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From: Eric Dumazet <eric.dumazet@gmail.com>
To: Thomas Graf <tgraf@infradead.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>,
	David Miller <davem@davemloft.net>,
	rick.jones2@hp.com, therbert@google.com, wsommerfeld@google.com,
	daniel.baluta@gmail.com, netdev@vger.kernel.org
Subject: Re: SO_REUSEPORT - can it be done in kernel?
Date: Tue, 01 Mar 2011 12:45:09 +0100	[thread overview]
Message-ID: <1298979909.3284.28.camel@edumazet-laptop> (raw)
In-Reply-To: <20110301112759.GK9763@canuck.infradead.org>

Le mardi 01 mars 2011 à 06:27 -0500, Thomas Graf a écrit :
> On Tue, Mar 01, 2011 at 12:13:04PM +0100, Eric Dumazet wrote:
> > Its a bit strange two cpus spend time in softirq, unless you have two
> > queryperf sources, and a multiqueue NIC, or maybe you use two NICS ?
> 
> one NIC, 2 clients (12 instances per client)
> 
> [root@hp-bl460cg7-01 ~]# cat /sys/class/net/eth0/queues/rx-0/rps_cpus 
> 00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000
> 
> [root@hp-bl460cg7-01 ~]# netstat -s | grep err
>     1781377 packet receive errors
> 
> > Mind use "perf top -C 1" and "perf top -C 11" to check what these cpus
> > do ?
> 

Thanks that's really interesting

> --------------------------------------------------------------------------------------------------------------------
>    PerfTop:   16198 irqs/sec  kernel:99.1%  exact:  0.0% [1000Hz cpu-clock-msecs],  (all, CPU: 1)
> --------------------------------------------------------------------------------------------------------------------
> 
>              samples  pcnt function                    DSO
>              _______ _____ ___________________________ ___________________________________________________________
> 

CPU 1 handles receives from your BENET NIC

(Its a bit strange, given this NIC should provide 4 rx queues). Load
could be split to two cpus in your case (two sources)

Try :

ethtool -S eth0 | grep rx_pk
     rxq0: rx_pkts: ??
     rxq1: rx_pkts: ??
     rxq2: rx_pkts: ??
     rxq3: rx_pkts: ??
     rxq4: rx_pkts: ??


Its BE_HDR_LEN being 64, small UDP frames are too big to fit in skb
head.




