uring, WireGuard, etc. Plus certain syscall flags
return ENOTSUP. So it’s like a weird old fork of Linux.)
Some exceptions: E.g., another kernel may have better hardware support, which may benefit apps
more than the loss of kernel capabilities.
Debugging and security challenges. Better ROI with lightweight VMs.
In other words, WSL2 >gt;>gt; WSL1
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: OS performance
Linux: increasing complexity & worse perf defaults
Becomes so complex that it takes an OS team to make it perform well. This assumes that the defaults rot,
because no perf teams are running the defaults anymore to notice (e.g., high-speed network engineers
configure XDP and QUIC, and aren’t looking at defaults with TCP). A bit more room for a lightweight kernel
(e.g., BSD) with better perf defaults to compete. Similarities: Oracle DB vs MySQL; MULTICS vs UNIX.
BSD: high perf for narrow uses
Still serving some companies (including Netflix) very well thanks to tuned performance (see footnote on p124 of
[Gregg 20]). Path to growth is better EC2/Azure performance support, but it may take years before a big
customer (with a perf team) migrates and gets everything fixed. There are over a dozen of perf engineers
working on Linux on EC2; BSD needs at least one full time senior EC2 (not metal) perf engineer.
Windows: community perf improvements
BPF tracing support allows outsiders to root cause kernel problems like never before (beyond ETW/Xperf). Will
have a wave of finding “low hanging fruit” to begin with, improving perf and reliability.
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Unikernels
Finally gets one compelling published use case
“2x perf for X”
But few people run X
Needs to be really kernel heavy, and not many workloads are. And there’s already a lot of competition for
reducing kernel overhead (BPF, io_uring, FPGAs, DPDK, etc.)
Once one use case is found, it may form a valuable community around X and Unikernels. But it needs the
published use case to start, preferably from a FAANG.
Does need to be 2x or more, not 20%, to overcome the cost of retooling everything, redoing all observability
metrics, profilers, etc. It’s not impossible, but not easy [Gregg 16].
More OS-research-style wins found from hybrid- and micro-kernels.
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

7. Hypervisors
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Containers
Cgroup v2 rollout
Container scheduler adoption
Kubernetes, OpenStack, and more
Netflix develops its own called “Titus” [Joshi 18]
Price/performance gains: “Tetris packing” workloads without too much interference (clever scheduler)
Many perf tools still not “container aware”
Usage in a container not restricted to the container, or not permitted by default (needs CAP_PERFMON
CAP_SYS_PTRACE, CAP_SYS_ADMIN)
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Hardware Hypervisors
Source: Systems Performance 2nd Edition, Figure 11.17 [Gregg 20]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

VM Improvements
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)
Source:
[Gregg 17]

Lightweight VMs
E.g., AWS “Firecracker”
Source: Systems Performance 2nd Edition, Figure 11.4 [Gregg 20]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Containers
Perf tools take several years to be fully “container aware”
Includes non-root BPF work.
It’s a lot of work, and not enough engineers are working on it. We’ll use workarounds in the meantime (e.g.,
Kyle Anderson and Sargun Dhillon have made perf tools work in containers at Netflix).
Was the same with Solaris Zones (long slow process).
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Landscape
Short term:
Containers everywhere
Long term:
More containers than VMs
More lightweight VM cores than container cores
Hottest workloads switch to dedicated kernels (no kernel resource sharing, no seccomp overhead, no
overlay overhead, full perf tool access, PGO kernels, etc.)
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Evolution
1.FaaS
Light workload
2.Container
3.Lightweight VM
4.Metal
Heavy workload
Many apps aren’t heavy
Metal can also mean single container on metal
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Cloud Computing
Microservice IPC cost drives need for:
Container schedulers co-locating chatty services
With BPF-based accelerated networking between them (e.g., Cilium)
Cloud-wide runtime schedulers co-locating apps
Multiple apps under one JVM roof and process address space
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

8. Observability
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

2021: Age of Seeing
Flame graphs everywhere
Latency heat maps
eBPF & bpftrace
PMCs in the cloud
More info: flame graphs [Gregg 13], heat maps [Gregg 10],
and eBPF [Gregg 16b]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

