{"id":11285,"date":"2019-03-12T22:07:13","date_gmt":"2019-03-12T22:07:13","guid":{"rendered":"http:\/\/www.appservgrid.com\/paw92\/?p=11285"},"modified":"2019-03-12T22:07:13","modified_gmt":"2019-03-12T22:07:13","slug":"linux-performance-monitoring-with-vmstat-and-iostat-commands","status":"publish","type":"post","link":"https:\/\/www.appservgrid.com\/paw92\/index.php\/2019\/03\/12\/linux-performance-monitoring-with-vmstat-and-iostat-commands\/","title":{"rendered":"Linux Performance Monitoring with Vmstat and Iostat Commands"},"content":{"rendered":"

This is our on-going series of commands and performance monitoring in\u00a0Linux<\/strong>.\u00a0Vmstat<\/strong>\u00a0and\u00a0Iostat<\/strong>\u00a0both commands are available on all major\u00a0Unix-like<\/strong>\u00a0(Linux\/Unix\/FreeBSD\/Solaris<\/strong>) Operating Systems.<\/p>\n

If\u00a0vmstat<\/strong>\u00a0and\u00a0iostat<\/strong>\u00a0commands are not available on your box, please install\u00a0sysstat<\/strong>\u00a0package. The\u00a0vmstat<\/strong>,\u00a0sar<\/strong>and\u00a0iostat<\/strong>\u00a0commands are the collection of package included in\u00a0sysstat<\/strong>\u00a0\u2013 the system monitoring tools. The\u00a0iostat<\/strong>\u00a0generates reports of\u00a0CPU<\/strong>\u00a0& all device statistics. You may download and install\u00a0sysstat<\/strong>\u00a0using source tarball from link\u00a0sysstat<\/a>, but we recommend installing through\u00a0YUM<\/strong>\u00a0command.<\/p>\n

\n

\"Linux<\/a><\/p>\n

Linux Performance Monitoring with Vmstat and Iostat<\/p>\n<\/div>\n

Install Sysstat in Linux<\/h4>\n
# yum -y install sysstat<\/pre>\n
    \n
  1. vmstat<\/strong>\u00a0\u2013 Summary information of\u00a0Memory<\/strong>,\u00a0Processes<\/strong>,\u00a0Paging<\/strong>\u00a0etc.<\/li>\n
  2. iostat<\/strong>\u00a0\u2013 Central Processing Unit (CPU<\/strong>) statistics and\u00a0input\/output<\/strong>\u00a0statistics for\u00a0devices<\/strong>\u00a0and\u00a0partitions<\/strong>.<\/li>\n<\/ol>\n
    6 Vmstat Command Examples in Linux<\/strong><\/div>\n
    1. List Active and Inactive Memory<\/h4>\n
    In the below example, there are six columns. The significant of the columns are explained in man page of\u00a0vmstat<\/strong>\u00a0in details. Most important fields are\u00a0free<\/strong>\u00a0under memory and\u00a0si, so<\/strong>\u00a0under swap column.<\/p>\n
    [root@tecmint ~]# vmstat -a<\/strong>\r\n\r\nprocs -----------memory---------- ---swap-- -----io---- --system-- -----cpu-----\r\n r  b   swpd   free  inact active   si   so    bi    bo   in   cs us sy id wa st\r\n 1  0      0 810420  97380  70628    0    0   115     4   89   79  1  6 90  3  0<\/pre>\n
      \n
    1. \n
        \n
      1. Free<\/strong>\u00a0\u2013 Amount of free\/idle memory spaces.<\/li>\n
      2. si<\/strong>\u00a0\u2013 Swaped in every second from disk in Kilo Bytes.<\/li>\n
      3. so<\/strong>\u00a0\u2013 Swaped out every second to disk in Kilo Bytes.<\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
        Note:<\/strong>\u00a0If you run\u00a0vmstat<\/strong>\u00a0without parameters it\u2019ll displays summary report since system boot.<\/p>\n
        2. Execute vmstat \u2018X\u2019 seconds and (\u2018N\u2019number of times)<\/h4>\n
        With this command,\u00a0vmstat<\/strong>\u00a0execute every two seconds and stop automatically after executing six intervals.<\/p>\n
        [root@tecmint ~]# vmstat 2 6<\/strong>\r\n\r\nprocs -----------memory---------- ---swap-- -----io---- --system-- -----cpu-----\r\n r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st\r\n 0  0      0 810420  22064 101368    0    0    56     3   50   57  0  3 95  2  0\r\n 0  0      0 810412  22064 101368    0    0     0     0   16   35  0  0 100  0  0\r\n 0  0      0 810412  22064 101368    0    0     0     0   14   35  0  0 100  0  0\r\n 0  0      0 810412  22064 101368    0    0     0     0   17   38  0  0 100  0  0\r\n 0  0      0 810412  22064 101368    0    0     0     0   17   35  0  0 100  0  0\r\n 0  0      0 810412  22064 101368    0    0     0     0   18   36  0  1 100  0  0<\/pre>\n
