UDP performance problems

Hi guys!

I have a problem. I'm testing a bunch of software packages, all of them
have to receive UDP (multicast) packets, and all of them runs on a Linux
2.6 kernel.

The packets are injected in a LAN by a Cisco router at a very high
bitrate (10 Mbit/s, 50 Mbit/s, ... up to 100). I can monitor the packet
flow with tcpdump and ethereal, and those packets are actually present
on the LAN.

The problem, present independently in each software, is that the
applications can't receive that huge amount of packets. Let me
explain... If the bitrate is 20 Mbit/s, the applications successfully
process the first 5-10 MB, then hang (it doesn't mean that the
applications crash, they simple behave like if no more packets are sent
or received). The kernel receives UDP packet, I'm sure since I can see
the flow with tcpdump, but the user software doesn't.

If I transmit the data at max 2.5 Mbit/s, I have no problems.

Can you help me?

PC are powerful enough to process an FTP file transfer running at 95
Mbit/s. UDP send and receive buffers have been already enlarged (up to 2
MB from few KB) without obtaining any result or modification of this
strange behavior.

Thanks.

Ciao
Stefano

"Stefano Pettini" <(E-Mail Removed)> wrote in message
news:_dNUd.56006$(E-Mail Removed)...

> The problem, present independently in each software, is that the
> applications can't receive that huge amount of packets. Let me explain...
> If the bitrate is 20 Mbit/s, the applications successfully process the
> first 5-10 MB, then hang (it doesn't mean that the applications crash,
> they simple behave like if no more packets are sent or received). The
> kernel receives UDP packet, I'm sure since I can see the flow with
> tcpdump, but the user software doesn't.

What is the application doing when it hangs? What does 'strace' show? Or
a 'where' if you attach 'gdb' to it?

DS

Stefano Pettini <(E-Mail Removed)> writes:

> The problem, present independently in each software, is that the
> applications can't receive that huge amount of packets. Let me
> explain... If the bitrate is 20 Mbit/s, the applications successfully
> process the first 5-10 MB, then hang (it doesn't mean that the
> applications crash, they simple behave like if no more packets are
> sent or received). The kernel receives UDP packet, I'm sure since I
> can see the flow with tcpdump, but the user software doesn't.

You have a bug in your client code; we can't solve the problem without
seeing the code.

--KW 8-)
--
Keith Wansbrough <(E-Mail Removed)>
http://www.cl.cam.ac.uk/users/kw217/
University of Cambridge Computer Laboratory.

Stefano Pettini wrote:
> Hi guys!
>
> I have a problem. I'm testing a bunch of software packages, all of them
> have to receive UDP (multicast) packets, and all of them runs on a Linux
> 2.6 kernel.
>
> The packets are injected in a LAN by a Cisco router at a very high
> bitrate (10 Mbit/s, 50 Mbit/s, ... up to 100). I can monitor the packet
> flow with tcpdump and ethereal, and those packets are actually present
> on the LAN.
>
> The problem, present independently in each software, is that the
> applications can't receive that huge amount of packets. Let me
> explain... If the bitrate is 20 Mbit/s, the applications successfully
> process the first 5-10 MB, then hang (it doesn't mean that the
> applications crash, they simple behave like if no more packets are sent
> or received). The kernel receives UDP packet, I'm sure since I can see
> the flow with tcpdump, but the user software doesn't.
>
> If I transmit the data at max 2.5 Mbit/s, I have no problems.
>
> Can you help me?

You need to find the bug in your client code.

That is as helpful as I can be without more details on your code.

> PC are powerful enough to process an FTP file transfer running at 95
> Mbit/s. UDP send and receive buffers have been already enlarged (up to 2
> MB from few KB) without obtaining any result or modification of this
> strange behavior.
>
> Thanks.
>
> Ciao
> Stefano

--
Phil Frisbie, Jr.
Hawk Software
http://www.hawksoft.com

Hi Stefano:


Sounds somewhat familiar to me.

Some possible roads to travel down:

(1). For some reason, maybe the kernel is shutting down half
of the socket, i.e., the listening half. Don't know what
could be causing it offhand, but you try using gdb to probe.

(2). Check to see your udp stats via ifconfig to see if the
udp packets are still being gathered from the interface, but
perhaps not being delivered to the application level. Again,
I don't know why, but check..

(3). You mentioned that these were <multicast> packets, right?
If so, I once had a very, very similar problem to what you're
describing. I had a situation where the packets would be
received for awhile, but then all of a sudden it would stop.
It turned out that the ethernet driver (for a National
Semiconductor ethernet chip), would have something like a RX
FIFO Overflow error interrupt, and the controller would be reset
- OK, no big deal, that happens. Well, one of the things that
the reset would <not> do, is to re-insert the multicast group
addresses within the hash table, - i.e., resubscribe to the
multicast groups - thus, it was never getting the packets
until a full reset was done.

Well, check on those items if you want...

Hope it helps.

g.

Hi Stefano & others:


I have seen similar problems with udp datagrams on Linux. I found a
test program that I have run
(http://home.earthlink.net/~jrhay/src/udptest/) that will show
statistics for upd datagrams. I have run it on a few different machines
with the results below. These machines are connected via crossover
cable on the interfaces used for this test (the test is *not* run over
a network). I would be very interested in resolving this issue and
would be willing to put some effort into more testing. I realize that
udp can be prone to loss, but does it still hold true if you are on a
crossover, or using the loopback address?

The udptest.pl script at the bottom of the page is how the application
was run from the client side. This will let you know the options used
for each test below. There could be a problem with the udptest.c code,
it is not mine, and I have not looked it over.

Options for the code started at:
<remote ip> 100 4096 1000
<remote ip> 100 5120 1000
<remote ip> 100 6144 1000
....
<remote ip> 100 64512 1000 #biggest is 65507 < 64512 + 1024
<remote ip> 1000 4096 1000
<remote ip> 1000 5120 1000
....
<remote ip> 1000 64512 1000
<remote ip> 10000 4096 1000
etc