BPF Perf Tools
(In red are the new open source
tools I developed for the
BPF book)
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Example BPF tool
# execsnoop.py -T
TIME(s) PCOMM
run
bash
svstat
perl
grep
sed
xargs
cut
echo
mkdir
[...]
run
bash
svstat
perl
[...]
PID
PPID
RET ARGS
0 ./run
0 /bin/bash
0 /command/svstat /service/httpd
0 /usr/bin/perl -e $l=gt;;$l=~/(\d+) sec/;p...
0 /bin/ps --ppid 1 -o pid,cmd,args
0 /bin/grep org.apache.catalina
0 /bin/sed s/^ *//;
0 /usr/bin/xargs
0 /usr/bin/cut -d -f 1
0 /bin/echo
0 /bin/mkdir -v -p /data/tomcat
0 ./run
0 /bin/bash
0 /command/svstat /service/httpd
0 /usr/bin/perl -e $l=gt;;$l=~/(\d+) sec/;p...
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Example bpftrace one-liner
# bpftrace -e 't:block:block_rq_issue { @[args->gt;rwbs] = count(); }'
Attaching 1 probe...
@[R]: 1
@[RM]: 1
@[WFS]: 2
@[FF]: 3
@[WSM]: 9
@[RA]: 10
@[WM]: 12
@[WS]: 29
@[R]: 107
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

libbpf-tools
# ./opensnoop
PID
COMM
27974 opensnoop
redis-server
[…]
FD ERR PATH
0 /etc/localtime
0 /proc/1482/stat
# ldd opensnoop
linux-vdso.so.1 (0x00007ffddf3f1000)
libelf.so.1 =>gt; /usr/lib/x86_64-linux-gnu/libelf.so.1 (0x00007f9fb7836000)
libz.so.1 =>gt; /lib/x86_64-linux-gnu/libz.so.1 (0x00007f9fb7619000)
libc.so.6 =>gt; /lib/x86_64-linux-gnu/libc.so.6 (0x00007f9fb7228000)
/lib64/ld-linux-x86-64.so.2 (0x00007f9fb7c76000)
# ls -lh opensnoop opensnoop.stripped
-rwxr-xr-x 1 root root 645K Feb 28 23:18 opensnoop
-rwxr-xr-x 1 root root 151K Feb 28 23:33 opensnoop.stripped
151 Kbytes for a stand-alone BPF program!
(Note: A static bpftrace/BTF + scripts will also have a small average tool size)
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Modern Observability Stack
OpenTelemetry
Grafana
Standard for monitoring and tracing
Prometheus
Monitoring database
Grafana
UI with dashboards
Source: Figure 1.4 [Gregg 20]
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: BPF tool front-ends
bpftrace
For one-liners and to hack up new tools
When you want to spend an afternoon developing some custom BPF tracing
libbpf-tools
For packaged BPF binary tools and BPF products
When you want to spend weeks developing BPF
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Too many BPF tools
(I’m partly to blame)
2014: I have no tools for this problem
2024: I have too many tools for this problem
Tool creators: Focus on solving something no other tool can. Necessity is the mother of good BPF tools.
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: BPF perf tool future
GUIs, not CLI tools
Tool output, visualized
This GUI is in development by Susie Xia, Netflix
The end user may not even know it’s using BPF
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

My Prediction: Flame scope adoption
Analyze variance, perturbations:
Flame graph
Subsecond-offset heat map
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)
[Spier 20]

Recap
1. Processors
2. Memory
3. Disks
4. Networking
5. Runtimes
6. Kernels
7. Hypervisors
8. Observability
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Performance engineering is getting more complex
1. Processors: CPUs, GPUs, FPGAs, TPUs
2. Memory: DRAM, RLDRAM, HBM, 3D XPoint
3. Disks: PMR, SMR, MAT, EAMR, HAMR, SLC, MLC, ...
4. Networking: QUIC, MP-TCP, XDP, qdiscs, pacing, BQL, ...
5. Runtimes: Choice of JVM, GC, c2/Graal
6. Kernels: BPF, io_uring, PGO, Linux complexity
7. Hypervisors: VMs, Containers, LightweightVMs
8. Observability: BPF, PMCs, heat maps, flame graphs,
OpenTelemetry, Prometheus, Grafana
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

