Here is a tcpdump of the benchmark, actually a snippet of somewhere in the middle of
the transfer.
MTU was set to 9014 bytes jumbo frames which is actually about 2-3 MB/s slower than
MTU 1500 I think. SO_SNDBUF and SO_RECVBUF are 65536.

23:53:13.367925 IP fserver.microsoft-ds > host1.1076: P 344831152:344835311(4159) ack 680922 win 698
23:53:13.368023 IP fserver.microsoft-ds > host1.1076: . 344835311:344844271(8960) ack 680922 win 698
23:53:13.368039 IP fserver.microsoft-ds > host1.1076: . 344844271:344853231(8960) ack 680922 win 698
23:53:13.368047 IP fserver.microsoft-ds > host1.1076: . 344853231:344862191(8960) ack 680922 win 698
23:53:13.368055 IP fserver.microsoft-ds > host1.1076: . 344862191:344871151(8960) ack 680922 win 698
23:53:13.368057 IP fserver.microsoft-ds > host1.1076: P 344871151:344873270(2119) ack 680922 win 698
23:53:13.368073 IP fserver.microsoft-ds > host1.1076: . 344873270:344882230(8960) ack 680922 win 698
23:53:13.368081 IP fserver.microsoft-ds > host1.1076: . 344882230:344891190(8960) ack 680922 win 698
23:53:13.368084 IP fserver.microsoft-ds > host1.1076: P 344891190:344896814(5624) ack 680922 win 698
23:53:13.368390 IP host1.1076 > fserver.microsoft-ds: P 680922:680985(63) ack 344835311 win 33760
23:53:13.368515 IP host1.1076 > fserver.microsoft-ds: . ack 344862191 win 35840
23:53:13.368568 IP fserver.microsoft-ds > host1.1076: . 344896814:344905774(8960) ack 680985 win 698
23:53:13.368582 IP fserver.microsoft-ds > host1.1076: . 344905774:344914734(8960) ack 680985 win 698
23:53:13.368591 IP fserver.microsoft-ds > host1.1076: . 344914734:344923694(8960) ack 680985 win 698
23:53:13.368604 IP fserver.microsoft-ds > host1.1076: . 344923694:344933871(10177) ack 680985 win 698
23:53:13.368764 IP host1.1076 > fserver.microsoft-ds: . ack 344896814 win 35840
23:53:13.368792 IP fserver.microsoft-ds > host1.1076: . 344933871:344951791(17920) ack 680985 win 698
23:53:13.368797 IP fserver.microsoft-ds > host1.1076: P 344951791:344958317(6526) ack 680985 win 698
23:53:13.368765 IP host1.1076 > fserver.microsoft-ds: P 680985:681048(63) ack 344896814 win 35840
23:53:13.368877 IP fserver.microsoft-ds > host1.1076: P 344958317:344962476(4159) ack 681048 win 698
23:53:13.369014 IP host1.1076 > fserver.microsoft-ds: . ack 344914734 win 35840
23:53:13.369286 IP host1.1076 > fserver.microsoft-ds: . ack 344942831 win 35840
23:53:13.369561 IP host1.1076 > fserver.microsoft-ds: P 681048:681111(63) ack 344962476 win 35840
23:53:13.369562 IP host1.1076 > fserver.microsoft-ds: . ack 344962476 win 35840
23:53:13.369563 IP host1.1076 > fserver.microsoft-ds: P 681111:681174(63) ack 344962476 win 35840
23:53:13.369631 IP fserver.microsoft-ds > host1.1076: P 344962476:344966635(4159) ack 681174 win 698
23:53:13.369718 IP fserver.microsoft-ds > host1.1076: . 344966635:344975595(8960) ack 681174 win 698
23:53:13.369733 IP fserver.microsoft-ds > host1.1076: . 344975595:344984555(8960) ack 681174 win 698
23:53:13.369743 IP fserver.microsoft-ds > host1.1076: . 344984555:344993515(8960) ack 681174 win 698
23:53:13.369768 IP fserver.microsoft-ds > host1.1076: . 344993515:345002475(8960) ack 681174 win 698
23:53:13.369771 IP fserver.microsoft-ds > host1.1076: P 345002475:345004342(1867) ack 681174 win 698
23:53:13.369786 IP fserver.microsoft-ds > host1.1076: . 345004342:345013302(8960) ack 681174 win 698
23:53:13.369797 IP fserver.microsoft-ds > host1.1076: . 345013302:345022262(8960) ack 681174 win 698
23:53:13.369800 IP fserver.microsoft-ds > host1.1076: P 345022262:345028138(5876) ack 681174 win 698