Here is some output statistics from the server:
Sender: IBM x336 (Dual CPU, onboard broadcom bcm57xx (forced to 100mb/s
full duplex)) running RHEL ES 2.1 (Pensacola) kernel 2.4.9-e.24
Receiver: IBM x336 (Dual CPU, onboard broadcom bcm57xx (forced to
100mb/s full duplex)) running RHEL ES 2.1 (Pensacola) kernel 2.4.9-e.24
# Datagrams Dropped Duplicated Bytes Time (s) Efficiency Data bps Total
bps
100 0 0 409600 0.99 100.00% 3320032 3313561
100 0 0 512000 0.99 100.00% 4148364 4141892
100 0 0 614400 0.99 100.00% 4976596 4970125
100 0 0 716800 0.99 100.00% 5804804 5798332
100 0 0 819200 0.99 100.00% 6633137 6626666
100 0 0 921600 0.99 100.00% 7461485 7455014
100 0 0 1024000 0.99 100.00% 8289963 8283491
100 0 0 1126400 0.99 100.00% 9117842 9111370
100 0 0 1228800 0.99 100.00% 9946681 9940209
100 0 0 1331200 0.99 100.00% 10774988 10768517
100 0 0 1433600 0.99 100.00% 11603570 11597099
100 0 0 1536000 0.99 100.00% 12431432 12424960
100 0 0 1638400 0.99 100.00% 13259803 13253331
100 0 0 1740800 0.99 100.00% 14088307 14081835
100 0 0 1843200 0.99 100.00% 14916921 14910450
100 0 0 1945600 0.99 100.00% 15744532 15738060
100 0 0 2048000 0.99 100.00% 16573320 16566848
100 0 0 2150400 0.99 100.00% 17401697 17395226
100 0 0 2252800 0.99 100.00% 18229691 18223220
100 0 0 2355200 0.99 100.00% 19058347 19051876
100 0 0 2457600 0.99 100.00% 19886911 19880439
100 0 0 2560000 0.99 100.00% 20715074 20708602
100 0 0 2662400 0.99 100.00% 21543200 21536729
100 0 0 2764800 0.99 100.00% 22371807 22365336
100 0 0 2867200 1.00 100.00% 22967933 22961526
100 0 0 2969600 1.00 100.00% 23792679 23786271
100 0 0 3072000 1.00 100.00% 24612082 24605674
100 0 0 3174400 1.00 100.00% 25432322 25425915
100 0 0 3276800 1.00 100.00% 26252644 26246237
99 1 0 3345408 1.00 99.00% 26802648 26796304
100 0 0 3481600 1.00 100.00% 27892950 27886543
96 4 0 3440640 1.00 96.00% 27563927 27557776
100 0 0 3686400 1.00 100.00% 29531680 29525272
100 0 0 3788800 1.00 100.00% 30349760 30343353
100 0 0 3891200 1.00 100.00% 31168259 31161853
100 0 0 3993600 1.00 100.00% 31988084 31981677
100 0 0 4096000 1.00 100.00% 32808127 32801720
97 3 0 4072448 1.00 97.00% 32620631 32614416
100 0 0 4300800 1.98 100.00% 17388870 17385636
100 0 0 4403200 0.99 100.00% 35624871 35618400
100 0 0 4505600 0.99 100.00% 36453464 36446993
99 1 0 4561920 0.99 99.00% 36908688 36902281
100 0 0 4710400 0.99 100.00% 38110723 38104252
100 0 0 4812800 0.99 100.00% 38938053 38931582
99 1 0 4866048 0.99 99.00% 39369278 39362871
100 0 0 5017600 0.99 100.00% 40595045 40588573
100 0 0 5120000 0.99 100.00% 41424681 41418210
100 0 0 5222400 0.99 100.00% 42251678 42245207
100 0 0 5324800 0.99 100.00% 43079972 43073501
96 4 0 5210112 0.99 96.00% 42152189 42145977
1000 0 0 4096000 9.99 100.00% 3286749 3280342
997 3 0 5104640 9.99 99.70% 4094503 4088116
999 1 0 6137856 9.99 99.90% 4921984 4915583
999 1 0 7160832 9.99 99.90% 5741243 5734842
997 3 0 8167424 9.99 99.70% 6547376 6540988
999 1 0 9206784 9.99 99.90% 7379770 7373369
994 6 0 10178560 9.99 99.40% 8158014 8151645
996 4 0 11218944 9.99 99.60% 8991204 8984823
999 1 0 12275712 9.99 99.90% 9837556 9831156
997 3 0 13272064 9.99 99.70% 10635449 10629061
995 5 0 14264320 9.95 99.50% 11476116 11469715
997 3 0 15313920 9.99 99.70% 12270742 12264355
993 7 0 16269312 9.99 99.30% 13035874 13029512
1000 0 0 17408000 9.99 100.00% 13947839 13941432
994 6 0 18321408 9.99 99.40% 14679311 14672942
993 7 0 19319808 9.99 99.30% 15478993 15472631
999 1 0 20459520 9.99 99.90% 16391690 16385289
995 5 0 21396480 9.99 99.50% 17141995 17135620
998 2 0 22482944 9.99 99.80% 18012194 18005800
997 3 0 23481344 9.99 99.70% 18811703 18805315
990 10 0 24330240 9.99 99.00% 19491587 19485244
999 1 0 25574400 9.99 99.90% 20488049 20481648
990 10 0 26357760 9.99 99.00% 21115321 21108978
996 4 0 27537408 9.99 99.60% 22060082 22053700
1000 0 0 28672000 9.99 100.00% 22968765 22962358
991 9 0 29428736 9.99 99.10% 23574660 23568311
999 1 0 30689280 9.99 99.90% 24584376 24577976
998 2 0 31680512 9.99 99.80% 25378165 25371771
996 4 0 32636928 10.00 99.60% 26117962 26111587
981 19 0 33149952 10.00 98.10% 26528296 26522017
995 5 0 34641920 10.00 99.50% 27722083 27715714
992 8 0 35553280 11.46 99.20% 24826198 24820657
999 1 0 36827136 9.99 99.90% 29499992 29493591
996 4 0 37736448 9.99 99.60% 30228128 30221747
989 11 0 38483968 9.99 98.90% 30826717 30820380
1000 0 0 39936000 9.99 100.00% 31989707 31983300
992 8 0 40632320 10.03 99.20% 32417449 32411118
997 3 0 41858048 9.99 99.70% 33528957 33522569
979 21 0 42104832 9.99 97.90% 33726529 33720257
998 2 0 43943936 9.99 99.80% 35199520 35193126
989 11 0 44560384 9.99 98.90% 35693032 35686695
997 3 0 45941760 9.99 99.70% 36799518 36793130
999 1 0 47056896 9.99 99.90% 37692551 37686150
989 11 0 47598592 9.99 98.90% 38126334 38119997
997 3 0 49004544 9.99 99.70% 39252310 39245923
987 13 0 49523712 9.99 98.70% 39668100 39661777
993 7 0 50841600 9.99 99.30% 40723450 40717088
992 8 0 51806208 9.99 99.20% 41495907 41489551
996 4 0 53035008 9.99 99.60% 42480340 42473959
994 6 0 53946368 9.99 99.40% 43210106 43203737
9982 18 0 40886272 100.26 99.82% 3268732 3262360
9989 11 0 51143680 99.99 99.89% 4098221 4091827
9979 21 0 61310976 99.94 99.79% 4914123 4907732