>             51675.00 33.2% _raw_spin_unlock_irqrestore [kernel.kallsyms]                                          
>             12426.00  8.0% clflush_cache_range         [kernel.kallsyms]                                          
>              5511.00  3.5% be_poll_rx                  /lib/modules/2.6.38-rc5+/kernel/drivers/net/benet/be2net.ko
>              4567.00  2.9% __udp4_lib_lookup           [kernel.kallsyms]                                          
>              3981.00  2.6% __kmalloc_node_track_caller [kernel.kallsyms]                                          
>              3975.00  2.6% get_rx_page_info            /lib/modules/2.6.38-rc5+/kernel/drivers/net/benet/be2net.ko
>              3725.00  2.4% sk_run_filter               [kernel.kallsyms]                                          
>              3606.00  2.3% get_page_from_freelist      [kernel.kallsyms]                                          
>              3178.00  2.0% __domain_mapping            [kernel.kallsyms]                                          
>              3122.00  2.0% kmem_cache_alloc_node       [kernel.kallsyms]                                          
>              2839.00  1.8% sock_queue_rcv_skb          [kernel.kallsyms]                                          
>              2246.00  1.4% __netif_receive_skb         [kernel.kallsyms]                                          
>              2245.00  1.4% nf_iterate                  [kernel.kallsyms]                                          
>              2081.00  1.3% __udp4_lib_rcv              [kernel.kallsyms]                                          
>              2042.00  1.3% ipt_do_table                [kernel.kallsyms]                                          
>              1901.00  1.2% _raw_spin_lock              [kernel.kallsyms]                                          
>              1856.00  1.2% __alloc_skb                 [kernel.kallsyms]                                          
>              1645.00  1.1% read_tsc                    [kernel.kallsyms]                                          
>              1562.00  1.0% nf_ct_tuple_equal           [kernel.kallsyms]                                          
>              1562.00  1.0% ip_rcv                      [kernel.kallsyms]                                          
>              1495.00  1.0% __nf_conntrack_find_get     [kernel.kallsyms]                                          
>              1477.00  0.9% sock_def_readable           [kernel.kallsyms]                                          
>              1363.00  0.9% find_first_bit              [kernel.kallsyms]                                          
>              1360.00  0.9% domain_get_iommu            [kernel.kallsyms]                                          
>              1255.00  0.8% udp_queue_rcv_skb           [kernel.kallsyms]                                          
>              1174.00  0.8% xfrm4_policy_check.clone.0  [kernel.kallsyms]                                          
>              1138.00  0.7% hash_conntrack_raw          [kernel.kallsyms]                                          
>              1000.00  0.6% intel_unmap_page            [kernel.kallsyms]                                          
>               959.00  0.6% load_pointer                [kernel.kallsyms]                                          
>               957.00  0.6% sock_flag                   [kernel.kallsyms]                                          
>               938.00  0.6% nf_conntrack_in             [kernel.kallsyms]                                          
>               891.00  0.6% _local_bh_enable_ip         [kernel.kallsyms]                                          
>               884.00  0.6% eth_type_trans              [kernel.kallsyms]                                          
>               832.00  0.5% be_post_rx_frags            /lib/modules/2.6.38-rc5+/kernel/drivers/net/benet/be2net.ko
>               829.00  0.5% __alloc_pages_nodemask      [kernel.kallsyms]                                          
>               813.00  0.5% kmem_cache_alloc            [kernel.kallsyms]                                          
>               802.00  0.5% netif_receive_skb           [kernel.kallsyms]                                          
>               802.00  0.5% ip_route_input_common       [kernel.kallsyms]                                          
>               723.00  0.5% nf_ct_get_tuple             [kernel.kallsyms]                                          
>               720.00  0.5% __intel_map_single          [kernel.kallsyms]                                          
>               720.00  0.5% udp_error                   [kernel.kallsyms]                                          
> 
> --------------------------------------------------------------------------------------------------------------------
>    PerfTop:   16360 irqs/sec  kernel:72.6%  exact:  0.0% [1000Hz cpu-clock-msecs],  (all, CPU: 11)
> --------------------------------------------------------------------------------------------------------------------
> 

CPU 11 handles all TX completions : Its a potential bottleneck.

I might ressurect XPS patch ;)

