Information here is by rumor, innuendo and extrapolation. Manufacturers rarely put info on packet buffers in their data sheets. There are some summary thoughts

The buffer size question discussed in 2012 on the nanog list and is reproduced. Buffer requirements for long RTT networks is less well understood than you might hope. IETF tests for burst management are not as well developed as bandwidth tests. There is a draft that hints at progress. Packet pacing can improve buffer effectiveness by making TCP less bursty.

Packet buffers and switch performance have shown steady improvement. This table attempts to show this for ASICs with integrated packet buffers and why using crufty old stuff is at your peril.

Incast is a buffer exhaustion phenomena that is one consequence of running out of packet memory.

Shared memory means that the hardware permits buffers to be used by any port that needs them. An intel white paper compares shared memory with other architectures. In a shared memory design it is not possible to let ALL the memory go to queued packets. There would be no room for new arrivals which would lead to head of line blocking. The other major option for a switch fabric is a crossbar matrix.

Buffer queue depth monitoring cannot be done directly with SNMP MIB-II polling of the current occupancy of the buffer. Even if a buffer depth SNMP poll object existed it would not possible to interrogate it on a time scale short enough to catch microbursts. A burst that would fill a 4 MByte buffer would completely drain in 3.2 mS at 10 Gb/s. You could hope for indirect evidence of buffer exhaustion by monitoring packet drops. Bursts too short to cause drops can nonetheless be long enough to affect performance. Direct queue monitoring can thus add valuable information.

Some switches have multiple switch ICs that each manage their own memory pool. Examples are the Brocade FCX648S and the Cisco 3750-48. Memory from one IC can be shared among the ports in that IC's group but cannot be loaned out to ports controlled by other switch chips. Here we are interested in queue resources that can be claimed by a single flow for burst absorption -- not the total RAM in the system.

Tolly (tolly.com) occasionally reports on the ability of switches to sustain microbursts in his reports on data center switches. These measurements relate directly to output port buffering. See esp the IBM G8264 below.

Max buffer queue depth requires that all packet memory can be put into a single queue. QoS schemes divide buffer resources among defined queues. As such, I am not interested in the QoS descriptions and these are even less reliable than the rest of this doc.