9976 24 0 71507968 99.99 99.76% 5727491 5721106
9990 10 0 81838080 99.99 99.90% 6553975 6547581
9986 14 0 92030976 100.56 99.86% 7327699 7321344
9988 12 0 102277120 99.99 99.88% 8189232 8182839
9973 27 0 112335872 99.99 99.73% 8993987 8987604
9970 30 0 122511360 99.99 99.70% 9808092 9801710
9984 16 0 132907008 100.63 99.84% 10572152 10565802
9954 46 0 142700544 99.99 99.54% 11423348 11416977
9988 12 0 153415680 99.95 99.88% 12285566 12279170
9970 30 0 163348480 99.99 99.70% 13075325 13068943
9973 27 0 173609984 99.99 99.73% 13896318 13889935
9974 26 0 183840768 100.87 99.74% 14586473 14580145
9966 34 0 193898496 99.99 99.66% 15519523 15513145
9971 29 0 204206080 99.99 99.71% 16344204 16337822
9968 32 0 214351872 99.99 99.68% 17155931 17149551
9983 17 0 224897024 99.99 99.83% 17999625 17993236
9968 32 0 234766336 100.97 99.68% 18606853 18600535
9979 21 0 245243904 99.99 99.79% 19627503 19621116
9957 43 0 254899200 99.99 99.57% 20399976 20393603
9964 36 0 265281536 100.04 99.64% 21220028 21213653
9959 41 0 275346432 101.17 99.59% 21778872 21772572
9964 36 0 285687808 99.99 99.64% 22863269 22856891
9975 25 0 296217600 99.99 99.75% 23705729 23699344
9974 26 0 306401280 99.99 99.74% 24520490 24514106
9956 44 0 316043264 99.99 99.56% 25291898 25285526
9941 59 0 325746688 101.32 99.41% 25726037 25719758
9954 46 0 336365568 99.99 99.54% 26917819 26911448
9968 32 0 347045888 99.99 99.68% 27772320 27765940
9966 34 0 357181440 101.53 99.66% 28149127 28142845
9944 56 0 366575616 101.50 99.44% 28898970 28892700
9971 29 0 377781248 99.99 99.71% 30231347 30224965
9970 30 0 387952640 99.99 99.70% 31045128 31038747
9974 26 0 398321664 99.99 99.74% 31874715 31868331
9952 48 0 407633920 99.99 99.52% 32619758 32613388
9942 58 0 417404928 101.68 99.42% 32846320 32840063
9951 49 0 427972608 99.99 99.51% 34246988 34240619
9943 57 0 437810176 99.99 99.43% 35034041 35027677
9965 35 0 448983040 100.04 99.65% 35909996 35903621
9948 52 0 458403840 100.87 99.48% 36361657 36355346
9943 57 0 468355072 99.99 99.43% 37477842 37471478
9947 53 0 478729216 99.99 99.47% 38307836 38301470
9960 40 0 489553920 99.99 99.60% 39173885 39167510
9906 94 0 497043456 99.95 99.06% 39788978 39782635
9933 67 0 508569600 102.01 99.33% 39889398 39883166
9925 75 0 518323200 99.99 99.25% 41475602 41469249
9925 75 0 528486400 99.99 99.25% 42288724 42282372
9927 73 0 538758144 100.04 99.27% 43088977 43082626
99848 152 0 408977408 1000.90 99.85% 3275249 3268864
99844 156 0 511201280 1000.66 99.84% 4093307 4086921
99807 193 0 613214208 1000.78 99.81% 4908263 4901880
99811 189 0 715445248 1000.84 99.81% 5725152 5718769
99841 159 0 817897472 1000.98 99.84% 6543170 6536786
99789 211 0 919655424 1000.96 99.79% 7356538 7350158
99782 218 0 1021767680 1001.13 99.78% 8171262 8164883
99773 227 0 1123843072 1001.18 99.77% 8986561 8980183
99779 221 0 1226084352 1001.20 99.78% 9803257 9796879
99748 252 0 1327845376 1001.26 99.75% 10615792 10609416
99794 206 0 1430646784 1001.37 99.79% 11435871 11429493
99739 261 0 1531991040 1001.61 99.74% 12242551 12236178
99680 320 0 1633157120 1002.46 99.68% 13039533 13033169
99650 350 0 1734707200 1001.59 99.65% 13861994 13855626
99736 264 0 1838333952 1001.67 99.74% 14688583 14682210
99690 310 0 1939568640 1001.78 99.69% 15495284 15488916
99634 366 0 2040504320 1001.88 99.63% 16299734 16293370
99652 348 0 2142916608 1001.94 99.65% 17116537 17110172
99658 342 0 -2049871872 1003.09 99.66% 17911792 17905434
99579 421 0 -1949682688 1003.09 99.58% 18710794 18704441
99624 376 0 -1846607872 1003.29 99.62% 19529038 19522683
99665 335 0 -1743543296 1002.20 99.67% 20372909 20366544
99618 382 0 -1642737664 1002.20 99.62% 21177621 21171260
99601 399 0 -1541198848 1002.31 99.60% 21985777 21979417
99541 459 0 -1440927744 1002.49 99.54% 22781912 22775557
99526 474 0 -1339443200 1003.79 99.53% 23561169 23554823
99531 469 0 -1237374976 1002.50 99.53% 24406188 24399834
99547 453 0 -1134947328 1002.64 99.55% 25219846 25213491
99523 477 0 -1033797632 1002.82 99.52% 26022290 26015939
99543 457 0 -931210240 1002.72 99.54% 26843463 26837110
99430 570 0 -833212416 1002.84 99.43% 27621843 27615497
99483 517 0 -729496576 1002.99 99.48% 28445024 28438676
99371 629 0 -631754752 1001.52 99.37% 29267454 29261104
99505 495 0 -524921856 1003.10 99.50% 30073442 30067094
99439 561 0 -425596928 1004.76 99.44% 30814672 30808338
99442 558 0 -323651584 1001.66 99.44% 31724225 31717871
99526 474 0 -218382336 1003.34 99.53% 32510591 32504242
99490 510 0 -117979136 1003.43 99.49% 33307889 33301543
99416 584 0 -19283968 1003.46 99.42% 34093726 34087386
99483 517 0 85468160 1005.37 99.48% 686426 680093
99398 602 0 183508992 1003.60 99.40% 1469139 1462800
99393 607 0 285062144 1001.80 99.39% 2282740 2276390
99352 648 0 384909312 1003.67 99.35% 3074344 3068009
99299 701 0 484094976 1003.87 99.30% 3864168 3857837
99324 676 0 587005952 1003.92 99.32% 4684052 4677720
99329 671 0 688964608 1004.09 99.33% 5495574 5489243
99332 668 0 790831104 1003.98 99.33% 6307888 6301555
99246 754 0 888055808 1004.19 99.25% 7081099 7074774
99341 659 0 994742272 1004.21 99.34% 7930890 7924559
99423 577 0 1100917760 1006.41 99.42% 8757567 8751245
998516 1484 0 -205045760 10006.64 99.85% 3276151 3269765