        3. Vmstat with timestamps<\/h4>\n
        vmstat<\/strong>\u00a0command with\u00a0-t<\/strong>\u00a0parameter shows timestamps with every line printed as shown below.<\/p>\n
        [tecmint@tecmint ~]$ vmstat -t 1 5<\/strong>\r\n\r\nprocs -----------memory---------- ---swap-- -----io---- --system-- -----cpu------ ---timestamp---\r\n r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st\r\n 0  0      0 632028  24992 192244    0    0    70     5   55   78  1  3 95  1  0        2012-09-02 14:57:18 IST\r\n 1  0      0 632028  24992 192244    0    0     0     0  171  514  1  5 94  0  0        2012-09-02 14:57:19 IST\r\n 1  0      0 631904  24992 192244    0    0     0     0  195  600  0  5 95  0  0        2012-09-02 14:57:20 IST\r\n 0  0      0 631780  24992 192244    0    0     0     0  156  524  0  5 95  0  0        2012-09-02 14:57:21 IST\r\n 1  0      0 631656  24992 192244    0    0     0     0  189  592  0  5 95  0  0        2012-09-02 14:57:22 IST<\/pre>\n
        4. Statistics of Various Counter<\/h4>\n
        vmstat<\/strong>\u00a0command and\u00a0-s<\/strong>\u00a0switch displays summary of various event counters and memory statistics.<\/p>\n
        [tecmint@tecmint ~]$ vmstat -s<\/strong>\r\n\r\n      1030800  total memory\r\n       524656  used memory\r\n       277784  active memory\r\n       185920  inactive memory\r\n       506144  free memory\r\n        26864  buffer memory\r\n       310104  swap cache\r\n      2064376  total swap\r\n            0  used swap\r\n      2064376  free swap\r\n         4539 non-nice user cpu ticks\r\n            0 nice user cpu ticks\r\n        11569 system cpu ticks\r\n       329608 idle cpu ticks\r\n         5012 IO-wait cpu ticks\r\n           79 IRQ cpu ticks\r\n           74 softirq cpu ticks\r\n            0 stolen cpu ticks\r\n       336038 pages paged in\r\n        67945 pages paged out\r\n            0 pages swapped in\r\n            0 pages swapped out\r\n       258526 interrupts\r\n       392439 CPU context switches\r\n   1346574857 boot time\r\n         2309 forks<\/pre>\n
        5. Disks Statistics<\/h4>\n
        vmstat<\/strong>\u00a0with\u00a0-d<\/strong>\u00a0option display all disks statistics.<\/p>\n
        [tecmint@tecmint ~]$ vmstat -d<\/strong>\r\n\r\ndisk- ------------reads------------ ------------writes----------- -----IO------\r\n       total merged sectors      ms  total merged sectors      ms    cur    sec\r\nram0       0      0       0       0      0      0       0       0      0      0\r\nram1       0      0       0       0      0      0       0       0      0      0\r\nram2       0      0       0       0      0      0       0       0      0      0\r\nram3       0      0       0       0      0      0       0       0      0      0\r\nram4       0      0       0       0      0      0       0       0      0      0\r\nram5       0      0       0       0      0      0       0       0      0      0\r\nram6       0      0       0       0      0      0       0       0      0      0\r\nram7       0      0       0       0      0      0       0       0      0      0\r\nram8       0      0       0       0      0      0       0       0      0      0\r\nram9       0      0       0       0      0      0       0       0      0      0\r\nram10      0      0       0       0      0      0       0       0      0      0\r\nram11      0      0       0       0      0      0       0       0      0      0\r\nram12      0      0       0       0      0      0       0       0      0      0\r\nram13      0      0       0       0      0      0       0       0      0      0\r\nram14      0      0       0       0      0      0       0       0      0      0\r\nram15      0      0       0       0      0      0       0       0      0      0\r\nloop0      0      0       0       0      0      0       0       0      0      0\r\nloop1      0      0       0       0      0      0       0       0      0      0\r\nloop2      0      0       