Model

Port Type

RX Queue

TX Queue

Total Buffer

RX Buffer

TX Buffer

Trident+ Shared Memory

Accton 5652

48 SFP+ and 4 QSFP+

8Q

9 MB

5? MB

Juniper QFX3500

48 SFP+ and 4 QSFP+

8Q

9 MB

5 MB

Arista 7050S-64

48 SFP+ and 4 QSFP

8Q

9 MB/switch

5 MB

Dell 8132F & 4032F

24 SFP+ and 2 x QSFP+

8Q

9 MB

Dell 8164F & 4064F

48 SFP+ and 4 x QSFP+

8Q

9 MB

Pica8 P-3920

48 SFP+ and 4 x QSFP+

9 MB

Penguin 4804x

48 SFP+ and 4 x QSFP+

9 MB

Cisco Nexus 3064X

48 SFP+ and 4 QSFP+

12Q

9 MB

5 MB

Supermicro SSE-X3348T

48 10GTw-Pr and 4 QSFP+

8Q

9 MB

Supermicro SSE-X3348S

48 SFP+ and 4 QSFP+

8Q

9 MB

IBM G8264

48 SFP+ and 4 QSFP+

8Q

9 MB/switch

not on data sheet

Force10 S4810

48 SFP+ and 4 QSFP+

4Q

9 MB

Allied Telesis DC2552

48 SFP+ and 4 QSFP+

8Q

9 MB

5 MB

NEC PF5820

48 SFP+ and 4 QSFP+

HP 5900AF-48XG-4QSFP+

48 SFP+ and 4 QSFP+

9 MB

Edge-core-AS5600-52X

48 SFP+ and 4 QSFP+

9 MB

Cisco Nexus 3048

48 1000-base-T and 4 SFP+

8Q

9 MB but see notes

5? MB to 1 port

Brocade TOR custom

Brocade VDX 6740

48 SFP+ and 4 QSFP+

24 MB

Dynamic up to 8 MB

Dynamic up to 8 MB

Brocade VDX 6940

96 SFP+ and 12 QSFP+

24 MB

Dynamic up to 8 MB

Dynamic up to 8 MB

Trident II and II+

Champion Trident2

varies by model

12.2 MB

Lenovo G8272

48 SFP+ and 6 QSFP+

12.2 MB

Arista 7050X

32 QSFP+

8Q

12 MB

Dynamic up to 8 MB

Arista 7250X

64 QSFP+

8Q

12 MB/ASIC, 48 MB total

Dynamic up to 8 MB

Arista 7300X 4/8/16 slot chassis

16 slot: 512 QSFP

8Q

12 MB/ASIC

Dynamic up to 8 MB

Brocade 7750-26Q

26 QSFP+ and slot

8Q

12.2 MB

Dynamic up to 8 MB

Brocade 7750-48F

48 SFP+ and 6 QSFP+ and expansion

8Q

12.2 MB

Dynamic up to 8 MB

Brocade 7750-48C

48 10GbaseT and 6 QSFP+ and expansion

8Q

12.2 MB

Dynamic up to 8 MB

Quanta BMS T3048-LY8

48 SFP+ and 6 QSFP+

8Q

12 MB

8 MB

Pluribus E68

44 SFP+ and 6 QSFP+

8Q

Extreme Summit 770

32 QSFP+

8Q

No info

No info

Cisco Nexus 3132Q

32 QSFP+ or 31 QSFP+ and 4 SFP+

8Q

12.2 MB

Dynamic up to 8 MB

Cisco Nexus 3172PQ

48 SFP+ and 6 QSFP+

8Q

12.2 MB

Dynamic up to 8 MB

Dell-S4048-ON

48 SFP+ and 6 QSFP+

8Q

12 MB

Dynamic up to 8 MB

Dell S6000

32 QSFP+

8Q

12 MB

Dynamic up to 8 MB

Juniper QFX5100-24Q

24 QSFP+ + expansion slots

8Q

12 MB

Dynamic up to 8 MB

Juniper EX4600

24 SFP+ + 4 QSFP + expansion slots

8Q

12 MB

Dynamic up to 8 MB

HP 5930

32 QSFP+

8Q

12.2 MB

Dynamic up to 8 MB

HP 5930 w 2 modules

48 SFP+ and 4 QSFP+

8Q

12.2 MB

Dynamic up to 8 MB

HP Altoline 5712

48 SFP+ and 6 QSFP+

8Q

12.2 MB

Dynamic up to 8 MB

HP Altoline 6712

32 QSFP+

8Q

12.2 MB

Dynamic up to 8 MB

Accton Edge-corE AS5712-54X

48 SFP+ and 6 QSFP+

8Q

12.2 MB

Dynamic up to 8 MB

Accton Edge-corE AS6712-32X

32 QSFP+

8Q

12.2 MB

Dynamic up to 8 MB

Inventec D6232Q

48 SFP+ and 6 QSFP+

8Q

12.2 MB

Dynamic up to 8 MB

Wedge - Facebook OCP

16 QSFP+

8Q

12.2 MB

Dynamic up to 8 MB

Trident II+

Alpha Networks SNX-60x0-486x

48 SFP+ and 4 QSFP28 100G and 2 QSFP+

8Q

16 MB

Dynamic up to 12 MB

Artica 4806xp

48 SFP+ and 6 QSFP 40G

8Q

16 MB

Dynamic up to 12 MB

Champion Trident2+

Three switch configurations

8Q

16 MB

Arista 7050X2 family

see table

8Q

16 MB

Dynamic up to 12 MB

Dell S4048T-ON

48 10G-BASE-T and 6 x QSFP+

8Q

16 MB

Dynamic up to 12 MB

Dell S6010-ON

32 40-Gbps QSFP

8Q

16 MB

Dynamic up to 12 MB

Cisco Nexus 3132Q-V

32 QSFP+ or 26 QSFP+ and 6 QSFP28

8Q

16 MB

Dynamic up to 12 MB

Cisco Nexus 31108PC-V

48 SFP+ and 6 QSFP28

8Q

16 MB

Dynamic up to 12 MB

Cisco NCS5001

40 1/10-Gbps SFP+ and 4 QSFP28 100G

8Q

16 MB

Dynamic up to 12 MB

Cisco NCS5002

80 1/10-Gbps SFP+ and 4 QSFP28 100G

8Q

16 MB

Dynamic up to 12 MB

EdgeCore AS6812-32X

32 40-Gbps QSFP+

8Q

16 MB

Dynamic up to 12 MB

Accton Edge-corE AS5812-54X

48 SFP+ and 6 QSFP+

8Q

16 MB

Dynamic up to 12 MB

HPE Altoline 6921-54X

48 SFP+ and 6 QSFP+

8Q

16 MB??

Dynamic up to 12 MB

Juniper QFX5110-48S

48 SFP+ and 4 QSFP28 100G

8Q

16 MB

Dynamic up to 12 MB

Extreme Networks VSP 8404C 4-slot modular

2-port 100Gb/s module, 8-port QSFP module, . . .