>              samples  pcnt function                      DSO
>              _______ _____ _____________________________ ___________________________________________________________
> 
>             16993.00 32.4% _raw_spin_unlock_irqrestore   [kernel.kallsyms]                                          
>              5833.00 11.1% clflush_cache_range           [kernel.kallsyms]                                          
>              3315.00  6.3% be_tx_compl_process           /lib/modules/2.6.38-rc5+/kernel/drivers/net/benet/be2net.ko
>              1818.00  3.5% kmem_cache_free               [kernel.kallsyms]                                          
>              1415.00  2.7% isc_rwlock_lock               /usr/lib64/libisc.so.62.0.1                                
>              1090.00  2.1% be_poll_tx_mcc                /lib/modules/2.6.38-rc5+/kernel/drivers/net/benet/be2net.ko
>               811.00  1.5% skb_release_head_state        [kernel.kallsyms]                                          
>               772.00  1.5% skb_release_data              [kernel.kallsyms]                                          
>               712.00  1.4% dns_rbt_findnode              /usr/lib64/libdns.so.69.0.1                                
>               703.00  1.3% isc_rwlock_unlock             /usr/lib64/libisc.so.62.0.1                                
>               695.00  1.3% dma_pte_clear_range           [kernel.kallsyms]                                          
>               618.00  1.2% kfree_skb                     [kernel.kallsyms]                                          
>               597.00  1.1% kfree                         [kernel.kallsyms]                                          
>               553.00  1.1% intel_unmap_page              [kernel.kallsyms]                                          
>               531.00  1.0% __do_softirq                  [kernel.kallsyms]                                          
>               504.00  1.0% isc_stats_increment           /usr/lib64/libisc.so.62.0.1                                
>               397.00  0.8% virt_to_head_page             [kernel.kallsyms]                                          
>               306.00  0.6% _raw_spin_lock                [kernel.kallsyms]                                          
>               270.00  0.5% domain_get_iommu              [kernel.kallsyms]                                          
>               256.00  0.5% dns_name_fullcompare          /usr/lib64/libdns.so.69.0.1                                
>               233.00  0.4% find_first_bit                [kernel.kallsyms]                                          
>               222.00  0.4% dns_name_equal                /usr/lib64/libdns.so.69.0.1                                
>               218.00  0.4% __pthread_mutex_lock_internal /lib64/libpthread-2.12.so                                  
>               207.00  0.4% dns_rbtnodechain_init         /usr/lib64/libdns.so.69.0.1                                
>               196.00  0.4% dns_acl_match                 /usr/lib64/libdns.so.69.0.1                                
>               194.00  0.4% dma_pte_free_pagetable        [kernel.kallsyms]                                          
>               192.00  0.4% dns_name_getlabelsequence     /usr/lib64/libdns.so.69.0.1                                
> 



  reply	other threads:[~2011-03-01 11:45 UTC|newest]