0       0      0      0       0       0      0      0\r\nloop3      0      0       0       0      0      0       0       0      0      0\r\nloop4      0      0       0       0      0      0       0       0      0      0\r\nloop5      0      0       0       0      0      0       0       0      0      0\r\nloop6      0      0       0       0      0      0       0       0      0      0\r\nloop7      0      0       0       0      0      0       0       0      0      0\r\nsr0        0      0       0       0      0      0       0       0      0      0\r\nsda     7712   5145  668732  409619   3282  28884  257402  644566      0    126\r\ndm-0   11578      0  659242 1113017  32163      0  257384 8460026      0    126\r\ndm-1     324      0    2592    3845      0      0       0       0      0      2<\/pre>\n
        6. Display Statistics in Megabytes<\/h4>\n
        The\u00a0vmstat<\/strong>\u00a0displays in\u00a0Megabytes<\/strong>\u00a0with parameters\u00a0-S<\/strong>\u00a0and\u00a0M<\/strong>(Uppercase & megabytes). By default\u00a0vmstat<\/strong>displays statistics in kilobytes.<\/p>\n
        [root@tecmint ~]# vmstat -S M 1 5<\/strong>\r\n\r\nprocs -----------memory---------- ---swap-- -----io---- --system-- -----cpu-----\r\n r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st\r\n 0  0      0    346     53    476    0    0    95     8   42   55  0  2 96  2  0\r\n 0  0      0    346     53    476    0    0     0     0   12   15  0  0 100  0  0\r\n 0  0      0    346     53    476    0    0     0     0   32   62  0  0 100  0  0\r\n 0  0      0    346     53    476    0    0     0     0   15   13  0  0 100  0  0\r\n 0  0      0    346     53    476    0    0     0     0   34   61  0  1 99  0  0<\/pre>\n
        6 Iostat Command Examples in Linux<\/strong><\/div>\n
        7. Display CPU and I\/O statistics<\/h4>\n
        iostat<\/strong>\u00a0without arguments displays\u00a0CPU<\/strong>\u00a0and\u00a0I\/O<\/strong>\u00a0statistics of all partitions as shown below.<\/p>\n
        [root@tecmint ~]# iostat<\/strong>\r\n\r\nLinux 2.6.32-279.el6.i686 (tecmint.com)         09\/03\/2012      _i686_  (1 CPU)\r\n\r\navg-cpu:  %user   %nice %system %iowait  %steal   %idle\r\n           0.12    0.01    1.54    2.08    0.00   96.24\r\n\r\nDevice:            tps   Blk_read\/s   Blk_wrtn\/s   Blk_read   Blk_wrtn\r\nsda               3.59       161.02        13.48    1086002      90882\r\ndm-0              5.76       159.71        13.47    1077154      90864\r\ndm-1              0.05         0.38         0.00       2576          0<\/pre>\n
        8. Shows only CPU Statistics<\/h4>\n
        iostat<\/strong>\u00a0with\u00a0-c<\/strong>\u00a0arguments displays only\u00a0CPU<\/strong>\u00a0statistics as shown below.<\/p>\n
        [root@tecmint ~]# iostat -c<\/strong>\r\n\r\nLinux 2.6.32-279.el6.i686 (tecmint.com)         09\/03\/2012      _i686_  (1 CPU)\r\n\r\navg-cpu:  %user   %nice %system %iowait  %steal   %idle\r\n           0.12    0.01    1.47    1.98    0.00   96.42<\/pre>\n
        9. Shows only Disks I\/O Statistics<\/h4>\n
        iostat<\/strong>\u00a0with\u00a0-d<\/strong>\u00a0arguments displays only disks\u00a0I\/O<\/strong>\u00a0statistics of all partitions as shown.<\/p>\n
        [root@tecmint ~]# iostat -d<\/strong>\r\n\r\nLinux 2.6.32-279.el6.i686 (tecmint.com)         09\/03\/2012      _i686_  (1 CPU)\r\n\r\nDevice:            tps   Blk_read\/s   Blk_wrtn\/s   Blk_read   Blk_wrtn\r\nsda               3.35       149.81        12.66    1086002      91746\r\ndm-0              5.37       148.59        12.65    1077154      91728\r\ndm-1              0.04         0.36         0.00       2576          0<\/pre>\n
        10. Shows I\/O statistics only of a single device.<\/h4>\n
        By default it displays statistics of all partitions, with\u00a0-p<\/strong>\u00a0and device name arguments displays only disks\u00a0I\/O<\/strong>statistics for specific device only as shown.<\/p>\n
