( turul16 | 2021. 02. 04., cs – 08:39 )

QSFP+/ QDR connectx 2/3 pcie gen2/3:

Ez meg nem hasznal FEC -et, a FEC noveli a latencyt.
Hany meteres a DAC kabeled ? FEC mar kotelezo -e rajta ?

2m jofele kabelnel FEC nem kell.
Egyesek allitjak, hogy 3m -nel is ki lehet kapcsolni:
https://blog.mellanox.com/2018/04/mellanox-ofc-2018-mellanox-live-demo-…
ill. hogy 2x250ns lehet az RS-FEC latency.
Mellanox cuccok tipikusan tudnak mas FEC -et pl. Fire code ami kicsit gyorsabb.
QSFP28 -nal 3m no-fec (26AWG)  -et tobben is allitjak hogy OK.

#ib_write_lat

---------------------------------------------------------------------------------------
 #bytes #iterations    t_min[usec]    t_max[usec]  t_typical[usec]    t_avg[usec]    t_stdev[usec]   99% percentile[usec]   99.9% percentile[usec] 
 2       1000          0.81           5.94         0.88     	       0.91        	0.16   		1.10    		5.94   
 4       1000          0.81           6.51         0.88     	       0.90        	0.17   		1.11    		6.51   
 8       1000          0.83           7.21         0.88     	       0.91        	0.20   		1.10    		7.21   
 16      1000          0.82           8.42         0.89     	       0.91        	0.18   		1.14    		8.42   
 32      1000          0.85           6.67         0.94     	       0.96        	0.21   		1.15    		6.67   
 64      1000          0.90           7.93         0.97     	       0.99        	0.24   		1.18    		7.93   
 128     1000          1.03           8.39         1.09     	       1.11        	0.25   		1.30    		8.39   
 256     1000          1.96           8.65         2.03     	       2.08        	0.26   		2.35    		8.65   
 512     1000          2.19           7.94         2.28     	       2.33        	0.31   		2.84    		7.94   
 1024    1000          2.58           8.75         2.67     	       2.71        	0.30   		3.67    		8.75   
 2048    1000          3.40           8.41         3.49     	       3.54        	0.29   		5.37    		8.41   
 4096    1000          4.04           10.03        4.17     	       4.25        	0.37   		5.94    		10.03  
 8192    1000          5.13           10.09        5.46     	       5.55        	0.30   		6.84    		10.09  
 16384   1000          7.58           14.16        7.91     	       7.99        	0.49   		11.23   		14.16  
 32768   1000          12.57          18.12        12.96    	       13.00       	0.38   		15.29   		18.12  
 65536   1000          22.87          32.33        23.05    	       23.09       	0.20   		23.63   		32.33  
 131072  1000          43.04          48.95        43.28    	       43.45       	0.66   		47.03   		48.95  
 262144  1000          83.42          87.29        83.64    	       83.69       	0.26   		84.20   		87.29  
 524288  1000          164.14         169.87       164.45   	       164.49      	0.27   		165.15  		169.87 
 1048576 1000          325.65         329.35       326.03   	       326.08      	0.30   		327.62  		329.35 
 2097152 1000          648.70         656.20       649.54   	       649.67      	0.72   		653.58  		656.20 
 4194304 1000          1294.62        1304.04      1296.07  	       1296.17     	0.71   		1298.89 		1304.04
 8388608 1000          2613.64        2642.17      2631.10  	       2631.24     	1.44   		2636.03 		2642.17




# ib_read_lat
 

---------------------------------------------------------------------------------------
 #bytes #iterations    t_min[usec]    t_max[usec]  t_typical[usec]    t_avg[usec]    t_stdev[usec]   99% percentile[usec]   99.9% percentile[usec] 
 2       1000          1.70           5.88         1.75     	       1.79        	0.16   		2.23    		5.88   
 4       1000          1.71           5.95         1.76     	       1.81        	0.14   		2.24    		5.95   
 8       1000          1.72           4.62         1.78     	       1.81        	0.10   		2.23    		4.62   
 16      1000          1.70           7.95         1.73     	       1.77        	0.12   		2.19    		7.95   
 32      1000          1.71           5.31         1.74     	       1.78        	0.12   		2.15    		5.31   
 64      1000          1.67           7.11         1.76     	       1.80        	0.12   		2.19    		7.11   
 128     1000          1.78           9.94         1.82     	       1.86        	0.13   		2.34    		9.94   
 256     1000          1.88           6.63         1.93     	       1.97        	0.11   		2.37    		6.63   
 512     1000          2.13           6.20         2.18     	       2.23        	0.14   		2.64    		6.20   
 1024    1000          2.53           9.66         2.57     	       2.62        	0.22   		3.01    		9.66   
 2048    1000          3.33           10.38        3.38     	       3.42        	0.18   		3.86    		10.38  
 4096    1000          3.94           11.33        4.01     	       4.05        	0.33   		4.49    		11.33  
 8192    1000          5.16           12.39        5.23     	       5.33        	0.35   		6.05    		12.39  
 16384   1000          7.43           14.33        7.68     	       7.81        	0.25   		8.56    		14.33  
 32768   1000          12.30          18.21        12.79    	       12.74       	0.37   		13.57   		18.21  
 65536   1000          22.47          27.71        22.55    	       22.61       	0.17   		23.06   		27.71  
 131072  1000          42.44          50.41        42.58    	       42.67       	0.40   		43.32   		50.41  
 262144  1000          82.30          88.90        82.45    	       82.52       	0.37   		83.19   		88.90  
 524288  1000          162.13         168.88       162.28   	       162.36      	0.39   		163.20  		168.88 
 1048576 1000          321.65         328.88       321.93   	       321.99      	0.38   		322.74  		328.88 
 2097152 1000          640.69         646.62       641.29   	       641.33      	0.36   		643.05  		646.62 
 4194304 1000          1278.99        1307.72      1279.90  	       1279.99     	0.92   		1282.17 		1307.72
 8388608 1000          2555.37        2567.06      2557.46  	       2557.62     	0.95   		2560.52 		2567.06