Sender: IBM x345 (Dual CPU (Hyperthreading disabled), add on compaq nic
(100mb/s) using e100 driver) running RHEL ES 2.1 (Pensacola) kernel
2.4.9-e.24
Receiver: IBM x345 (Dual CPU (Hyperthreading disabled), add on compaq
nic (100mb/s) using e100) running RHEL ES 2.1 (Pensacola) kernel
2.4.9-e.24
# Datagrams Dropped Duplicated Bytes Time (s) Efficiency Data bps Total
bps
100 0 0 409600 0.99 100.00% 3323733 3317254
100 0 0 512000 0.99 100.00% 4150286 4143811
100 0 0 614400 0.99 100.00% 4978691 4972216
100 0 0 716800 0.99 100.00% 5815677 5809193
100 0 0 819200 0.99 100.00% 6636083 6629608
100 0 0 921600 0.99 100.00% 7464897 7458423
100 0 0 1024000 1.16 100.00% 7076694 7071170
100 0 0 1126400 1.00 100.00% 9030948 9024538
100 0 0 1228800 1.00 100.00% 9851262 9844852
100 0 0 1331200 1.00 100.00% 10671912 10665502
100 0 0 1433600 1.00 100.00% 11492301 11485891
100 0 0 1536000 1.00 100.00% 12312376 12305967
100 0 0 1638400 1.00 100.00% 13132655 13126246
100 0 0 1740800 1.00 100.00% 13953535 13947125
100 0 0 1843200 1.00 100.00% 14773880 14767471
100 0 0 1945600 1.00 100.00% 15593842 15587433
100 0 0 2048000 0.99 100.00% 16524829 16518377
100 0 0 2150400 0.99 100.00% 17409584 17403110
100 0 0 2252800 0.99 100.00% 18237861 18231386
100 0 0 2355200 0.99 100.00% 19066618 19060144
100 0 0 2457600 0.99 100.00% 19895622 19889147
100 0 0 2560000 0.99 100.00% 20724336 20717862
100 0 0 2662400 0.99 100.00% 21553007 21546533
100 0 0 2764800 0.99 100.00% 22381833 22375359
100 0 0 2867200 0.99 100.00% 23217220 23210744
100 0 0 2969600 0.99 100.00% 24039097 24032622
100 0 0 3072000 0.99 100.00% 24868336 24861862
100 0 0 3174400 0.99 100.00% 25696753 25690279
100 0 0 3276800 0.99 100.00% 26525445 26518970
100 0 0 3379200 1.98 100.00% 13668529 13665294
100 0 0 3481600 1.09 100.00% 25593674 25587794
100 0 0 3584000 1.09 100.00% 26347248 26341368
100 0 0 3686400 1.00 100.00% 29541232 29534823
100 0 0 3788800 1.00 100.00% 30362465 30356056
100 0 0 3891200 1.00 100.00% 31182274 31175865
100 0 0 3993600 1.00 100.00% 32003397 31996987
100 0 0 4096000 1.00 100.00% 32823603 32817193
100 0 0 4198400 1.00 100.00% 33645380 33638970
100 0 0 4300800 1.00 100.00% 34464842 34458432
100 0 0 4403200 1.00 100.00% 35283373 35276963
100 0 0 4505600 1.00 100.00% 36104852 36098442
100 0 0 4608000 1.00 100.00% 36925012 36918603
100 0 0 4710400 1.00 100.00% 37743951 37737542
100 0 0 4812800 0.99 100.00% 38956409 38949935
100 0 0 4915200 0.99 100.00% 39785252 39778777
100 0 0 5017600 0.99 100.00% 40612867 40606393
100 0 0 5120000 0.99 100.00% 41442449 41435975
100 0 0 5222400 0.99 100.00% 42270613 42264139
100 0 0 5324800 0.99 100.00% 43099714 43093240
100 0 0 5427200 0.99 100.00% 43928430 43921956
100 0 0 5529600 0.99 100.00% 44756875 44750400
100 0 0 5632000 0.99 100.00% 45586877 45580403
100 0 0 5734400 0.99 100.00% 46413264 46406790
100 0 0 5836800 0.99 100.00% 47242960 47236486
100 0 0 5939200 1.00 100.00% 47591196 47584787
100 0 0 6041600 1.00 100.00% 48411721 48405311
100 0 0 6144000 1.00 100.00% 49231607 49225198
100 0 0 6246400 0.99 100.00% 50557494 50551020
100 0 0 6348800 1.00 100.00% 50872855 50866445
100 0 0 6451200 1.00 100.00% 51690900 51684491
1000 0 0 4096000 9.99 100.00% 3287130 3280722
1000 0 0 5120000 9.99 100.00% 4107290 4100883
1000 0 0 6144000 9.99 100.00% 4927469 4921061
1000 0 0 7168000 9.99 100.00% 5747659 5741251
1000 0 0 8192000 9.99 100.00% 6567841 6561433
1000 0 0 9216000 9.99 100.00% 7388016 7381608
1000 0 0 10240000 9.99 100.00% 8208209 8201801
1000 0 0 11264000 9.99 100.00% 9028379 9021971
1000 0 0 12288000 9.99 100.00% 9848561 9842153
1000 0 0 13312000 9.99 100.00% 10668749 10662341
1000 0 0 14336000 10.73 100.00% 10696475 10690510
1000 0 0 15360000 10.05 100.00% 12235576 12229207
1000 0 0 16384000 10.00 100.00% 13116137 13109735
1000 0 0 17408000 10.00 100.00% 13935523 13929122
1000 0 0 18432000 9.99 100.00% 14769635 14763227
1000 0 0 19456000 9.99 100.00% 15589813 15583405
1000 0 0 20480000 10.00 100.00% 16393552 16387151
1000 0 0 21504000 9.99 100.00% 17230235 17223827
1000 0 0 22528000 9.99 100.00% 18050374 18043966
1000 0 0 23552000 9.99 100.00% 18870509 18864101
1000 0 0 24576000 9.99 100.00% 19690689 19684281
1000 0 0 25600000 9.99 100.00% 20510904 20504497
1000 0 0 26624000 9.99 100.00% 21331029 21324621
1000 0 0 27648000 9.99 100.00% 22151273 22144865
1000 0 0 28672000 9.99 100.00% 22971428 22965020
1000 0 0 29696000 9.99 100.00% 23791655 23785247
1000 0 0 30720000 9.99 100.00% 24611774 24605367
1000 0 0 31744000 9.99 100.00% 25431894 25425487
1000 0 0 32768000 9.99 100.00% 26252200 26245793
1000 0 0 33792000 9.99 100.00% 27072357 27065949
1000 0 0 34816000 11.53 100.00% 24166534 24160983
1000 0 0 35840000 10.00 100.00% 28683836 28677434
1000 0 0 36864000 10.00 100.00% 29503150 29496748
1000 0 0 37888000 10.00 100.00% 30326762 30320360
1000 0 0 38912000 9.99 100.00% 31173068 31166660
1000 0 0 39936000 9.99 100.00% 31993182 31986775
1000 0 0 40960000 9.99 100.00% 32813402 32806994
1000 0 0 41984000 9.99 100.00% 33634257 33627849
1000 0 0 43008000 9.99 100.00% 34453838 34447430
1000 0 0 44032000 9.99 100.00% 35273867 35267459
1000 0 0 45056000 9.99 100.00% 36094195 36087788
1000 0 0 46080000 9.99 100.00% 36914310 36907902
1000 0 0 47104000 9.99 100.00% 37734425 37728017
1000 0 0 48128000 9.99 100.00% 38554672 38548265
1000 0 0 49152000 9.99 100.00% 39374734 39368326
1000 0 0 50176000 9.99 100.00% 40194887 40188480
1000 0 0 51200000 9.99 100.00% 41015101 41008694
1000 0 0 52224000 9.99 100.00% 41835338 41828930
1000 0 0 53248000 9.99 100.00% 42655462 42649054
1000 0 0 54272000 12.09 100.00% 35923173 35917879
1000 0 0 55296000 10.09 100.00% 43856891 43850547
1000 0 0 56320000 10.00 100.00% 45071094 45064693
1000 0 0 57344000 10.00 100.00% 45890259 45883858
1000 0 0 58368000 10.00 100.00% 46709595 46703194
1000 0 0 59392000 13.14 100.00% 36170040 36165169
1000 0 0 60416000 9.99 100.00% 48396632 48390225
1000 0 0 61440000 10.00 100.00% 49167771 49161370
1000 0 0 62464000 9.99 100.00% 50037119 50030712
1000 0 0 63488000 9.99 100.00% 50857137 50850729
1000 0 0 64512000 9.99 100.00% 51677357 51670949
10000 0 0 40960000 99.98 100.00% 3283741 3277339
10000 0 0 51200000 100.45 100.00% 4083879 4077508
10000 0 0 61440000 99.98 100.00% 4922410 4916009
10000 0 0 71680000 100.49 100.00% 5712604 5706236
