Iostat as below:
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util
sda 0.00 564.67 0.00 53.33 0.00 4944.00 92.70 0.03 0.47 0.15 0.80
nb0 0.00 0.00 0.00 8765.33 0.00 70122.67 8.00 144.72 16.48 0.11 100.00
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util
sda 0.00 585.33 0.00 51.00 0.00 5090.67 99.82 0.02 0.48 0.16 0.80
nb0 0.00 0.00 0.00 8716.67 0.00 69733.33 8.00 145.14 16.64 0.11 99.97
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util
sda 0.00 561.33 0.00 50.67 0.00 4896.00 96.63 0.01 0.24 0.09 0.47
nb0 0.00 0.00 0.00 8815.00 0.00 70520.00 8.00 145.25 16.51 0.11 100.00
In contrast to Centos64, the official kernel 2.6.32 doesn’t have this problem – it merges io requests into 100+ kB.
发件人: 刘海锋 [mailto:bjliuhaifeng@...1493...]
发送时间: 2014年2月13日 11:44
收件人: 'nbd-general@lists.sourceforge.net'
主题: NBD io request size is always 4KB on Centos6.4
Dear nbd maintainers/users,
Recently we found an annoying case: iostat shows the read/write IO requests from nbd are very small (always 4kB exactly without any merges) on Centos64.
And we tried tuning various kernel parameters but failed to solve it. Any suggestions?
Thank you all.
--haifeng
------------------------------------------------------------------------------
Android apps run on BlackBerry 10
Introducing the new BlackBerry 10.2.1 Runtime for Android apps.
Now with support for Jelly Bean, Bluetooth, Mapview and more.
Get your Android app in front of a whole new audience. Start now.
http://pubads.g.doubleclick.net/gampad/clk?id=124407151&iu=/4140/ostg.clktrk
_______________________________________________
Nbd-general mailing list
Nbd-general@...824...ceforge.net
https://lists.sourceforge.net/lists/listinfo/nbd-general