References
[Gregg 08] Brendan Gregg, “ZFS L2ARC,” http://www.brendangregg.com/blog/2008-07-22/zfs-l2arc.html, Jul 2008
[Gregg 10] Brendan Gregg, “Visualizations for Performance Analysis (and More),”
https://www.usenix.org/conference/lisa10/visualizations-performance-analysis-and-more, 2010
[Greenberg 11] Marc Greenberg, “DDR4: Double the speed, double the latency? Make sure your system can handle next-generation
DRAM,” https://www.chipestimate.com/DDR4-Double-the-speed-double-the-latencyMake-sure-your-system-can-handlenext-generation-DRAM/Cadence/Technical-Article/2011/11/22, Nov 2011
[Hruska 12] Joel Hruska, “The future of CPU scaling: Exploring options on the cutting edge,”
https://www.extremetech.com/computing/184946-14nm-7nm-5nm-how-low-can-cmos-go-it-depends-if-you-ask-theengineers-or-the-economists, Feb 2012
[Gregg 13] Brendan Gregg, “Blazing Performance with Flame Graphs,”
https://www.usenix.org/conference/lisa13/technical-sessions/plenary/gregg, 2013
[Shimpi 13] Anand Lal Shimpi, “Seagate to Ship 5TB HDD in 2014 using Shingled Magnetic Recording,”
https://www.anandtech.com/show/7290/seagate-to-ship-5tb-hdd-in-2014-using-shingled-magnetic-recording, Sep 2013
[Borkmann 14] Daniel Borkmann, “net: tcp: add DCTCP congestion control algorithm,”
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?
id=e3118e8359bb7c59555aca60c725106e6d78c5ce, 2014
[Macri 15] Joe Macri, “Introducing HBM,” https://www.amd.com/en/technologies/hbm, Jul 2015
[Cardwell 16] Neal Cardwell, et al., “BBR: Congestion-Based Congestion Control,” https://queue.acm.org/detail.cfm?id=3022184,
[Gregg 16] Brendan Gregg, “Unikernel Profiling: Flame Graphs from dom0,” http://www.brendangregg.com/blog/2016-01-27/unikernelprofiling-from-dom0.html, Jan 2016
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

References (2)
[Gregg 16b] Brendan Gregg, “Linux BPF Superpowers,” https://www.brendangregg.com/blog/2016-03-05/linux-bpf-superpowers.html,
[Alcorn 17] Paul Alcorn, “Seagate To Double HDD Speed With Multi-Actuator Technology,” https://www.tomshardware.com/news/hddmulti-actuator-heads-seagate,36132.html, 2017
[Alcorn 17b] Paul Alcorn, “Hot Chips 2017: Intel Deep Dives Into EMIB,” https://www.tomshardware.com/news/intel-emib-interconnectfpga-chiplet,35316.html#xenforo-comments-3112212, 2017
[Corbet 17] Jonathan Corbet, “Two new block I/O schedulers for 4.12,” https://lwn.net/Articles/720675, Apr 2017
[Gregg 17] Brendan Gregg, “AWS EC2 Virtualization 2017: Introducing Nitro,” http://www.brendangregg.com/blog/2017-11-29/awsec2-virtualization-2017.html, Nov 2017
[Russinovich 17] Mark Russinovich, “Inside the Microsoft FPGA-based configurable cloud,”
https://www.microsoft.com/en-us/research/video/inside-microsoft-fpga-based-configurable-cloud, 2017
[Gregg 18] Brendan Gregg, “Linux Performance 2018,” http://www.brendangregg.com/Slides/Percona2018_Linux_Performance.pdf,
[Hady 18] Frank Hady, “Achieve Consistent Low Latency for Your Storage-Intensive Workloads,”
https://www.intel.com/content/www/us/en/architecture-and-technology/optane-technology/low-latency-for-storageintensive-workloads-article-brief.html, 2018
[Joshi 18] Amit Joshi, et al., “Titus, the Netflix container management platform, is now open source,” https://netflixtechblog.com/titusthe-netflix-container-management-platform-is-now-open-source-f868c9fb5436, Apr 2018
[Cutress 19] Dr. Ian Cutress, “Xilinx Announces World Largest FPGA: Virtex Ultrascale+ VU19P with 9m Cells,”
https://www.anandtech.com/show/14798/xilinx-announces-world-largest-fpga-virtex-ultrascale-vu19p-with-9m-cells, Aug
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