10000 0 0 81920000 99.98 100.00% 6561075 6554674
10000 0 0 92160000 100.61 100.00% 7334199 7327838
10000 0 0 102400000 100.00 100.00% 8198104 8191704
10000 0 0 112640000 99.98 100.00% 9019078 9012677
10000 0 0 122880000 100.70 100.00% 9768077 9761722
10000 0 0 133120000 99.98 100.00% 10657749 10651348
10000 0 0 143360000 100.73 100.00% 11391637 11385284
10000 0 0 153600000 99.98 100.00% 12296418 12290017
10000 0 0 163840000 100.84 100.00% 13003906 12997560
10000 0 0 174080000 99.99 100.00% 13933694 13927294
10000 0 0 184320000 99.98 100.00% 14754419 14748018
10000 0 0 194560000 100.94 100.00% 15425658 15419318
10000 0 0 204800000 99.98 100.00% 16393093 16386692
10000 0 0 215040000 101.04 100.00% 17031869 17025535
10000 0 0 225280000 99.99 100.00% 18029952 18023551
10000 0 0 235520000 99.99 100.00% 18849207 18842806
10000 0 0 245760000 100.62 100.00% 19545329 19538968
10000 0 0 256000000 99.98 100.00% 20489769 20483368
10000 0 0 266240000 101.18 100.00% 21056398 21050073
10000 0 0 276480000 99.98 100.00% 22128427 22122026
10000 0 0 286720000 101.29 100.00% 22651011 22644693
10000 0 0 296960000 99.99 100.00% 23764727 23758326
10000 0 0 307200000 99.98 100.00% 24586443 24580042
10000 0 0 317440000 101.35 100.00% 25062380 25056066
10000 0 0 327680000 99.98 100.00% 26225104 26218703
10000 0 0 337920000 101.44 100.00% 26655234 26648925
10000 0 0 348160000 99.98 100.00% 27863779 27857378
10000 0 0 358400000 101.50 100.00% 28253606 28247300
10000 0 0 368640000 99.99 100.00% 29499500 29493100
10000 0 0 378880000 99.98 100.00% 30321775 30315374
10000 0 0 389120000 101.62 100.00% 30638575 30632277
10000 0 0 399360000 99.98 100.00% 31960454 31954053
10000 0 0 409600000 101.67 100.00% 32234948 32228653
10000 0 0 419840000 99.98 100.00% 33599118 33592717
10000 0 0 430080000 101.77 100.00% 33813124 33806835
10000 0 0 440320000 100.00 100.00% 35230755 35224355
10000 0 0 450560000 99.98 100.00% 36057118 36050717
10000 0 0 460800000 101.90 100.00% 36181689 36175409
10000 0 0 471040000 99.98 100.00% 37695792 37689391
10000 0 0 481280000 102.10 100.00% 37715449 37709181
10000 0 0 491520000 99.98 100.00% 39334455 39328054
10000 0 0 501760000 101.72 100.00% 39466976 39460685
10000 0 0 512000000 100.01 100.00% 40960840 40954441
10000 0 0 522240000 99.98 100.00% 41792432 41786031
10000 0 0 532480000 102.27 100.00% 41657676 41651418
9997 3 0 542557184 99.98 99.97% 43418087 43411688
10000 0 0 552960000 102.35 100.00% 43225891 43219638
10000 0 0 563200000 99.99 100.00% 45065299 45058898
10000 0 0 573440000 99.98 100.00% 45889123 45882722
10000 0 0 583680000 102.43 100.00% 45591348 45585100
10000 0 0 593920000 99.99 100.00% 47523039 47516638
10000 0 0 604160000 128.07 100.00% 37743716 37738719
10000 0 0 614400000 99.99 100.00% 49161554 49155154
10000 0 0 624640000 135.01 100.00% 37017205 37012465
10000 0 0 634880000 99.99 100.00% 50800056 50793656
10000 0 0 645120000 134.51 100.00% 38372837 38368079
100000 0 0 409600000 1001.56 100.00% 3278094 3271704
100000 0 0 512000000 1001.80 100.00% 4095038 4088650
100000 0 0 614400000 1001.95 100.00% 4912033 4905645
100000 0 0 716800000 1002.07 100.00% 5728954 5722567
100000 0 0 819200000 1002.23 100.00% 6545418 6539032
100000 0 0 921600000 1003.01 100.00% 7357071 7350690
100000 0 0 1024000000 1002.49 100.00% 8178055 8171670
100000 0 0 1126400000 1002.68 100.00% 8993519 8987136
100000 0 0 1228800000 1002.78 100.00% 9809552 9803170
100000 0 0 1331200000 1002.84 100.00% 10625848 10619466
100000 0 0 1433600000 1003.07 100.00% 11440107 11433726
100000 0 0 1536000000 1003.24 100.00% 12254723 12248343
100000 0 0 1638400000 1004.21 100.00% 13058654 13052280
100000 0 0 1740800000 1003.57 100.00% 13883271 13876893
100000 0 0 1843200000 1003.62 100.00% 14698826 14692449
100000 0 0 1945600000 1003.84 100.00% 15511674 15505299
99994 6 0 2047877120 1003.66 99.99% 16329690 16323314
99995 5 0 -2144674816 1003.47 100.00% 17149276 17142898
100000 0 0 -2042167296 1003.60 100.00% 17964175 17957798
100000 0 0 -1939767296 1003.63 100.00% 18779877 18773501
100000 0 0 -1837367296 1004.84 100.00% 19572520 19566151
100000 0 0 -1734967296 1003.91 100.00% 20406664 20400289
100000 0 0 -1632567296 1003.93 100.00% 21222251 21215876
99969 31 0 -1531024384 1004.15 99.97% 22026585 22020213
100000 0 0 -1427767296 1004.17 100.00% 22848779 22842405
100000 0 0 -1325367296 1004.41 100.00% 23658922 23652550
100000 0 0 -1222967296 1004.49 100.00% 24472578 24466207
100000 0 0 -1120567296 1005.79 100.00% 25255433 25249070
100000 0 0 -1018167296 1004.80 100.00% 26095603 26089234
100000 0 0 -915767296 1004.82 100.00% 26910357 26903988
99997 3 0 -813471744 1004.93 100.00% 27721765 27715397
100000 0 0 -710967296 1005.13 100.00% 28532102 28525735
100000 0 0 -608567296 1005.14 100.00% 29346832 29340464
100000 0 0 -506167296 1005.27 100.00% 30157946 30151579
100000 0 0 -403767296 1005.45 100.00% 30967314 30960949
100000 0 0 -301367296 1006.45 100.00% 31750492 31744133
100000 0 0 -198967296 1005.58 100.00% 32592619 32586255
100000 0 0 -96567296 1005.83 100.00% 33398972 33392610
100000 0 0 5832704 1005.83 100.00% 52754 46391
100000 0 0 108232704 1005.83 100.00% 867208 860845
99996 4 0 210452480 1006.17 100.00% 1679660 1673300
100000 0 0 313032704 1006.16 100.00% 2495297 2488936
100000 0 0 415432704 1007.59 100.00% 3304787 3298435
99990 10 0 517351424 1006.38 99.99% 4118942 4112584
100000 0 0 620232704 1006.47 100.00% 4936337 4929978
100000 0 0 722632704 1006.43 100.00% 5750501 5744142
100000 0 0 825032704 1006.76 100.00% 6562318 6555961
100000 0 0 927432704 1006.84 100.00% 7375433 7369077
99994 6 0 1029513216 1008.04 99.99% 8176785 8170437
99999 1 0 1132178432 1007.10 100.00% 8999951 8993596
100000 0 0 1234632704 1007.14 100.00% 9813419 9807064
100000 0 0 1337032704 1007.11 100.00% 10627131 10620776
99991 9 0 1438916608 1007.37 99.99% 11433498 11427146
99990 10 0 1541249024 1007.41 99.99% 12245684 12239331
99997 3 0 1644054528 1144.63 100.00% 11496144 11490553
100000 0 0 1746632704 1145.59 100.00% 12202844 12197258
100000 0 0 1849032704 1157.14 100.00% 12789000 12783469
100000 0 0 1951432704 1174.20 100.00% 13300866 13295416
99992 8 0 2053324800 1171.93 99.99% 14022179 14016719
100000 0 0 -2138734592 1171.84 100.00% 14725797 14720335
1000000 0 0 -198967296 10013.61 100.00% 3278739 3272348