Thread overview: 91+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-01-27 10:07 SO_REUSEPORT - can it be done in kernel? Daniel Baluta
2011-01-27 15:55 ` Bill Sommerfeld
2011-01-27 21:32 ` Tom Herbert
2011-02-25 12:56   ` Thomas Graf
2011-02-25 19:18     ` Rick Jones
2011-02-25 19:20       ` David Miller
2011-02-26  0:57         ` Herbert Xu
2011-02-26  2:12           ` David Miller
2011-02-26  2:48             ` Herbert Xu
2011-02-26  3:07               ` David Miller
2011-02-26  3:11                 ` Herbert Xu
2011-02-26  7:31                   ` Eric Dumazet
2011-02-26  7:46                     ` David Miller
2011-02-27 11:02           ` Thomas Graf
2011-02-27 11:06             ` Herbert Xu
2011-02-28  3:45               ` Tom Herbert
2011-02-28  4:26                 ` Herbert Xu
2011-02-28 11:36               ` Herbert Xu
2011-02-28 13:32                 ` Eric Dumazet
2011-02-28 14:13                   ` Herbert Xu
2011-02-28 14:22                     ` Eric Dumazet
2011-02-28 14:25                       ` Herbert Xu
2011-02-28 14:53                   ` Eric Dumazet
2011-02-28 15:01                     ` Thomas Graf
2011-02-28 14:13                 ` Thomas Graf
2011-02-28 16:22                   ` Eric Dumazet
2011-02-28 16:37                     ` Thomas Graf
2011-02-28 17:07                       ` Eric Dumazet
2011-03-01 10:19                         ` Thomas Graf
2011-03-01 10:33                           ` Eric Dumazet
2011-03-01 11:07                             ` Thomas Graf
2011-03-01 11:13                               ` Eric Dumazet
2011-03-01 11:27                                 ` Thomas Graf
2011-03-01 11:45                                   ` Eric Dumazet [this message]
2011-03-01 11:53                                     ` Herbert Xu
2011-03-01 12:32                                       ` Herbert Xu
2011-03-01 13:04                                         ` Eric Dumazet
2011-03-01 13:11                                           ` Herbert Xu
2011-03-01 13:03                                       ` Eric Dumazet
2011-03-01 13:18                                         ` Herbert Xu
2011-03-01 13:52                                           ` Eric Dumazet
2011-03-01 13:58                                             ` Herbert Xu
2011-03-01 16:31                                           ` Eric Dumazet
2011-03-02  0:23                                             ` Herbert Xu
2011-03-02  2:00                                               ` Eric Dumazet
2011-03-02  2:39                                                 ` Herbert Xu
2011-03-02  2:56                                                   ` Eric Dumazet
2011-03-02  3:09                                                     ` Herbert Xu
2011-03-02  3:44                                                       ` Eric Dumazet
2011-03-02  7:12                                                   ` Tom Herbert
2011-03-02  7:31                                                     ` Herbert Xu
2011-03-02  8:04                                                       ` Eric Dumazet
2011-03-02  8:07                                                         ` Herbert Xu
2011-03-02  8:24                                                           ` Eric Dumazet
2011-03-01 12:01                                     ` Thomas Graf
2011-03-01 12:15                                       ` Herbert Xu
2011-03-01 13:27                                       ` Herbert Xu
2011-03-01 12:18                                     ` Thomas Graf
2011-03-01 12:19                                       ` Herbert Xu
2011-03-01 13:50                                         ` Thomas Graf
2011-03-01 14:06                                           ` Eric Dumazet
2011-03-01 14:22                                             ` Thomas Graf
2011-03-01 14:30                                               ` Thomas Graf
2011-03-01 14:52                                                 ` Eric Dumazet
2011-03-01 15:07                                                   ` Thomas Graf
2011-03-01  5:33                 ` Eric Dumazet
2011-03-01 12:35                 ` Herbert Xu
2011-03-01 12:36                   ` [PATCH 2/5] inet: Remove explicit write references to sk/inet in ip_append_data Herbert Xu
2011-03-02  6:15                     ` inet: Replace left-over references to inet->cork Herbert Xu
2011-03-02  7:01                       ` David Miller
2011-03-01 12:36                   ` [PATCH 3/5] inet: Add ip_make_skb and ip_finish_skb Herbert Xu
2011-03-01 12:36                   ` [PATCH 1/5] inet: Remove unused sk_sndmsg_* from UFO Herbert Xu
2011-03-01 12:36                   ` [PATCH 4/5] udp: Switch to ip_finish_skb Herbert Xu
2011-03-01 12:36                   ` [PATCH 5/5] udp: Add lockless transmit path Herbert Xu
2011-03-01 16:43                   ` SO_REUSEPORT - can it be done in kernel? Eric Dumazet
2011-03-01 20:36                     ` David Miller
2011-02-28 11:41               ` [PATCH 2/5] net: Remove explicit write references to sk/inet in ip_append_data Herbert Xu
2011-03-01  5:31                 ` Eric Dumazet
2011-02-28 11:41               ` [PATCH 1/5] net: Remove unused sk_sndmsg_* from UFO Herbert Xu
2011-03-01  5:31                 ` Eric Dumazet
2011-02-28 11:41               ` [PATCH 3/5] inet: Add ip_make_skb and ip_send_skb Herbert Xu
2011-03-01  5:31                 ` Eric Dumazet
2011-02-28 11:41               ` [PATCH 4/5] udp: Add lockless transmit path Herbert Xu
2011-02-28 11:41                 ` Herbert Xu
2011-03-01  5:30                 ` Eric Dumazet
2011-02-25 19:21       ` SO_REUSEPORT - can it be done in kernel? Eric Dumazet
2011-02-25 22:48       ` Thomas Graf
2011-02-25 23:15         ` Rick Jones
2011-02-25 19:51     ` Tom Herbert
2011-02-25 22:58       ` Thomas Graf
2011-02-25 23:33       ` Bill Sommerfeld

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