A valasz idok jobbnak tunnek a kisebb csomagoknal, de nagyobb csomagoknal a bandwith szamit.

ib_read_bw

---------------------------------------------------------------------------------------
 #bytes     #iterations    BW peak[MB/sec]    BW average[MB/sec]   MsgRate[Mpps]
 2          1000             6.04               5.91              3.099655
 4          1000             12.39              12.23             3.206630
 8          1000             24.56              24.11             3.160711
 16         1000             49.51              48.64             3.187653
 32         1000             97.76              95.79             3.138737
 64         1000             208.36             194.84            3.192182
 128        1000             379.81             375.05            3.072390
 256        1000             776.82             766.43            3.139281
 512        1000             1529.26            1500.69           3.073417
 1024       1000             2907.27            2857.69           2.926272
 2048       1000             3099.51            3092.07           1.583142
 4096       1000             3118.43            3116.47           0.797816
 8192       1000             3124.32            3122.52           0.399682
 16384      1000             3125.64            3125.57           0.200036
 32768      1000             3131.76            3131.70           0.100214
 65536      1000             3131.81            3131.81           0.050109
 131072     1000             3132.74            3132.74           0.025062
 262144     1000             3132.77            3132.66           0.012531
 524288     1000             3132.43            3132.43           0.006265
 1048576    1000             3130.04            3130.01           0.003130
 2097152    1000             3130.06            3129.72           0.001565
 4194304    1000             3133.08            3132.71           0.000783
 8388608    1000             3132.58            3132.58           0.000392


ib_write_bw

---------------------------------------------------------------------------------------
 #bytes     #iterations    BW peak[MB/sec]    BW average[MB/sec]   MsgRate[Mpps]
 2          5000             6.44               6.39   		   3.350616
 4          5000             12.84              12.75  		   3.341600
 8          5000             25.91              25.81  		   3.382843
 16         5000             52.09              51.45  		   3.371902
 32         5000             103.72             102.88 		   3.371066
 64         5000             207.24             204.10 		   3.343947
 128        5000             412.64             408.28 		   3.344640
 256        5000             831.96             823.11 		   3.371450
 512        5000             1627.38            1610.81		   3.298936
 1024       5000             3048.47            3041.68		   3.114685
 2048       5000             3059.80            3057.74		   1.565565
 4096       5000             3062.97            3062.34		   0.783960
 8192       5000             3064.21            3064.10		   0.392205
 16384      5000             3064.67            3064.62		   0.196136
 32768      5000             3064.99            3064.96		   0.098079
 65536      5000             3065.13            3065.09		   0.049042
 131072     5000             3065.12            3065.11		   0.024521
 262144     5000             3065.24            3065.20		   0.012261
 524288     5000             3065.25            3065.22		   0.006130
 1048576    5000             3065.12            3064.82		   0.003065
 2097152    5000             3065.22            3065.21		   0.001533
 4194304    5000             3065.28            3065.24		   0.000766
 8388608    5000             3065.25            3065.25		   0.000383


hometech from ebay ;-)
gep1:
Mellanox Technologies MT25408A0-FCC-QI ConnectX, Dual Port 40Gb/s InfiniBand / 10GigE Adapter IC with PCIe 2.0 x8 5.0GT/s In... (rev b0)
Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz

gep2:
Mellanox Technologies MT27500 Family [ConnectX-3]
AMD Ryzen 9 3900X 12-Core Processor

NVMeoF, nfs+rdma kozel az itt lathato BW -el megy, meg az osregi Q9300 -as procival is.

Dual port kartyak, 3 gep directbe (DAC).

(A test allatt cpu intiseve boinc/rosetta futott parhuzamosan)