Sender: Compaq G2 (Single CPU, pci 3c90x nic) running Red Hat Linux
release 7.1 (Seawolf) kernel 2.4.2-2
Receiver: Compaq G2 (Single CPU, pci 3c90x nic) running RHEL ES 2.1
(Pensacola) kernel 2.4.9-e.24
# Datagrams Dropped Duplicated Bytes Time (s) Efficiency Data bps Total
bps
100 0 0 409600 0.98 100.00% 3343054 3336537
100 0 0 512000 0.99 100.00% 4151563 4145086
100 0 0 614400 0.99 100.00% 4980545 4974068
100 0 0 716800 0.99 100.00% 5809233 5802756
100 0 0 819200 0.99 100.00% 6638447 6631970
100 0 0 921600 0.99 100.00% 7467692 7461215
100 0 0 1024000 0.99 100.00% 8296355 8289879
100 0 0 1126400 0.99 100.00% 9125463 9118986
100 0 0 1228800 0.99 100.00% 9954331 9947854
100 0 0 1331200 0.99 100.00% 10782206 10775730
100 0 0 1433600 0.99 100.00% 11612354 11605877
100 0 0 1536000 0.99 100.00% 12441634 12435158
100 0 0 1638400 0.99 100.00% 13270470 13263994
100 0 0 1740800 0.99 100.00% 14099955 14093478
100 0 0 1843200 0.99 100.00% 14928696 14922219
100 0 0 1945600 0.99 100.00% 15757692 15751216
100 0 0 2048000 0.99 100.00% 16586905 16580428
100 0 0 2150400 0.99 100.00% 17415962 17409485
100 0 0 2252800 0.99 100.00% 18244782 18238305
100 0 0 2355200 0.99 100.00% 19076981 19070503
100 0 0 2457600 0.99 100.00% 19896729 19890254
100 0 0 2560000 0.99 100.00% 20735705 20729228
100 0 0 2662400 0.99 100.00% 21562299 21555822
100 0 0 2764800 0.99 100.00% 22363689 22357220
100 0 0 2867200 0.99 100.00% 23218818 23212341
100 0 0 2969600 0.99 100.00% 24048512 24042035
100 0 0 3072000 0.99 100.00% 24877547 24871070
100 0 0 3174400 0.99 100.00% 25706531 25700054
100 0 0 3276800 0.99 100.00% 26535404 26528927
100 0 0 3379200 0.99 100.00% 27369668 27363190
100 0 0 3481600 0.99 100.00% 28192720 28186243
100 0 0 3584000 0.99 100.00% 29022667 29016190
100 0 0 3686400 0.99 100.00% 29852517 29846040
100 0 0 3788800 0.99 100.00% 30685890 30679412
100 0 0 3891200 0.99 100.00% 31511810 31505333
100 0 0 3993600 1.27 100.00% 25199275 25194228
100 0 0 4096000 0.99 100.00% 33167635 33161159
100 0 0 4198400 0.99 100.00% 33997146 33990669
100 0 0 4300800 0.99 100.00% 34825517 34819040
100 0 0 4403200 0.99 100.00% 35655949 35649472
100 0 0 4505600 0.99 100.00% 36484268 36477791
100 0 0 4608000 0.99 100.00% 37313045 37306568
100 0 0 4710400 0.99 100.00% 38141732 38135255
100 0 0 4812800 0.99 100.00% 38970128 38963652
100 0 0 4915200 0.99 100.00% 39800633 39794156
100 0 0 5017600 0.99 100.00% 40630541 40624064
100 0 0 5120000 0.99 100.00% 41457044 41450567
100 0 0 5222400 0.99 100.00% 42294530 42288052
100 0 0 5324800 0.99 100.00% 43116638 43110161
100 0 0 5427200 0.99 100.00% 43955732 43949254
1000 0 0 4096000 9.99 100.00% 3287075 3280668
1000 0 0 5120000 9.99 100.00% 4107231 4100823
1000 0 0 6144000 9.99 100.00% 4927407 4920999
1000 0 0 7168000 9.99 100.00% 5747563 5741156
1000 0 0 8192000 9.99 100.00% 6567726 6561319
1000 0 0 9216000 9.99 100.00% 7387889 7381481
1000 0 0 10240000 9.99 100.00% 8208062 8201654
1000 0 0 11264000 9.99 100.00% 9028205 9021797
1000 0 0 12288000 9.99 100.00% 9848401 9841994
1000 0 0 13312000 9.99 100.00% 10668568 10662160
1000 0 0 14336000 9.99 100.00% 11488733 11482325
1000 0 0 15360000 9.99 100.00% 12308909 12302501
1000 0 0 16384000 9.99 100.00% 13129079 13122672
1000 0 0 17408000 9.99 100.00% 13949236 13942829
1000 0 0 18432000 9.99 100.00% 14769395 14762988
1000 0 0 19456000 9.99 100.00% 15589647 15583240
1000 0 0 20480000 9.99 100.00% 16409770 16403363
1000 0 0 21504000 9.99 100.00% 17229904 17223496
1000 0 0 22528000 9.99 100.00% 18050106 18043699
1000 0 0 23552000 9.99 100.00% 18870278 18863871
1000 0 0 24576000 9.99 100.00% 19690411 19684004
1000 0 0 25600000 9.99 100.00% 20510617 20504209
1000 0 0 26624000 9.99 100.00% 21330753 21324346
1000 0 0 27648000 9.99 100.00% 22151002 22144595
1000 0 0 28672000 9.99 100.00% 22971145 22964737
1000 0 0 29696000 9.99 100.00% 23791295 23784888
1000 0 0 30720000 9.99 100.00% 24611444 24605036
1000 0 0 31744000 9.99 100.00% 25431586 25425179
1000 0 0 32768000 9.99 100.00% 26252056 26245648
1000 0 0 33792000 9.99 100.00% 27071977 27065570
1000 0 0 34816000 9.99 100.00% 27892132 27885725
1000 0 0 35840000 9.99 100.00% 28712315 28705907
1000 0 0 36864000 9.99 100.00% 29532481 29526073
1000 0 0 37888000 9.99 100.00% 30352552 30346145
1000 0 0 38912000 9.99 100.00% 31172884 31166476
1000 0 0 39936000 9.99 100.00% 31992961 31986554
1000 0 0 40960000 9.99 100.00% 32813192 32806784
1000 0 0 41984000 9.99 100.00% 33633328 33626920
1000 0 0 43008000 9.99 100.00% 34452593 34446185
1000 0 0 44032000 9.99 100.00% 35274492 35268084
1000 0 0 45056000 9.99 100.00% 36093957 36087549
1000 0 0 46080000 9.99 100.00% 36914047 36907640
1000 0 0 47104000 9.99 100.00% 37738188 37731780
1000 0 0 48128000 9.99 100.00% 38554360 38547952
1000 0 0 49152000 9.99 100.00% 39374580 39368173
1000 0 0 50176000 9.99 100.00% 40194698 40188291
1000 0 0 51200000 9.99 100.00% 41014715 41008308
1000 0 0 52224000 9.99 100.00% 41835288 41828880
1000 0 0 53248000 9.99 100.00% 42655189 42648781
1000 0 0 54272000 9.99 100.00% 43475349 43468941
10000 0 0 40960000 99.99 100.00% 3283573 3277172
10000 0 0 51200000 99.99 100.00% 4102865 4096464
10000 0 0 61440000 99.99 100.00% 4922159 4915759