8Q

Trident 3

Arista 7050CX3-32S

32 port 100G QSFP28 and 2 port 10 Gb/s

8Q

32 MB

27 MB shared pool

Arista 7050SX3-48YC12

48 port 25G SFP28 and 12 port 100 Gb/s

8Q

32 MB

27 MB shared pool

Edgecore AS7326-56X

48 port 25G SFP28 and 8 port 100 Gb/s

8Q

32 MB

QuantaMesh BMS T4048-IX8

48 port 25G SFP28 and 8 port 100 Gb/s

8Q

32 MB

QuantaMesh BMS T7032-IX7

32 port 100G QSFP28

8Q

32 MB

Alpha SNC-60x0-488F

48 port 25G SFP28 and 8 port 100 Gb/s

8Q

Dell S5248

48 port 25 Gb/s SFP28 and ??? 100G QSFP28

8Q

32 MB

Cisco C3132C-Z

32 port 100 Gb/s QSFP28

8Q

32 MB

Nephos 8360 Taurus family

Liteon-LS3048-SN1

48 port 10G QSFP and 6 port 100 Gb/s

8Q

options: 20-50 Mbyte

Nephos-AS7116-54X

48 port 25G QSFP28 and 6 port 100 Gb/s

8Q

options: 20-50 Mbyte

Ingrasys S9130-32X

32 port 100G QSFP28

8Q

options: 20-50 Mbyte

Ingrasys S9230-32X

64 port 100G QSFP28

8Q

options: 20-50 Mbyte

Broadcom Maverick

Alpha Networks SNX-61A0-486T

48 10G-base-T and 4 QSFP28 and 2 QSFP

8Q

?? MB

Alpha Networks SNX-61A0-486F

48 SFP+ and 4 QSFP28 and 2 QSFP

8Q

?? MB

Dell S4148F-ON

48 port SFP+ and 2 QSFP+ and 2 QSFP28

8Q

12 MByte

8 MB

QCT QuantaMesh T3048 LY7

48 port SFP+ and 4 QSFP28

8Q

12 MByte

8 MB

Broadcom Tomahawk

Penguin 3200C

32 port QSFP28 100 Gb/s

8Q

16 MByte

Est 3 MByte per core

Dell Z9100

32 port QSFP28 100 Gb/s

8Q

16 MByte

Est 3 MByte per core

Dell S6100-ON

Depends on modules selected.