        [root@tecmint ~]# iostat -p sda<\/strong>\r\n\r\nLinux 2.6.32-279.el6.i686 (tecmint.com)         09\/03\/2012      _i686_  (1 CPU)\r\n\r\navg-cpu:  %user   %nice %system %iowait  %steal   %idle\r\n           0.11    0.01    1.44    1.92    0.00   96.52\r\n\r\nDevice:            tps   Blk_read\/s   Blk_wrtn\/s   Blk_read   Blk_wrtn\r\nsda               3.32       148.52        12.55    1086002      91770\r\nsda1              0.07         0.56         0.00       4120         18\r\nsda2              3.22       147.79        12.55    1080650      91752<\/pre>\n
        11. Display LVM Statistics<\/h4>\n
        With\u00a0-N<\/strong>\u00a0(Uppercase) parameter displays only\u00a0LVM<\/strong>\u00a0statistics as shown.<\/p>\n
        [root@tecmint ~]# iostat -N<\/strong>\r\n\r\nLinux 2.6.32-279.el6.i686 (tecmint.com)         09\/03\/2012      _i686_  (1 CPU)\r\n\r\navg-cpu:  %user   %nice %system %iowait  %steal   %idle\r\n           0.11    0.01    1.39    1.85    0.00   96.64\r\n\r\nDevice:            tps   Blk_read\/s   Blk_wrtn\/s   Blk_read   Blk_wrtn\r\nsda               3.20       142.84        12.16    1086002      92466\r\nvg_tecmint-lv_root     5.13       141.68        12.16    1077154      92448\r\nvg_tecmint-lv_swap     0.04         0.34         0.00       2576          0<\/pre>\n
        12. iostat version.<\/h4>\n
        With\u00a0-V<\/strong>\u00a0(Uppercase) parameter displays version of\u00a0iostat<\/strong>\u00a0as shown.<\/p>\n
        [root@tecmint ~]# iostat -V<\/strong>\r\n\r\nsysstat version 9.0.4\r\n(C) Sebastien Godard (sysstat  orange.fr)<\/pre>\n
        Note: vmstat<\/strong>\u00a0and\u00a0iostat<\/strong>\u00a0contains number of columns and flags which may not possible to explain in details. If you want to know more about it you may refer man page of\u00a0vmstat<\/strong>\u00a0and\u00a0iostat<\/strong>. Please share it if you find this article is useful through our comment box below.<\/p>\n
        Source<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
        This is our on-going series of commands and performance monitoring in\u00a0Linux.\u00a0Vmstat\u00a0and\u00a0Iostat\u00a0both commands are available on all major\u00a0Unix-like\u00a0(Linux\/Unix\/FreeBSD\/Solaris) Operating Systems. If\u00a0vmstat\u00a0and\u00a0iostat\u00a0commands are not available on your box, please install\u00a0sysstat\u00a0package. The\u00a0vmstat,\u00a0sarand\u00a0iostat\u00a0commands are the collection of package included in\u00a0sysstat\u00a0\u2013 the system monitoring tools. The\u00a0iostat\u00a0generates reports of\u00a0CPU\u00a0& all device statistics. You may download and install\u00a0sysstat\u00a0using source tarball from link\u00a0sysstat, … <\/p>\n
        Continue reading “Linux Performance Monitoring with Vmstat and Iostat Commands”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-11285","post","type-post","status-publish","format-standard","hentry","category-linux"],"_links":{"self":[{"href":"https:\/\/www.appservgrid.com\/paw92\/index.php\/wp-json\/wp\/v2\/posts\/11285","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.appservgrid.com\/paw92\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.appservgrid.com\/paw92\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.appservgrid.com\/paw92\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.appservgrid.com\/paw92\/index.php\/wp-json\/wp\/v2\/comments?post=11285"}],"version-history":[{"count":1,"href":"https:\/\/www.appservgrid.com\/paw92\/index.php\/wp-json\/wp\/v2\/posts\/11285\/revisions"}],"predecessor-version":[{"id":11286,"href":"https:\/\/www.appservgrid.com\/paw92\/index.php\/wp-json\/wp\/v2\/posts\/11285\/revisions\/11286"}],"wp:attachment":[{"href":"https:\/\/www.appservgrid.com\/paw92\/index.php\/wp-json\/wp\/v2\/media?parent=11285"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.appservgrid.com\/paw92\/index.php\/wp-json\/wp\/v2\/categories?post=11285"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.appservgrid.com\/paw92\/index.php\/wp-json\/wp\/v2\/tags?post=11285"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}