23:53:13.370130 IP host1.1076 > fserver.microsoft-ds: P 681174:681237(63) ack 344966635 win 33760
23:53:13.370256 IP host1.1076 > fserver.microsoft-ds: . ack 344993515 win 35840
23:53:13.370326 IP fserver.microsoft-ds > host1.1076: . 345028138:345063978(35840) ack 681237 win 698
23:53:13.370555 IP host1.1076 > fserver.microsoft-ds: . ack 345028138 win 35840
23:53:13.370577 IP fserver.microsoft-ds > host1.1076: . 345063978:345081898(17920) ack 681237 win 698
23:53:13.370582 IP fserver.microsoft-ds > host1.1076: P 345081898:345089641(7743) ack 681237 win 698
23:53:13.370556 IP host1.1076 > fserver.microsoft-ds: P 681237:681300(63) ack 345028138 win 35840
23:53:13.370662 IP fserver.microsoft-ds > host1.1076: P 345089641:345093800(4159) ack 681300 win 698
23:53:13.371068 IP host1.1076 > fserver.microsoft-ds: . ack 345072938 win 35840
23:53:13.371266 IP host1.1076 > fserver.microsoft-ds: P 681300:681363(63) ack 345093800 win 35840
23:53:13.371266 IP host1.1076 > fserver.microsoft-ds: . ack 345093800 win 35840
23:53:13.371267 IP host1.1076 > fserver.microsoft-ds: P 681363:681426(63) ack 345093800 win 35840
23:53:13.371337 IP fserver.microsoft-ds > host1.1076: P 345093800:345097959(4159) ack 681426 win 698
23:53:13.371428 IP fserver.microsoft-ds > host1.1076: . 345097959:345106919(8960) ack 681426 win 698
23:53:13.371441 IP fserver.microsoft-ds > host1.1076: . 345106919:345115879(8960) ack 681426 win 698
23:53:13.371448 IP fserver.microsoft-ds > host1.1076: . 345115879:345124839(8960) ack 681426 win 698
23:53:13.371470 IP fserver.microsoft-ds > host1.1076: . 345124839:345133799(8960) ack 681426 win 698
23:53:13.371472 IP fserver.microsoft-ds > host1.1076: P 345133799:345135414(1615) ack 681426 win 698
23:53:13.371487 IP fserver.microsoft-ds > host1.1076: . 345135414:345144374(8960) ack 681426 win 698
23:53:13.371495 IP fserver.microsoft-ds > host1.1076: . 345144374:345153334(8960) ack 681426 win 698
23:53:13.371499 IP fserver.microsoft-ds > host1.1076: P 345153334:345159462(6128) ack 681426 win 698
23:53:13.371838 IP host1.1076 > fserver.microsoft-ds: P 681426:681489(63) ack 345097959 win 33760
23:53:13.371963 IP host1.1076 > fserver.microsoft-ds: . ack 345124839 win 35840
23:53:13.372014 IP fserver.microsoft-ds > host1.1076: . 345159462:345168422(8960) ack 681489 win 698
23:53:13.372025 IP fserver.microsoft-ds > host1.1076: . 345168422:345177382(8960) ack 681489 win 698
23:53:13.372032 IP fserver.microsoft-ds > host1.1076: . 345177382:345186342(8960) ack 681489 win 698
23:53:13.372044 IP fserver.microsoft-ds > host1.1076: . 345186342:345196519(10177) ack 681489 win 698
23:53:13.372236 IP host1.1076 > fserver.microsoft-ds: . ack 345153334 win 35840
23:53:13.372263 IP fserver.microsoft-ds > host1.1076: . 345196519:345214439(17920) ack 681489 win 698
23:53:13.372267 IP fserver.microsoft-ds > host1.1076: P 345214439:345220965(6526) ack 681489 win 698
23:53:13.372484 IP host1.1076 > fserver.microsoft-ds: . ack 345177382 win 35840
23:53:13.372485 IP host1.1076 > fserver.microsoft-ds: P 681489:681552(63) ack 345177382 win 35840
23:53:13.372561 IP fserver.microsoft-ds > host1.1076: P 345220965:345225124(4159) ack 681552 win 698
23:53:13.372735 IP host1.1076 > fserver.microsoft-ds: . ack 345205479 win 35840
23:53:13.372966 IP host1.1076 > fserver.microsoft-ds: P 681552:681615(63) ack 345225124 win 35840
23:53:13.372966 IP host1.1076 > fserver.microsoft-ds: . ack 345225124 win 35840
23:53:13.372967 IP host1.1076 > fserver.microsoft-ds: P 681615:681678(63) ack 345225124 win 35840
