Re: packetloss, on e1000e worse than r8169?

[Eric Dumazet <dada1@cosmosbay.com>]

Denys Fedoryshchenko a e'crit :
> On Mon, 16 Jun 2008 23:44:07 +0200, Eric Dumazet wrote
> 
> opreport -l /mnt/flash/vmlinux |more
> Here is oprofile
> CPU: Core 2, speed 2397.64 MHz (estimated)
> Counted CPU_CLK_UNHALTED events (Clock cycles when not halted) with a unit
> mask of 0x00 (Unhalted core cycles) count 100000
> samples  %        symbol name
> 25409    15.0068  mwait_idle
> 14330     8.4634  ip_route_input
> 7827      4.6227  irq_entries_start
> 6488      3.8319  dev_queue_xmit
> 5497      3.2466  __qdisc_run
> 5033      2.9725  __slab_free
> 3569      2.1079  native_read_tsc
> 3560      2.1026  ip_rcv
> 3520      2.0789  __alloc_skb
> 3435      2.0287  __kmalloc_track_caller
> 3381      1.9968  kmem_cache_alloc
> 3340      1.9726  ip_forward
> 3289      1.9425  kfree
> 
> MegaRouter-KARAM /lib # opreport
> CPU: Core 2, speed 2397.64 MHz (estimated)
> Counted CPU_CLK_UNHALTED events (Clock cycles when not halted) with a unit
> mask of 0x00 (Unhalted core cycles) count 100000
> CPU_CLK_UNHALT...|
>   samples|      %|
> ------------------
>    612990 64.5673 vmlinux
>    276274 29.1004 e1000e
>     31470  3.3148 ip_tables

How often is iptables used on your machine ?

>      9676  1.0192 libzebra.so.0.0.0
>      3763  0.3964 oprofiled
> 
> MegaRouter-KARAM ~ # opreport image:/e1000e -l
> CPU: Core 2, speed 2397.64 MHz (estimated)
> Counted CPU_CLK_UNHALTED events (Clock cycles when not halted) with a unit
> mask of 0x00 (Unhalted core cycles) count 100000
> warning: could not check that the binary file /e1000e has not been modified
> since the profile was taken. Results may be inaccurate.
> samples  %        symbol name
> 144449   25.7521  e1000_irq_enable

I wonder why this one is called so often. If your
interface is really flooded with packets, we should not
exit from NAPI polling...


> 97006    17.2941  e1000_intr_msi
> 95009    16.9380  e1000_clean_rx_irq
> 87833    15.6587  e1000_xmit_frame
> 53723     9.5776  e1000_clean_tx_irq
> 26546     4.7326  e1000_clean
> 19968     3.5599  e1000_alloc_rx_buffers
> 11941     2.1288  e1000_receive_skb
> 6578      1.1727  e1000_update_itr
> 5864      1.0454  e1000_desc_unused
> 4847      0.8641  e1000_maybe_stop_tx
> 3537      0.6306  e1000_put_txbuf
> 3490      0.6222  e1000_rx_checksum
> 107       0.0191  e1000e_update_stats
> 9         0.0016  e1000_acquire_swflag_ich8lan
> 7         0.0012  e1000_release_swflag_ich8lan
> 5        8.9e-04  e1000e_read_phy_reg_mdic
> 1        1.8e-04  e1000_get_settings
> 1        1.8e-04  e1000_ioctl