10000 0 0 71680000 99.99 100.00% 5741452 5735051
10000 0 0 81920000 99.99 100.00% 6560744 6554343
10000 0 0 92160000 99.99 100.00% 7380039 7373638
10000 0 0 102400000 99.99 100.00% 8199330 8192929
10000 0 0 112640000 99.99 100.00% 9018624 9012224
10000 0 0 122880000 99.99 100.00% 9837919 9831519
10000 0 0 133120000 99.99 100.00% 10657209 10650809
10000 0 0 143360000 99.99 100.00% 11476504 11470103
10000 0 0 153600000 99.99 100.00% 12295797 12289396
10000 0 0 163840000 99.99 100.00% 13115091 13108690
10000 0 0 174080000 99.99 100.00% 13934384 13927983
10000 0 0 184320000 99.99 100.00% 14753676 14747275
10000 0 0 194560000 99.99 100.00% 15572972 15566571
10000 0 0 204800000 99.99 100.00% 16392272 16385871
10000 0 0 215040000 99.99 100.00% 17211557 17205156
10000 0 0 225280000 99.99 100.00% 18030852 18024451
10000 0 0 235520000 99.99 100.00% 18850143 18843742
10000 0 0 245760000 99.99 100.00% 19669437 19663037
10000 0 0 256000000 99.99 100.00% 20488734 20482333
10000 0 0 266240000 99.99 100.00% 21308022 21301621
10000 0 0 276480000 99.99 100.00% 22127319 22120918
10000 0 0 286720000 99.99 100.00% 22946610 22940209
10000 0 0 296960000 99.99 100.00% 23765914 23759513
10000 0 0 307200000 99.99 100.00% 24585200 24578799
10000 0 0 317440000 99.99 100.00% 25404528 25398127
10000 0 0 327680000 99.99 100.00% 26223714 26217314
10000 0 0 337920000 99.99 100.00% 27043146 27036745
10000 0 0 348160000 99.99 100.00% 27862374 27855973
10000 0 0 358400000 99.99 100.00% 28681664 28675263
10000 0 0 368640000 99.99 100.00% 29500951 29494550
10000 0 0 378880000 99.99 100.00% 30320250 30313850
10000 0 0 389120000 99.99 100.00% 31139551 31133151
10000 0 0 399360000 99.99 100.00% 31958839 31952439
10000 0 0 409600000 99.99 100.00% 32778083 32771682
10000 0 0 419840000 99.99 100.00% 33597487 33591086
10000 0 0 430080000 99.99 100.00% 34416720 34410319
10000 0 0 440320000 99.99 100.00% 35236021 35229620
10000 0 0 450560000 99.99 100.00% 36055292 36048891
10000 0 0 460800000 99.99 100.00% 36874605 36868204
10000 0 0 471040000 99.99 100.00% 37693894 37687494
10000 0 0 481280000 99.99 100.00% 38513185 38506784
10000 0 0 491520000 99.99 100.00% 39332485 39326084
10000 0 0 501760000 99.99 100.00% 40151770 40145369
10000 0 0 512000000 99.99 100.00% 40971076 40964675
10000 0 0 522240000 99.99 100.00% 41790372 41783972
10000 0 0 532480000 99.99 100.00% 42609648 42603247
10000 0 0 542720000 99.99 100.00% 43428951 43422550
100000 0 0 409600000 999.99 100.00% 3283223 3276823
100000 0 0 512000000 999.99 100.00% 4102422 4096022
100000 0 0 614400000 1000.00 100.00% 4921586 4915186
100000 0 0 716800000 999.99 100.00% 5740840 5734440
100000 0 0 819200000 999.99 100.00% 6560046 6553646
100000 0 0 921600000 999.99 100.00% 7379252 7372852
100000 0 0 1024000000 999.99 100.00% 8198458 8192058
100000 0 0 1126400000 999.99 100.00% 9017664 9011263
100000 0 0 1228800000 999.99 100.00% 9836870 9830470
100000 0 0 1331200000 999.99 100.00% 10656075 10649675
100000 0 0 1433600000 999.99 100.00% 11475282 11468881
100000 0 0 1536000000 999.99 100.00% 12294487 12288087
100000 0 0 1638400000 999.99 100.00% 13113709 13107309
100000 0 0 1740800000 999.99 100.00% 13932899 13926499
100000 0 0 1843200000 999.99 100.00% 14752105 14745705
100000 0 0 1945600000 999.99 100.00% 15571311 15564911
99994 6 0 2047877120 999.99 99.99% 16389533 16383134
100000 0 0 -2144567296 999.99 100.00% 17209723 17203323
99976 24 0 -2042707968 999.99 99.98% 18024631 18018232
100000 0 0 -1939767296 999.99 100.00% 18848133 18841733
100000 0 0 -1837367296 999.99 100.00% 19667340 19660940
100000 0 0 -1734967296 999.99 100.00% 20486542 20480142
100000 0 0 -1632567296 999.99 100.00% 21305746 21299346
100000 0 0 -1530167296 999.99 100.00% 22124953 22118553
99974 26 0 -1428512768 1000.00 99.97% 22937962 22931563
100000 0 0 -1325367296 999.99 100.00% 23763363 23756963
100000 0 0 -1222967296 999.99 100.00% 24582571 24576171
100000 0 0 -1120567296 999.99 100.00% 25401775 25395375
100000 0 0 -1018167296 999.99 100.00% 26220979 26214579
100000 0 0 -915767296 999.99 100.00% 27040186 27033786
100000 0 0 -813367296 999.99 100.00% 27859391 27852991
100000 0 0 -710967296 999.99 100.00% 28678598 28672198
100000 0 0 -608567296 999.99 100.00% 29497801 29491401
100000 0 0 -506167296 999.99 100.00% 30317006 30310606
100000 0 0 -403767296 999.99 100.00% 31136213 31129813
100000 0 0 -301367296 999.99 100.00% 31955419 31949019
100000 0 0 -198967296 999.99 100.00% 32774625 32768225
100000 0 0 -96567296 999.99 100.00% 33593828 33587428
100000 0 0 5832704 999.99 100.00% 53062 46662
99991 9 0 107836416 999.99 99.99% 869097 862697
100000 0 0 210632704 999.99 100.00% 1691473 1685073
100000 0 0 313032704 999.99 100.00% 2510679 2504279
100000 0 0 415432704 999.99 100.00% 3329884 3323484
99976 24 0 516677632 999.99 99.98% 4139848 4133449
100000 0 0 620232704 999.99 100.00% 4968296 4961896
100000 0 0 722632704 999.99 100.00% 5787501 5781101
100000 0 0 825032704 999.99 100.00% 6606707 6600307
100000 0 0 927432704 999.99 100.00% 7425912 7419512
100000 0 0 1029832704 999.99 100.00% 8245118 8238718
100000 0 0 1132232704 999.99 100.00% 9064322 9057922
999997 3 0 -198979584 10000.04 100.00% 3283177 3276777



