lagg speed trouble

[Vyacheslav Kulikovskyy]

i have sever with two 1G links (em) aggregated by lagg0

after 1700Megabits i have collisions/errors on lagg0 port, but not on em0
or em1

I'm using nginx in own CDN. and server don't limited my mbufs, irq, or
anything else.. only lagg0 errors (

netstat -w 1 -I em0
            input          (em0)           output
   packets  errs idrops      bytes    packets  errs      bytes colls
     43871     0     0    2726437      38304     0  108063773     0
     43417     0     0    2700512      39084     0  109215143     0
     43474     0     0    2701344      39303     0  108373730     0
     43755     0     0    2717689      39023     0  108766820     0
     43960     0     0    2733462      39476     0  109030307     0
     44675     0     0    2776654      38708     0  107313936     0
     44082     0     0    2734293      39089     0  108897889     0

netstat -w 1 -I em1
            input          (em1)           output
   packets  errs idrops      bytes    packets  errs      bytes colls
     43754     0     0    2722677      38943     0  108504216     0
     44561     0     0    2778854      39107     0  108418763     0
     44773     0     0    2784606      39006     0  108799148     0
     45134     0     0    2814622      39137     0  108557494     0
     44604     0     0    2770745      38998     0  107942619     0
     44813     0     0    2789991      38901     0  108438247     0

netstat -w 1 -I lagg0
            input        (lagg0)           output
   packets  errs idrops      bytes    packets  errs      bytes colls
     87964     0     0    5474019      78172  1964  222220549     0
     88842     0     0    5533987      78852  1811  222578109     0
     87687     0     0    5454717      77279  2416  222286391     0
     87995     0     0    5471653      78090  2040  223488046     0
     88314     0     0    5493348      78495  1994  222548964     0
     88411     0     0    5502818      78228  1949  222214374     0

how i can get full link speed on this server?