8Q

16 MByte

Est 3 MByte per core

Dell S5148

48 port SFP28+ 25 Gb/s + 6 x 100G

8Q

16 MByte

Est 3 MByte per core

Cisco Nexus 3232C

32 port QSFP28 100 Gb/s

8Q

16 MByte

Est 3 MByte per core

Cisco NCS5011

32 QSFP28 100G

8Q

16 MByte

Est 3 Mbyte per core

Arista 7060CX-32

32 port QSFP28 100 Gb/s and 2 SFP+

8Q

16 MByte

Est 3 MByte per core

Arista 7260CX-64

64 port QSFP28 100 Gb/s and 2 SFP+

8Q

64 MByte

Est 3 MByte per core

Arista 7320X

256 port QSFP28 100 Gb/s

8Q

64 MByte

Est 3 MByte per core

Juniper QFX5200-32C

32 port QSFP28 100 Gb/s

8Q

16 MByte

Est 3 MByte per core

Juniper QFX5200-64Q

32 port QSFP28 OR 64 QSFP

8Q

16 MByte

Est 3 MByte per core

Aurora 620 with ONIE

48 SFP28 25 Gb/s and 6 QSFP28 100 G

8Q

16 MByte

Est 3 MByte per core

Aurora 720 with ONIE

32 QSFP28 100 Gb/s

8Q

16 MByte

Est 3 MByte per core

Inventec D7032Q28B

32 QSFP28 100 Gb/s

8Q

16 MByte

Est 3 MByte per core

Edge-core-7710 and 7712

32 QSFP28 100 Gb/s

8Q

16 MB

Est 3 Mbyte per core

Champion Tomahawk

32 QSFP28 100 Gb/s

HP 6960

32 QSFP28 100 Gb/s

8Q

16 MB

Est 3 Mbyte per core

Quanta T4048-IX2

48 x SFP28 + 8 x QSFP28/s

8Q

16 MB

Est 3 Mbyte per core

Agema AG5648

6 QSFP28 100 Gb/s and 48 SFP28 25 Gb/s

8Q

16 MB

Est 3 Mbyte per core

Agema AG9032

32 QSFP28 100 Gb/s

8Q

16 MB

Est 3 Mbyte per core

Facebook OCP Backpack

128 QSFP28 100 Gb/s

8Q

256 MB

Est 3 Mbyte per core

Edge-core 7812-24S

16 QSFP28 AND 8 200 Gb/s coherent

8Q

Est 3 Mbyte per core

Broadcom Tomahawk-+

fs.com N8500-48B6C

48 SFP28 25 Gb/s and 6 QSFP28 100 Gb/s

8Q

16 MB

Agema AG5648V1

48 SFP28 25 Gb/s and 6 QSFP28 100 Gb/s

8Q

16 MB

Edge-core AS7312-54X

48 SFP28 and 6 QSFP28

8Q

?? MB

Est 4.5 Mbyte per core

Alpha Networks SNC-60x0-486F

48 SFP28 25 Gb/s and 6 QSFP28 100 Gb/s

8Q

?? MB

Arista 7060CX2-32S

32 QSFP28 100 Gb/s AND 2 SFP+

8Q

22 MB

Est 4.5 Mbyte per core

Lenovo NE2572

48 SFP28 25 Gb/s AND 6 QSFP28

8Q

22 MB

Est 4.5 Mbyte per core

Broadcom Tomahawk-II

Arista 7260QX-64

64 QSFP 40 Gb/s AND 2 SFP+

8Q

16 MB

Est 3 Mbyte per core

Arista 7260CX3-64

64 QSFP28 100Gb/s AND 2 SFP+

8Q

42 MB

10.5 Mbyte per slice

Agema AG9064

64 QSFP28 100 Gb/s AND 2 SFP+

8Q

16 MB

Est 3 Mbyte per core

Edge-core AS7816-64X

64 QSFP28 100 Gb/s AND 2 SFP+

8Q

42 MB

Est 10.5 Mbyte per slice

Cisco Nexus C3264C-E

64 QSFP28 100 Gb/s AND 2 SFP+

8Q

42 MB

Est 10.5 Mbyte per slice

Broadcom Tomahawk 3

Edgecore AS7900-32X

32 x QSFP-DD 400 Gb/s ports

Arista 7060PX4-32

32 x OSFP 400 Gb/s ports

64 MB

Arista 7060DX4-32

32 x QSFP-DD 400 Gb/s ports

64 MB

Innovium Teralynx Hot new chip to take over the world [2017 OCP]