udptest.pl
#!/usr/bin/perl -w

use strict;

use constant TRUE => 1;
use constant FALSE => 0;
use constant MAX_PACKET_SIZE => 65507;
use constant MAX_PACKET_NUM => 1000000;

my $ipaddr = "192.168.0.2";
my $numPackets = 100; #default number of packets to send
my $packetSize = 4096; #default size for updtest
my $delay = 1000; #default delay for udptest

print "Running udptest with options\n";
while (TRUE) {
print "IPADDRESS\tNUMPACKETS\tPACKETSIZE\tDELAY\n";
print "$ipaddr\t$numPackets\t\t$packetSize\t\t$delay \n";
`/root/udptest $ipaddr $numPackets $packetSize $delay`;
&incPacketSize();
}

sub incPacketSize {
$packetSize += 1024;
if ($packetSize > MAX_PACKET_SIZE) {
$packetSize = 4096;
&incNumPackets();
}
}

sub incNumPackets {
$numPackets *= 10;
if ($numPackets > MAX_PACKET_NUM) {
$numPackets = 100;
&decDelay();
}
}

sub decDelay {
if ($delay > 100) {
$delay -= 100;
} elsif ($delay <= 100) {
if ($delay == 10) {
exit(1);
}
$delay -= 10;
}
}

Hi mmercier:


Good points, but if I understand Stefano correctly, what he is talking
about is a very sudden & unexpected shutdown of receiving <multicast>
UDP packets, which I have experienced in the past (and which turned out
in <that> case to be directly tied to a bug within the ethernet driver).

Yes, absolutely, UDP is most definitely a protocol that may have dropped
packets, and you can see that as the transfer rate increases, the
probability of dropped packets increases as well.

Very good script, by the way.

With regards to crossover cable for regular (or unicast) UDP packets:
that <should> be transparent from the application perspective.

Stefano: the only other thing that comes to mind that may be a
contributory factor is if you are attempting to receive multicast
packets from another LAN that is connected to your Cisco router and then
being received on another branch, <perhaps> there is something going
wrong in the routing of the multicast packets? There are two main
multicast routing protocols, DVMRP (for RIP) and MOSPF (for OSPF) (and
there are others..), but if they are somehow misconfigured, the router
may decide to "prune" back a branch, and then you might suddenly stop
getting packets (this is just pure speculation, since I don't know how
it is configured).

Anyway, keep us posted and let us know what the problem turned out to
be.

g.