On Feb 6, 2011, at 11:55 AM, Zdenek Kaspar <zkaspar82@xxxxxxxxx> wrote: > Dne 6.2.2011 14:46, Justin Piszcz napsal(a): >> >> >> On Sun, 6 Feb 2011, Justin Piszcz wrote: >> >>> >>> >>> On Sat, 5 Feb 2011, Stan Hoeppner wrote: >>> >>>> Justin Piszcz put forth on 2/5/2011 7:08 PM: >>>> >> >> >> Hi, > > Hi, just few comments for maximal throughput.. > >> 1. Defaults below: >> sysctl -w net.core.wmem_max=131071 >> sysctl -w net.core.rmem_max=131071 >> sysctl -w net.core.wmem_default=118784 >> sysctl -w net.core.rmem_default=118784 >> sysctl -w net.core.optmem_max=20480 >> sysctl -w net.ipv4.igmp_max_memberships=20 >> sysctl -w net.ipv4.tcp_mem="379104 505472 758208" >> sysctl -w net.ipv4.tcp_wmem="4096 16384 4194304" >> sysctl -w net.ipv4.tcp_rmem="4096 87380 4194304" >> sysctl -w net.ipv4.udp_mem="379104 505472 758208" >> sysctl -w net.ipv4.udp_rmem_min=4096 >> sysctl -w net.ipv4.udp_wmem_min=4096 >> sysctl -w net.core.netdev_max_backlog=1024 > > sysctl net.ipv4.tcp_timestamps=0 > >> 2. Optimized settings, for > 800MiB/: >> >> # for 3ware raid, use 16384 readahead, > 16384 readahead, no improvement >> blockdev --setra 16384 /dev/sda > > elevator=deadline > >> # not sure if this helps much >> ethtool -K eth0 lro on > > Maybe try to _disable_ NIC offloads functions, sometimes its contra > productive (with enough CPU power, but I doubt on 2 socket box) + check > irqbalance.. > > If you have connection just between machines try the biggest possible MTU. > >> # seems to get performance > 600-700MiB/s faster >> sysctl -w net.core.wmem_max=4194304 >> sysctl -w net.core.rmem_max=4194304 >> sysctl -w net.core.wmem_default=4194304 >> sysctl -w net.core.rmem_default=4194304 >> sysctl -w net.core.optmem_max=20480 >> sysctl -w net.ipv4.igmp_max_memberships=20 >> sysctl -w net.ipv4.tcp_mem="4194304 4194304 4194304" >> sysctl -w net.ipv4.tcp_wmem="4194304 4194304 4194304" >> sysctl -w net.ipv4.tcp_rmem="4194304 4194304 4194304" >> sysctl -w net.ipv4.udp_mem="4194304 4194304 4194304" >> sysctl -w net.ipv4.udp_rmem_min=4096 >> sysctl -w net.ipv4.udp_wmem_min=4096 >> sysctl -w net.core.netdev_max_backlog=1048576 >> >> # the main option that makes all of the difference, the golden option >> # is the rszie and wsize of 1megabyte below: >> 10.0.1.4:/r1 /nfs/box2/r1 nfs >> tcp,bg,rw,hard,intr,nolock,nfsvers=3,rsize=1048576,wsize=1048576 0 0 >> >> CPU utilization: >> PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND >> 2069 root 20 0 18640 1304 688 R 91 0.0 0:15.50 cp >> 703 root 20 0 0 0 0 S 25 0.0 2:46.95 kswapd0 >> >> With a single copy I get roughly 700-800MiB/s: >> >> Device eth0 [10.0.1.3] (1/1): >> ================================================================================ >> >> Incoming: >> ###################### #################### #### >> ###################### #################### #### >> ###################### #################### #### >> ###################### #################### #### >> ###################### #################### #### >> ###################### #################### #### Curr: 808.71 MByte/s >> ###################### #################### #### Avg: 706.11 MByte/s >> ###################### #################### #### Min: 0.00 MByte/s >> ###################### #################### #### Max: 860.17 MByte/s >> ###################### #################### #### Ttl: 344.70 GByte >> >> With two copies I get up to 830-850MiB/s: >> >> Device eth0 [10.0.1.3] (1/1): >> ================================================================================ >> >> Incoming: >> ############################################ #### >> ############################################ #### >> ############################################ #### >> ############################################ #### >> ############################################ #### >> ############################################ #### Curr: 846.61 MByte/s >> ############################################ #### Avg: 683.14 MByte/s >> ############################################ #### Min: 0.00 MByte/s >> ############################################ #### Max: 860.17 MByte/s >> ############################################ #### Ttl: 305.71 GByte >> >> Using a 4MiB r/w size with NFS improves performance to sustain > 750MiB/s >> a little better I think: >> 10.0.1.4:/r1 /nfs/box2/r1 nfs >> tcp,bg,rw,hard,intr,nolock,nfsvers=3,rsize=4194304,wsize=4194304 0 > > What about using UDP ? > >> Anyhow, roughly 750-850MiB/s it would be nice to get 1Gbyte/sec but I guess >> the kerrnel (or my HW, CPU not fast enough) is not there yet. >> >> Also found a good doc from RedHat: >> http://www.redhat.com/promo/summit/2008/downloads/pdf/Thursday/Mark_Wagner.pdf >> >> >> Justin. >> > > HTH, Z. Thx for suggestions, I have tried some of those additional optimizations in the past but they did not seem to give increases in performance, but will revisit them if I have time, thanks. UDP seemed to hit and stay at 650MiB/s. Justin. -- To unsubscribe from this list: send the line "unsubscribe linux-net" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