Cisco C3432D-S

32 x QSFP-DD 400 Gb/s ports + 2 x SFP

70 MB

Cisco Nexus 3408-S

8-slot chassis w 4-port 400G and 16-port 100G cards

70 MB

Broadcom Jericho a member of the StrataDNX DUNE family -- includes Qumran

Cisco NCS 5508

288 QSFP28 100 Gb/s ports

4 GByte per ASIC

VoQ 10 mS per queue

Cisco NCS 5501

six QSFP28 100 Gb/s ports and 48 x 10 Gb/s

4 GByte per ASIC

VoQ 10 mS per queue

Cisco Nexus N9K-X9636C-R

36 x 100 Gb/s QSFP28 linecard

4 GByte per ASIC

VoQ

Cisco Nexus N9K-X9636Q-R

36 x 40 Gb/s QSFP linecard

4 GByte per ASIC

VoQ

Arista 7500R Linecard 36CQ

36 x QSFP28 100G

8Q

24 GB

VoQ

Arista 7500R Linecard 36Q

30 x 40G QSFP and 6 x 100G

8Q

8 GB

VoQ

Arista 7500R Linecard 48S2CQ

48 port sfp+ and 2 x 100G

8Q

4 GB

VoQ

Arista 7280SR-48C6

48 x 10 G SFP+ and 6 x QSFP28

8Q

4 GB

4 GB VoQ

VoQ

Arista 7280TR-48C6

48 x 10GBASE-T and 6 x QSFP28

8Q

4 GB

4 GB VoQ

VoQ

Arista 7280QR-C36

24 QSFP+ and 12 QSFP28

8Q

8 GB

8 GB in 2 groups

VoQ

Arista 7280QR-C48

48 QSFP+ and 24 QSFP28

8Q

32 GB

32 GB in 8 groups

VoQ

Brocade SLX-9850

36 QSFP28 per linecard

8Q

4 or 6 GB per 6-port group VoQ

Brocade SLX-9540

6 QSFP28 100/40 Gb/s and 48 10/1 Gb/s

8Q

6 GB

6 GB VoQ

Edge-Core AS5900-54X

48 SFP+ and 6 QSFP28

8Q

4 GB

VoQ

Champion Qumran

48 SFP+ and 6 QSFP28

8Q

4 GB

VoQ

Alpha STX-60x0-486F Qumran

48 SFP+ and 6 QSFP28

8Q

4 GB

VoQ

Dell S4248-ON

48 SFP+ and 6 QSFP28

8Q

4 GB

VoQ

Extreme VSP8600 - 8 slot chassis

modules: 6 x 100G, 16 x 40G, 24 x 10G

Agema AGC7648A

48 SFP+ and 6 QSFP28

8Q

6 GB

VoQ

Broadcom Jericho+ a member of the StrataDNX DUNE family

Agema AGC5648 Jericho+

48 SFP28+ and 6 QSFP28

8Q

8 GB per ASIC

VoQ

Cisco 3636C-R

36 ea QSFP28 100 Gb/s

8Q

4 GB per ASIC

VoQ

Arista 7280SR2A-48YC6

48 x 25 G SFP28 and 6 x QSFP28

8Q

8 GB

8 GB VoQ

VoQ

Arista 7500R2-36CQ

36 x QSFP28 100 Gb/s

8Q

4 GByte per ASIC

VoQ

Broadcom Jericho2 a member of the StrataDNX DUNE family

Broadcom ARAD (July 2014) a member of the StrataDNX DUNE family

Arista 7280E-64

48 port SFP+ and 4 x QSFP

8Q

9 GB

VoQ 125 MB per 10 gig port

Arista 7280E-68

48 port SFP+ and 2 x QSFP28 100 Gb/s

8Q

9 GB

VoQ 125 MB per 10 gig port

Arista 7280E-72

48 port SFP+ and 2 x MXP

8Q

9 GB

VoQ 125 MB per 10 gig port

Arista 7504E/7508E

48 port sfp+ line card

8Q

3 GB per each of 3 processors

50 MB/port-queue

VoQ

Arista 7504E Linecard 12CQ

12 QSFP28 100G

8Q

3 GB per each of 6 processors

500 MB/port-queue

VoQ

EZChip NP-5

PARPRO N5R-100

24 SFP+ and 4 QSFP+

??

12 GByte

VoQ very large

Cavium

Edge-corE AS7500-32X

32 QSFP28 100 Gb/s

??

24 MB

Edge-corE AS7512-54X

6 QSFP28 100 Gb/s and 48 SFP28

??

24 MB

Wedge_100C

32 QSFP28 100 Gb/s

??

24 MB

Arista 7160 family

32 QSFP28 100 Gb/s

??

24 MB

Brocade SLX-9240

32 QSFP28 100 Gb/s

??

24 MB

Brocade SLX-9140

6 QSFP28 100 Gb/s and 48 QSFP28

??

24 MB

Pegatron w/out model num

6 QSFP28 100 Gb/s and 48 QSFP28

??

24 MB

Barefoot Tofino

Wedge 100BF-32X

32 x QSFP28 100G

16 MByte

16 Mbyte

Wedge 100BF-65X

65 x QSFP28 100G

16 MByte

16 Mbyte

OSW 1800

48 x SFP28 25G and 6 x QSFP28 100G

16 MByte

16 Mbyte

Aurora 710

32 x QSFP28 and 2x SFP+

20 MByte

20 Mbyte

Arista 7170-64C

64 x QSFP28

22 MByte

20 Mbyte

Cisco Nexus C34180

48 x SFP28 and 6 x QSFP28

20 MByte

20 Mbyte

Arista 7170-32C

32 x QSFP28

22 MByte

20 Mbyte

A mystery (for now)

Telco Systems T-Metro-8100

2 x QSFP28 100G and 48 x SFP+ 10G

Huawei S6720-54C-EI-48S

48 SFP+ and 2 QSFP and 4 QSFP expansion

??

8 MB to 1 port

Huawei S6720-30C-EI-24S

24 SFP+ and 2 QSFP and 4 QSFP expansion

??

