On 22 February 2011 14:09, Patrick Lamaiziere <patf...@davenulle.org> wrote: > (4.8/amd64) > > Hello, > > I'm using two ethernet cards Intel 1000/PRO quad ports (gigabit) on a > firewall (one fiber and one copper). > > The problem is that we don't get more than ~320 Mbits/s of bandwith > beetween the internal networks and internet (gigabit). > > As far I can see, on load there is a number of "Ierr" on the interface > connected to Internet (between 1% to 5%). > > Also the interrupt rate on this card is around ~7500 (using systat). In > the em(4) driver, there is a limitation of the interrupt rate at 8000/s. > > if_em.h > /* > * MAX_INTS_PER_SEC (ITR - Interrupt Throttle Register) > * The Interrupt Throttle Register (ITR) limits the delivery of > interrupts > * to a reasonable rate by providing a guaranteed inter-interrupt delay > * between interrupts asserted by the Ethernet controller. > */ > #define MAX_INTS_PER_SEC 8000 > > Do you think I can increase this value? The interrupt rate of the > machine is at max ~60% (top). > > Other ideas to increase the bandwith would be welcome too. I don't > think the limitation come from PF because I don't see any congestion. > > thanks, regards. > > ------ > dmesg: > em0 at pci5 dev 0 function 0 "Intel PRO/1000 QP (82571EB)" rev > 0x06: apic 1 int 13 (irq 14), address 00:15:17:ed:98:9d > > em4 at pci9 dev 0 function 0 "Intel PRO/1000 QP (82575GB)" rev 0x02: > apic 1 int 23 (irq 11), address 00:1b:21:38:e0:80 > >
How exactly are you measuring the bandwidth ? What does tcpbench tells you ?
