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Questions tagged [iostat]

iostat displays the current CPU load average and disk I/O information.

iostat (input/output statistics) is a computer system monitor tool used to collect and show operating system storage input and output statistics.

The iostat command is used for monitoring system input/output device loading by observing the time the devices are active in relation to their average transfer rates. The iostat command generates reports that can be used to change system configuration to better balance the input/output load between physical disks.

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Perl - kill ongoing process launched from a pipe

My goal is to launch an ongoing process (such as iostat) and parse some information. Once I am done, I would like to kill iostat and gracefully close the pipe. Remember, iostat will run forever until I kill it. If I try to kill the process before…
sandro
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How to Interpret I/O on ksar, sar

Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util sda 0.01 1.38 0.02 0.51 0.37 7.56 29.42 0.02 31.72 6.15 0.33 sda1 0.00 0.00 0.00 0.00…
flyclassic
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dtrace scripts io counters per NFS mount

I need to measure performance counters per NFS mount I have on my Nexenta machine (Based on OpenSolaris). iostat is great, the problem is that it count by devices and not at the NFS level. Is there any way I can do that with a dtrace…
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testing sequential disk write performance with fio and iostat

I am trying to make sense of sequential disk write performance on a spinning hard disk. I am using direct and sync io to bypass the page cache. For small block size (4KB) fio reports an iops of ~11. So this means fio is issuing 11 write system…
sha
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How to convert output of iostat command to json

I need to convert the output of iostat command to json. Information is needed only for sd[a-z] discs. It is advisable to do the conversion using awk. iostat -xd Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz …
xasik
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iostats shows more writes for logical volume than for physical volume under it

I have a server where iostat shows weird numbers to me: avg-cpu: %user %nice %system %iowait %steal %idle 22.5% 0.0% 0.8% 1.3% 0.0% 75.5% Device tps kB_read/s kB_wrtn/s kB_read kB_wrtn loop0 …
Dmitry Maslennikov
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awk + can't cut the field from iostat

when I do the follwing , then we get output iostat -x 1|grep sdb sdb 0.00 13.65 4.17 11.65 113.72 991.55 139.74 0.24 15.39 3.27 19.73 0.46 0.72 sdb 0.00 0.00 0.00 0.00 0.00 …
jessica
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Write IO breakups on linux?

My application is using O_DIRECT for flushing 2MB worth of data directly to a 3-way-stripe storage (mounted as an lvm volume).. I am getting a very pathetic write speed on this storage. The iostat shows that the large request size is being broken…
Hemanshu
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How to calculate the throughput usage of AWS EBS volume

We have a hadoop cluster running on AWS EC2 instances. Configured 16T st1 volume in datanodes for HDFS usage. We need to understand, what is the maximum throughput we are hitting on this st1 volumes. Since CloudWatch is covering data on 5 mins…
sajesh pp
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Why is the iops observed by fio different from that observed by iostat?

Recently, I'm trying to test my disk using fio. My configuration of fio is as follows: [global] invalidate=0 #…
Rainman1985
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How to get iostat second sample

iostat -x doesn't show the real values. That is obvious if you run iostat -x 1 and see the values per second. When I run iostat -x 1 2 I thought that I can get the values that I wanted by grabbing the exact lines and then the values. iostat -x 1 2…
jimakos17
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How to remove repeated header from the output of iostat linux command

I am running following command and getting following output which I am saving into file. sysstat/iostat -mdt sda1 1 >> /tmp/disk.out & Outout is following Linux 3.16.0-25-generic (bscpower8n2) 09/25/2016 _ppc64le_ (192 CPU) 09/25/2016…
David
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FreeBSD iostat - How to tell if there's a problem?

I run a FreeBSD NFS server and recently I've been having odd issues throughout the cluster (the Apache servers are hanging in "lockf" state when loading files from the NFS share, etc). I'm fairly new to this, so my question is how can I tell if a…
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Programmatically get OSX Fusion Drive information

I'm working on a project that links drives (and their associated stats, such as those displayed by iostat) and partitions to mount points, but running into issues with the way OS X does the Fusion Drive. I have been able to gather information on…
Daniel Widdis
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Disk stats in solaris

I am looking for a "cat /proc/diskstats (from linux)" equivalent in solaris OS, to get disk stats such as reads per sec, writes per sec, kb reads per sec, kb writes per sec. I tried iostat -xnp, but i guess its not giving me the complete…
Venkat Teki
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