8 MB to 1 port

Mellanox

Mellanox SX1024

48 SFP+ and 12 QSFP+

??

4.6 MB

64 KB to 1 port

Mellanox SX1036

36 QSFP+

??

4.6 MB

128 KB to 1 port

Mellanox Spectrum

32 QSFP28 100Gb/s

??

16 MB

12 MB to 1 port?

Mellanox Spectrum-2

Broadcom Helix

Arista 7010T

48 1000-base-T + 4 SFP+

8Q

4 MB/switch

4 MB

Brocade ICX 7150-24

(24+2) 1000-base-T and 4 SFP+

8Q

2 MB

2 MB to 1 port

Brocade ICX 7250-24

(24+2) 1000-base-T and 4 SFP+

8Q

2 MB

2 MB to 1 port

Brocade ICX 7650-48P

48 x 1000bsseT and (2 x 40G or 4 x 10G front module)

8Q

5 MB

Brocade ICX 7650-48ZP

24 x 1000BaseT and 24 multiGig ports and (1 x 100G or 2 x 40G front module)

8Q

12 MB

HPE Altoline 6900

48 1000-base-T and 4 SFP+ and 2 QSFP stacking ports

8Q

4 MB

? MB to 1 port

Champion helix4

48 1000-base-T and 4 SFP+ and 2 QSFP stacking ports

8Q

4 MB

Dell S3048-ON

48 1000-base-T and 4 SFP+

8Q

4 MB

? MB to 1 port

Agema AG6248C

48 1000-base-T w 2 SFP+

8Q

4 MB

? MB to 1 port

Centec

Centec V580-20Q4Z and E580-20Q4Z

20 x QSFP 40G and 4 x SFP+ and 4 x QSFP28 100G

9 MB

Centec V580-48X2Q4Z and E580-48X2Q4Z

48 x SFP+ 10G and 2 x QSFP+ 40G and 4 x QSFP28 100G

9 MB

Centec V350-48T4X and E350-48T4X

48 x 1000baeT and 4 x QSFP+ 40G and 4 x QSFP28 100G

3 MB

Centec E330-52SX

48 x SFP 1G and 4 x SFP+ 10G

6 MB

Cisco UADP Catalyst

Catalyst 3850, 3650

ASIC support 24 GE ports AND 2 x 10GE

8Q

several

6 MB per ASIC

4 MB per ASIC

Catalyst C3850-12XS

12 SFP+ (6 ports per ASIC)

8Q

2P6Q3T

6 MB per ASIC

4 MB per ASIC

Catalyst C9300-24T

ASIC support 24 GE ports AND uplink module

8Q

2P6Q3T

not clear

Catalyst C9300-48T

48 GE ports AND uplink module

8Q

2P6Q3T

not clear

Catalyst C9300-24UX

24 100/1G/2.5G/5G/10G Tw-Pr ports AND uplink module

8Q

2P6Q3T

not clear

Catalyst C9500-24Q

24 QSFP 40 Gb/s

8Q

2P6Q3T

not clear

Catalyst C9500-40X

24 SFP+ ports AND uplink module

8Q

2P6Q3T

not clear

Catalyst C9500-24Y4C [UADP 3.0]

24 SFP28 ports AND 4 QSFP28 100G

8Q

2P6Q3T

36 MB per ASIC

est 23 MB

Catalyst C9500-32QC [UADP 3.0]

16 x QSFP28 100G OR 32 QSFP 40G

8Q

2P6Q3T

36 MB per ASIC

est 23 MB

Catalyst C9500-32C [UADP 3.0]

32 SFP28 100G ports

8Q

2P6Q3T

36 MB per ASIC

est 23 MB

Catalyst C9500-48Y4C [UADP 3.0]

48 SFP+ ports AND 4 QSFP28 100G

8Q

2P6Q3T

36 MB per ASIC

est 23 MB

Other Shared Memory

Catalyst 3550-24

24 10/100-base-T + 2 x 1G GBIC

8Q

2 MB

2 MByte

Ciena 3930

2 x SFP+ and 4 SFP and 4 SFP-or-TwPr (10/100/1000)

8Q

Extreme X450-G2-48T-10G

48 1000-base-T + 4 x 10G SFP+

8Q

4 MB

?