References (3)
[Gallatin 19] Drew Gallatin, “Kernel TLS and hardware TLS offload in FreeBSD 13,”
https://people.freebsd.org/~gallatin/talks/euro2019-ktls.pdf, 2019
[Redestad 19] Claes Redestad, Staffan Friberg, Aleksey Shipilev, “JEP 230: Microbenchmark Suite,” http://openjdk.java.net/jeps/230,
updated 2019
[Bearman 20] Ian Bearman, “Exploring Profile Guided Optimization of the Linux Kernel,”
https://linuxplumbersconf.org/event/7/contributions/771, 2020
[Burnes 20] Andrew Burnes, “GeForce RTX 30 Series Graphics Cards: The Ultimate Play,”
https://www.nvidia.com/en-us/geforce/news/introducing-rtx-30-series-graphics-cards, Sep 2020
[Charlene 20] Charlene, “800G Is Coming: Set Pace to More Higher Speed Applications,” https://community.fs.com/blog/800-gigabitethernet-and-optics.html, May 2020
[Cutress 20] Dr. Ian Cutress, “Insights into DDR5 Sub-timings and Latencies,” https://www.anandtech.com/show/16143/insights-intoddr5-subtimings-and-latencies, Oct 2020
[Ford 20] A. Ford, et al., “TCP Extensions for Multipath Operation with Multiple Addresses,”
https://datatracker.ietf.org/doc/html/rfc8684, Mar 2020
[Gregg 20] Brendan Gregg, “Systems Performance: Enterprise and the Cloud, Second Edition,” Addison-Wesley, 2020
[Hruska 20] Joel Hruska, “Intel Demos PCIe 5.0 on Upcoming Sapphire Rapids CPUs,”
https://www.extremetech.com/computing/316257-intel-demos-pcie-5-0-on-upcoming-sapphire-rapids-cpus,
Oct 2020
[Liu 20] Linda Liu, “Samsung QVO vs EVO vs PRO: What’s the Difference? [Clone Disk],”
https://www.partitionwizard.com/clone-disk/samsung-qvo-vs-evo.html, 2020
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

References (4)
[Moore 20] Samuel K. Moore, “A Better Way to Measure Progress in Semiconductors,”
https://spectrum.ieee.org/semiconductors/devices/a-better-way-to-measure-progress-in-semiconductors, Jul 2020
[Peterson 20] Zachariah Peterson, “DDR5 vs. DDR6: Here's What to Expect in RAM Modules,” https://resources.altium.com/p/ddr5-vsddr6-heres-what-expect-ram-modules, Nov 2020
[Salter 20] Jim Salter, “Western Digital releases new 18TB, 20TB EAMR drives,” https://arstechnica.com/gadgets/2020/07/westerndigital-releases-new-18tb-20tb-eamr-drives, Jul 2020
[Spier 20] Martin Spier, Brendan Gregg, et al., “FlameScope,” https://github.com/Netflix/flamescope, 2020
[Tolvanen 20] Sami Tolvanen, Bill Wendling, and Nick Desaulniers, “LTO, PGO, and AutoFDO in the Kernel,” Linux Plumber’s
Conference, https://linuxplumbersconf.org/event/7/contributions/798, 2020
[Vega 20] Juan Camilo Vega, Marco Antonio Merlini, Paul Chow, “FFShark: A 100G FPGA Implementation of BPF Filtering for
Wireshark,” IEEE 28th Annual International Symposium on Field-Programmable Custom Computing Machines (FCCM) ,
[Warren 20] Tom Warren, “Microsoft reportedly designing its own ARM-based chips for servers and Surface PCs,”
https://www.theverge.com/2020/12/18/22189450/microsoft-arm-processors-chips-servers-surface-report, Dec 2020
[Alcorn 21] Paul Alcorn, “Intel Shares Alder Lake Pricing, Specs and Gaming Performance: $589 for 16 Cores,”
https://www.tomshardware.com/features/intel-shares-alder-lake-pricing-specs-and-gaming-performance, Oct 2021
[Cutress 21] Ian Cutress, “AMD Demonstrates Stacked 3D V-Cache Technology: 192 MB at 2 TB/sec,”
https://www.anandtech.com/show/16725/amd-demonstrates-stacked-vcache-technology-2-tbsec-for-15-gaming, May 2021
[Google 21] Google, “Cloud TPU,” https://cloud.google.com/tpu, 2021
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