23:53:13.373036 IP fserver.microsoft-ds > host1.1076: P 345225124:345229283(4159) ack 681678 win 698
23:53:13.373126 IP fserver.microsoft-ds > host1.1076: . 345229283:345238243(8960) ack 681678 win 698
23:53:13.373136 IP fserver.microsoft-ds > host1.1076: . 345238243:345247203(8960) ack 681678 win 698
23:53:13.373144 IP fserver.microsoft-ds > host1.1076: . 345247203:345256163(8960) ack 681678 win 698
23:53:13.373152 IP fserver.microsoft-ds > host1.1076: . 345256163:345265123(8960) ack 681678 win 698
23:53:13.373169 IP fserver.microsoft-ds > host1.1076: P 345265123:345266486(1363) ack 681678 win 698
23:53:13.373183 IP fserver.microsoft-ds > host1.1076: . 345266486:345275446(8960) ack 681678 win 698
23:53:13.373192 IP fserver.microsoft-ds > host1.1076: . 345275446:345284406(8960) ack 681678 win 698
23:53:13.373195 IP fserver.microsoft-ds > host1.1076: P 345284406:345290786(6380) ack 681678 win 698
23:53:13.373535 IP host1.1076 > fserver.microsoft-ds: P 681678:681741(63) ack 345229283 win 33760
23:53:13.373661 IP host1.1076 > fserver.microsoft-ds: . ack 345256163 win 35840
23:53:13.373735 IP fserver.microsoft-ds > host1.1076: . 345290786:345326626(35840) ack 681741 win 698
23:53:13.373962 IP host1.1076 > fserver.microsoft-ds: . ack 345290786 win 35840
23:53:13.373985 IP fserver.microsoft-ds > host1.1076: . 345326626:345344546(17920) ack 681741 win 698
23:53:13.373990 IP fserver.microsoft-ds > host1.1076: P 345344546:345352289(7743) ack 681741 win 698
23:53:13.373964 IP host1.1076 > fserver.microsoft-ds: P 681741:681804(63) ack 345290786 win 35840
23:53:13.374067 IP fserver.microsoft-ds > host1.1076: P 345352289:345356448(4159) ack 681804 win 698
23:53:13.374335 IP host1.1076 > fserver.microsoft-ds: . ack 345326626 win 35840
23:53:13.374676 IP host1.1076 > fserver.microsoft-ds: P 681804:681867(63) ack 345356448 win 35840
23:53:13.374677 IP host1.1076 > fserver.microsoft-ds: . ack 345356448 win 35840
23:53:13.374678 IP host1.1076 > fserver.microsoft-ds: P 681867:681930(63) ack 345356448 win 35840
23:53:13.374762 IP fserver.microsoft-ds > host1.1076: P 345356448:345360607(4159) ack 681930 win 698
23:53:13.374852 IP fserver.microsoft-ds > host1.1076: . 345360607:345369567(8960) ack 681930 win 698
23:53:13.374866 IP fserver.microsoft-ds > host1.1076: . 345369567:345378527(8960) ack 681930 win 698
23:53:13.374872 IP fserver.microsoft-ds > host1.1076: . 345378527:345387487(8960) ack 681930 win 698
23:53:13.374897 IP fserver.microsoft-ds > host1.1076: . 345387487:345396447(8960) ack 681930 win 698
23:53:13.374899 IP fserver.microsoft-ds > host1.1076: P 345396447:345397558(1111) ack 681930 win 698
23:53:13.374912 IP fserver.microsoft-ds > host1.1076: . 345397558:345406518(8960) ack 681930 win 698
23:53:13.374920 IP fserver.microsoft-ds > host1.1076: . 345406518:345415478(8960) ack 681930 win 698
23:53:13.374924 IP fserver.microsoft-ds > host1.1076: P 345415478:345422110(6632) ack 681930 win 698
23:53:13.375135 IP host1.1076 > fserver.microsoft-ds: P 681930:681993(63) ack 345360607 win 33760
23:53:13.375387 IP host1.1076 > fserver.microsoft-ds: . ack 345387487 win 35840
23:53:13.375419 IP fserver.microsoft-ds > host1.1076: . 345422110:345457950(35840) ack 681993 win 698
23:53:13.375640 IP host1.1076 > fserver.microsoft-ds: . ack 345415478 win 35840
23:53:13.375655 IP fserver.microsoft-ds > host1.1076: . 345457950:345475870(17920) ack 681993 win 698
23:53:13.375660 IP fserver.microsoft-ds > host1.1076: P 345475870:345483613(7743) ack 681993 win 698
23:53:13.375893 IP host1.1076 > fserver.microsoft-ds: . ack 345431070 win 35840