Extreme 620X-16

16 10-Gbps SFP+

8Q

2 MB

2 MB

Extreme 620X-10

10 10-Gbps SFP+

8Q

2 MB

2 MB

Cisco Nexus 92160YC-X

48 SFP28 and 6 QSFP28

Single ASE3 20 MByte

10.2 MB

Cisco Nexus 9272Q

2RU 72 x 40Gb/s QSFP+

Single ASE2 30 Mbyte

5.1 MB

Cisco Nexus 9372TX

48 10-Gbps BASE-T and 4 QSFP+

12 MB NFE + 25 MB ALE

21 MB max burst

Cisco Nexus 9396PX

48 SFP+ and {12 QSFP+ or 4 CPAK 100G}

12 MB NFE + 40 MB ALE

21 MB max burst

Cisco Nexus 93180YC-EX

48 SFP28 25 Gb/s and 6 QSFP28

40 MByte

17.6 MB

Cisco Nexus 93108TC-EX

48 tw-pr 10 Gb/s and 6 QSFP28

40 MByte

17.6 MB

Cisco Nexus N9K-C9316D-GX

16 QSFP-DD 400/100 Gb/s

80 MByte

Cisco Nexus N9K-C93600CD-GX

28 SFP28 and 8 QSFP28-DD

80 MByte

Brocade FCX624S

24Gig-E and 4 SFP+

8Q

2 MB

1.04 MB to 1 port

Juniper Ex4500 / Ex4550

40 SFP+ plus 8 SFP+

8Q

4 MB per ASIC

230 KBytes

Brocade ICX6610-24

24Gig-E w 8 SFP+

8Q

4 MB

1 MB to 1 port

HP 3800

24Gig-E and 4 10Gb/s

8Q or 4Q or 2 Q

0.23 MB

HP 2920-24

24 tw-pr Gig-E and 4 optional 10Gb/s

8Q

11.25 MB

4.5 MB shared

6.75 MB shared

HP 2824

20 tw-pr Gig-E and 4 SFP

4Q

0.512 MB shared

0.512 MB shared

HP A5800-24G

24Gig-E and 4 10Gb/s

8Q

4 MB

4 MB

HP E6600-24G-4XG

24Gig-E w 2 10Gb/s

8Q

18 MB for GE

18 MB

Arista 7124SX

24 x SFP+

8Q

2 MB/sw-chip

shared

1.238 + 0.02 MB

Arista 7148SX

48 SFP+

8Q

2 MB/sw-chip, 8 MB total

1.238 + 0.02 MB

Arista DCS-7150S-24

24 SFP+

8Q

7.5 MB

Arista DSC-7150S-52

52 SFP+

8Q

7.5 MB

Arista DCS-7150S-64

48 SFP+ and 4 QSFP+

8Q

7.5 MB

Dell 8024

24 SFP+

2Q

2 MB

Dell 6248

48 Gig-E, 4 x SFP+

8Q

0.75 MByte

98 KB per port

Dell 7024

24 Gig-E, 4 x SFP+

8Q

4 MB

4 MB

IBM BNT G8052

48 GE + 4 SFP+

8Q

4 MB/switch

4 MB

Nortel 5520-48T ver 1-3

48 GE + 4 SFP shared

8Q fixed

786 KB per 12-port

131 KB w 8 Queues

Nortel 5520-48T ver 4-5

48 GE + 4 SFP shared

1 to 8Q

786 KB per 12-port

786 KB w 1 Queue

Catalyst 3750G-48TS, 2960G

12 ASICs w/ 4 GE ports ea

8Q

1P3Q3T

576KB per ASIC

192KB per ASIC

384 KB per ASIC

Catalyst 2960S

Single ASIC: 48 +2 10Gb/s

8Q

1P3Q3T

2 MByte

2 MByte

Catalyst 3750E, 3560E, 3750X & 3560X

ASIC support 24 GE ports or 2 x 10G

2Q

1P3Q3T

2750KB per ASIC

750KB per ASIC

2 MB per ASIC

Catalyst 2960-X

ASIC support 48 GE ports AND uplink and stack

4Q

4 MB per ASIC

Catalyst 4948E

48 GigE + 4 SFP+

4

17.5 MB

Max 16 MB to 1 port

Cisco Ctalyst 4510R+E

Chassis w 8 interface slots -- 12 port SFP+ line card

8

1P7Q1T

32 MB on Supervisor

Max 14 MB to 1 port

Cisco Catalyst WS-C4500X-32SFP+

1 RU w 32 SFP+ ports and module for 8 more

8

1P7Q1T

32 MB

see note above

Cisco Nexus 3548 and 3548X

48 SFP+

4

18 MB

5.8 MB

Large queue 1RU switches

Force10 S60

48 Gig-E + 4 SFP+

4Q

1250 MB