References (5)
[Haken 21] Michael Haken, et al., “Delta Lake 1S Server Design Specification 1v05, https://www.opencompute.org/documents/deltalake-1s-server-design-specification-1v05-pdf, 2021
[Intel 21] Intel corporation, “Intel® OptaneTM Technology,” https://www.intel.com/content/www/us/en/products/docs/storage/optanetechnology-brief.html, 2021
[Kostovic 21] Aleksandar Kostovic, “Esperanto Delivers Kilocore Processor in its Supercomputer-on-a-Chip Design,”
https://www.tomshardware.com/news/esperanto-kilocore-processor, Aug 2021
[Kummrow 21] Patricia Kummrow, “The IPU: A New, Strategic Resource for Cloud Service Providers,”
https://itpeernetwork.intel.com/ipu-cloud/#gs.g5pkub, Aug 2021
[Quach 21a] Katyanna Quach, “Global chip shortage probably won't let up until 2023, warns TSMC: CEO 'still expects capacity to
tighten more',” https://www.theregister.com/2021/04/16/tsmc_chip_forecast, Apr 2021
[Quach 21b] Katyanna Quach, “IBM says it's built the world's first 2nm semiconductor chips,”
https://www.theregister.com/2021/05/06/ibm_2nm_semiconductor_chips, May 2021
[Ridley 21] Jacob Ridley, “IBM agrees with Intel and TSMC: this chip shortage isn't going to end anytime soon,”
https://www.pcgamer.com/ibm-agrees-with-intel-and-tsmc-this-chip-shortage-isnt-going-to-end-anytime-soon, May 2021
[Shilov 21] Anton Shilov, “Samsung Develops 512GB DDR5 Module with HKMG DDR5 Chips,”
https://www.tomshardware.com/news/samsung-512gb-ddr5-memory-module, Mar 2021
[Shilov 21b] Anton Shilov, “Seagate Ships 20TB HAMR HDDs Commercially, Increases Shipments of Mach.2 Drives,”
https://www.tomshardware.com/news/seagate-ships-hamr-hdds-increases-dual-actuator-shipments, 2021
[Shilov 21c] Anton Shilov, “SK Hynix Envisions 600-Layer 3D NAND & EUV-Based DRAM,” https://www.tomshardware.com/news/skhynix-600-layer-3d-nand-euv-dram, Mar 2021
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

References (6)
[Shilov 21d] Anton Shilov, “Sapphire Rapids Uncovered: 56 Cores, 64GB HBM2E, Multi-Chip Design,”
https://www.tomshardware.com/news/intel-sapphire-rapids-xeon-scalable-specifications-and-features, Apr 2021
[SuperMicro 21] SuperMicro, “B12SPE-CPU-25G (For SuperServer Only),”
https://www.supermicro.com/en/products/motherboard/B12SPE-CPU-25G, 2021
[Thaler 21] Dave Thaler, Poorna Gaddehosur, “Making eBPF work on Windows,”
https://cloudblogs.microsoft.com/opensource/2021/05/10/making-ebpf-work-on-windows, May 2021
[TornadoVM 21] TornadoVM, “TornadoVM Run your software faster and simpler!” https://www.tornadovm.org, 2021
[Trader 21] Tiffany Trader, “Cerebras Second-Gen 7nm Wafer Scale Engine Doubles AI Performance Over First-Gen Chip ,”
https://www.enterpriseai.news/2021/04/21/latest-cerebras-second-gen-7nm-wafer-scale-engine-doubles-ai-performanceover-first-gen-chip, Apr 2021
[Vahdat 21] Amin Vahdat, “The past, present and future of custom compute at Google,”
https://cloud.google.com/blog/topics/systems/the-past-present-and-future-of-custom-compute-at-google, Mar 2021
[Wikipedia 21] “Semiconductor device fabrication,” https://en.wikipedia.org/wiki/Semiconductor_device_fabrication, 2021
[Wikipedia 21b] “Silicon,” https://en.wikipedia.org/wiki/Silicon, 2021
[ZonedStorage 21] Zoned Storage, “Zoned Namespaces (ZNS) SSDs,” https://zonedstorage.io/introduction/zns, 2021
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)

Thanks
Thanks for watching!
Slides: http://www.brendangregg.com
Thanks to colleagues Jason Koch, Sargun Dhillon, and Drew Gallatin for their
performance engineering expertise.
Thanks to YOW organizers!
YOW! Computing Performance 2021: What’s On the Horizon (Brendan Gregg)