23:53:13.375894 IP host1.1076 > fserver.microsoft-ds: P 681993:682056(63) ack 345431070 win 35840
23:53:13.375974 IP fserver.microsoft-ds > host1.1076: P 345483613:345487772(4159) ack 682056 win 698
23:53:13.376146 IP host1.1076 > fserver.microsoft-ds: . ack 345466910 win 35840
23:53:13.376377 IP host1.1076 > fserver.microsoft-ds: P 682056:682119(63) ack 345487772 win 35840
23:53:13.376377 IP host1.1076 > fserver.microsoft-ds: . ack 345487772 win 35840
23:53:13.376378 IP host1.1076 > fserver.microsoft-ds: P 682119:682182(63) ack 345487772 win 35840
23:53:13.376447 IP fserver.microsoft-ds > host1.1076: P 345487772:345491931(4159) ack 682182 win 698
23:53:13.376536 IP fserver.microsoft-ds > host1.1076: . 345491931:345500891(8960) ack 682182 win 698
23:53:13.376553 IP fserver.microsoft-ds > host1.1076: . 345500891:345509851(8960) ack 682182 win 698
23:53:13.376561 IP fserver.microsoft-ds > host1.1076: . 345509851:345518811(8960) ack 682182 win 698
23:53:13.376583 IP fserver.microsoft-ds > host1.1076: . 345518811:345527771(8960) ack 682182 win 698
23:53:13.376586 IP fserver.microsoft-ds > host1.1076: P 345527771:345528630(859) ack 682182 win 698
23:53:13.376600 IP fserver.microsoft-ds > host1.1076: . 345528630:345537590(8960) ack 682182 win 698
23:53:13.376607 IP fserver.microsoft-ds > host1.1076: . 345537590:345546550(8960) ack 682182 win 698
23:53:13.376612 IP fserver.microsoft-ds > host1.1076: P 345546550:345553434(6884) ack 682182 win 698
23:53:13.376821 IP host1.1076 > fserver.microsoft-ds: P 682182:682245(63) ack 345491931 win 33760
23:53:13.377071 IP host1.1076 > fserver.microsoft-ds: . ack 345518811 win 35840
23:53:13.377101 IP fserver.microsoft-ds > host1.1076: . 345553434:345589274(35840) ack 682245 win 698
23:53:13.377325 IP host1.1076 > fserver.microsoft-ds: . ack 345546550 win 35840
23:53:13.377341 IP fserver.microsoft-ds > host1.1076: . 345589274:345607194(17920) ack 682245 win 698
23:53:13.377345 IP fserver.microsoft-ds > host1.1076: P 345607194:345614937(7743) ack 682245 win 698
23:53:13.377577 IP host1.1076 > fserver.microsoft-ds: . ack 345571354 win 35840
23:53:13.377578 IP host1.1076 > fserver.microsoft-ds: P 682245:682308(63) ack 345571354 win 35840
23:53:13.377659 IP fserver.microsoft-ds > host1.1076: P 345614937:345619096(4159) ack 682308 win 698
23:53:13.377824 IP host1.1076 > fserver.microsoft-ds: . ack 345598234 win 35840
23:53:13.378085 IP host1.1076 > fserver.microsoft-ds: P 682308:682371(63) ack 345619096 win 35840
23:53:13.378086 IP host1.1076 > fserver.microsoft-ds: . ack 345619096 win 35840
23:53:13.378086 IP host1.1076 > fserver.microsoft-ds: P 682371:682434(63) ack 345619096 win 35840
23:53:13.378165 IP fserver.microsoft-ds > host1.1076: P 345619096:345623255(4159) ack 682434 win 698
23:53:13.378252 IP fserver.microsoft-ds > host1.1076: . 345623255:345632215(8960) ack 682434 win 698
23:53:13.378264 IP fserver.microsoft-ds > host1.1076: . 345632215:345641175(8960) ack 682434 win 698
23:53:13.378270 IP fserver.microsoft-ds > host1.1076: . 345641175:345650135(8960) ack 682434 win 698
23:53:13.378278 IP fserver.microsoft-ds > host1.1076: . 345650135:345659095(8960) ack 682434 win 698
23:53:13.378280 IP fserver.microsoft-ds > host1.1076: P 345659095:345659702(607) ack 682434 win 698
23:53:13.378309 IP fserver.microsoft-ds > host1.1076: . 345659702:345668662(8960) ack 682434 win 698
23:53:13.378320 IP fserver.microsoft-ds > host1.1076: . 345668662:345677622(8960) ack 682434 win 698
23:53:13.378326 IP fserver.microsoft-ds > host1.1076: P 345677622:345684758(7136) ack 682434 win 698