enough

Arista 7048

48 Gig-E + 4 SFP+

8Q

768 MB

16 MB/port?

GOBBS

Corsa DP2100

32 1/10 G SFP+

8Q

6 GB

see note

Corsa DP2200

32 1/10 G SFP+ and 2 QSFP28 100G

8Q

6 GB

see note

Corsa DP2400

32 1/10 G SFP+ and 2 QSFP28 100G + stack

8Q

6 GB

see note

Corsa DP6430

24 SFP+ and 2 CFP/2 100G

8Q

20 GB

see note

Corsa DP6440

48 SFP+ and 4 CFP/2 100G

8Q

20 GB

see note

Virtual Output Port queuing

Brocade MLX

2-port 100 Gb/s line card

8Q

3 GB

256 MB/port-queue

VoQ

Brocade MLX

8-port 10 Gb/s line card

8Q

3 GB

256 MB/port-queue

VoQ

Brocade MLX

24-port 1 Gb/s line card

8Q

1 GB

64 MB/port-queue

VoQ

Extreme BlackDiamond X8

96-port SFP+ line card

48-port QSFP+ line card

4-port CFP2 100 Gb/s line card

8Q

9 MB per 24 10-Gb/s ports

9 MB per 6 40-Gb/s ports

36 MB per fabric module

Who knows??

Cisco Nexus 5010

26 SFP+

8

1 (I think)

480 KB per port

480 KB

VoQ

Cisco Nexus 5548P

32 fixed SFP+ and 16-port expansion module

8 Unicast 8 Multi

1 (I think)

640 KB per port

640 KB

VoQ

Cisco Nexus 5672UP

48 fixed SFP+ and 6 QSFP+

8 Unicast 8 Multi

1 (I think)

25 MB per 12-port 10G ASIC

14 MB shared per ASIC

3 MB Unicast + 6 MB Multicast

Cisco Nexus 6001

48 fixed SFP+ and 4 QSFP+

8 Unicast 8 Multi

1 (I think)

25 MB per 12-port 10G ASIC

14 MB shared per ASIC

3 MB Unicast + 6 MB Multicast

Cisco ASR-9000

Chassis solution. 1-6 ports per ASIC

ASICs have 0.5 to 3.3 GB/port

VoQ

Juniper QFX10002-36

QSFP: 12 x 100 Gb/s OR 36 x 40 Gb/s

8Q

4 GByte per ASIC

VoQ 100 mS per port

Nexus 7000/7700

Cisco Nexus 7000 (M1 series)

48-port Tw-Pr GE

2q4t

1p3q4t

7.56 MB per port

6.15 MB per port

Cisco Nexus 7000 (F3 Series)

6-port 100GE CPAK

4q

4q

72 MB shared

VoQ

Cisco Nexus 7000 (F2 series)

48 SFP+ across 12 ASICs

4q1t

1p3q1t

72 MB shared

VoQ

Cisco Nexus 7000 (F3 series)

12 QSFP+ across 6 ASICs

4q1t

1p3q1t

72 MB shared

VoQ

Cisco Nexus 7000 (M1 series)

32-port 10GE shared 4-port groups SFP+

8q2t

1p7q4t

65 MB per group

80 MB per group

Cisco Nexus 7000 (M1 series)

8-port 10GE X2

8q2t

1p7q4t

92 MB

80 MB

Cisco Nexus 7000 (M2 series)

2-port 100GE CFP2

8q2t

1p7q4t

62.46 MB

31.23 MB

Cisco Nexus 7000 (M2 series)

24-port 10GE SFP+

8q2t

1p7q4t

5.21 MB

5.21 MB

Cisco Nexus 7700 (F3 Series)

12-port 100GE CPAK across 12 ASICs

4q

4q

144 MB shared

VoQ

Cisco Nexus 7700 (F3 Series)

24-port 40GE QSFP+ across 12 ASICs

4q

4q

144 MB shared

VoQ

Cisco Nexus 7700 (F3 Series)

48-port 10GE SFP+ across 6 ASICs

4q

4q

144 MB shared

VoQ

Cisco Catalyst 6500 gets its own table

Comments, suggestions, corrections to warner@ucsc.edu

Opinions herein are solely those of jim warner. The University has no opinions, and if they did, these would not be them.