Re: [Bug #11308] tbench regression on each kernel release from 2.6.22 -> 2.6.28

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



David Miller a écrit :
From: Ingo Molnar <mingo@xxxxxxx>
Date: Mon, 17 Nov 2008 19:49:51 +0100

* Ingo Molnar <mingo@xxxxxxx> wrote:

4> The place for the sock_rfree() hit looks a bit weird, and i'll
investigate it now a bit more to place the real overhead point properly. (i already mapped the test-bit overhead: that comes from napi_disable_pending())
ok, here's a new set of profiles. (again for tbench 64-thread on a 16-way box, with v2.6.28-rc5-19-ge14c8bf and with the kernel config i posted before.)

Again, do a non-NMI profile and the top (at least for me)
looks like this:

samples  %        app name                 symbol name
473       6.3928  vmlinux                  finish_task_switch
349       4.7169  vmlinux                  tcp_v4_rcv
327       4.4195  vmlinux                  U3copy_from_user
322       4.3519  vmlinux                  tl0_linux32
178       2.4057  vmlinux                  tcp_ack
170       2.2976  vmlinux                  tcp_sendmsg
167       2.2571  vmlinux                  U3copy_to_user

That tcp_v4_rcv() hit is %98 on the wake_up() call it does.



Another profile from my tree (net-next-2.6 + some patches), on my machine


CPU: Core 2, speed 3000.22 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
223265    9.2711  __copy_user_zeroing_intel
87525     3.6345  __copy_user_intel
73203     3.0398  tcp_sendmsg
53229     2.2103  netif_rx
53041     2.2025  tcp_recvmsg
47241     1.9617  sysenter_past_esp
42888     1.7809  __copy_from_user_ll
40858     1.6966  tcp_transmit_skb
39390     1.6357  __switch_to
37363     1.5515  dst_release
36823     1.5291  __sk_dst_check_get
36050     1.4970  tcp_v4_rcv
35829     1.4878  __do_softirq
32333     1.3426  tcp_rcv_established
30451     1.2645  tcp_clean_rtx_queue
29758     1.2357  ip_queue_xmit
28497     1.1833  __copy_to_user_ll
28119     1.1676  release_sock
25218     1.0472  lock_sock_nested
23701     0.9842  __inet_lookup_established
23463     0.9743  tcp_ack
22989     0.9546  netif_receive_skb
21880     0.9086  sched_clock_cpu
20730     0.8608  tcp_write_xmit
20372     0.8460  ip_rcv
20336     0.8445  local_bh_enable
19153     0.7953  __update_sched_clock
18603     0.7725  skb_release_data
17020     0.7068  local_bh_enable_ip
16932     0.7031  process_backlog
16299     0.6768  ip_finish_output
16279     0.6760  dev_queue_xmit
15858     0.6585  sock_recvmsg
15641     0.6495  native_read_tsc
15454     0.6417  sock_wfree
15366     0.6381  update_curr
14585     0.6056  sys_socketcall
14564     0.6048  __alloc_skb
14519     0.6029  __tcp_select_window
14417     0.5987  tcp_current_mss
14391     0.5976  nf_iterate
14221     0.5905  page_address
14122     0.5864  local_bh_disable



--
To unsubscribe from this list: send the line "unsubscribe kernel-testers" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux