Questions tagged [iostat]
The iostat tag has no usage guidance.
24
questions with no upvoted or accepted answers
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Can iostat output show mismatched read data for mdadm raid5 array?
I'm trying to understand this iostat output:
tps kB_read/s kB_wrtn/s kB_dscd/s kB_read kB_wrtn kB_dscd Device
500.30 58.9M 19.4k 0.0k 329.1G ...
- 109
3
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0
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897
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Why are /proc/diskstats figures suddenly unbelievably low?
I have a Debian jessie server with two Intel DC S3610 SSDs in it, in RAID-10. It's reasonably busy for IO and for the last several weeks I've been graphing the IOPS:
As you can see, most of the time ...
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2
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1k
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iotune qemu/KVM total_iops total_bytes limits
I have created some qemu/KVM virtual machines on SSDs.
The host has ~6 SSDs. 1 is being used for the OS, and each of the other SSDs has two VM guests.
I'm using iotune to limit the capabilities of ...
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2
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153
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Resetting disk table in zfs pool
In Our Solaris 11.3 zfs storage server, one disk in the pool died, we replaced it. Everything is working fine, but iostat is still showing old disk with large error count. This is bothering our ...
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2
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2
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283
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physical vs logical disk transactions
I'm trying to analyze server requirements for a set of virtual machines. We're using LVM on them, so iostat shows numbers for both the logical volume and the physical disk, and they often don't match ...
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1
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1
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437
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why iostat not showing one of my disk?
Please check the picture below. The df shows /dev/xsda mounted
But iostat not showing the device. Why?
[admin] /dev]$df -h | grep '/dev'
tmpfs 64M 0 64M 0% /dev
/dev/nvme1n1 7.0T ...
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1
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0
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772
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How does avgqu-sz size in iostat output relate to r_await and w_await?
Can someone explain what does avgqu-sz mean in the output of iostat? The manual page states like this.
avgqu-sz:
The average queue length of the requests that were issued to the device.
Can ...
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1
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0
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294
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Difference in utilisation reported by iostat for two identical disks in RAID1
I'm trying to debug some weird behaviour with Postgres performance and am trying to understand the iostat output. I'm on 2x SSD on RAID1. Why would one of the disks be reported at ~21% utilisation ...
- 539
1
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1
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2k
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What does iostat show a different utilization for the 'dm' device?
I installed an M.2 drive into a Proxmox host this morning and monitored the disks with iostat -x 1. Why is iostat showing dm-7 is at 98% utilization, while the M.2 LVM PV (nvme0n1p1) shows only 6.8?
...
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1
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1
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What are the parameters in iostat
I used iostat and trying to understand the iostat output using this link : https://linoxide.com/linux-command/linux-iostat-command/ but It is not clearly explained.
PF the output at different times ...
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1
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1
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988
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NFS read/writes since startup
I'd like to retrieve the total number of kilobytes read/written for each NFS mount point.
Using the following commands, I'm able to see the current throughput for each NFS mount point in kB/S.
...
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1
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0
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669
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MySql/RedHat, High I/O Wait ... for a few hours... then disappears
I've got a RH server as a VMWare instance logging GPS fixes 24x7. The transaction volume hasn't changed over the months (in fact I am pruning the transaction table more aggressively now) with only ...
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rhel + disk util is very high , what is the impact for long term
we have backup server with rhel version 7.2
server is VM machine , and OS disk is VMDK disk
disk used space is around - 50% , and from smartctl we not see problem
as we can see from follwing details
...
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0
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167
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Needs to identify cause of high load average
I see high kB_read in iostat output. right now, load average of the system is very high. Is it io bound high load?
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System performance of Rasperry Pi (running k8s) is very poor - how to debug?
Summary
I'm running a slim homelab (Kubernetes cluster with few pods, Gitea, Drone, Docker Registry, and NFS share) on a 2-Pi4 cluster, and the system performance is poor. I've noted that the ...
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High util iostat
I have server with oracle db. It works on Dell Unity storage.
The server has very slow disk IO.
How can I fix it?
Here are some details of my server:
OS - OL8
Kernel - 5.4.17 uek
Storage - Dell ...
- 1
0
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0
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486
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High I/O wait in apache tomcat server
Facing high I/O wait in apache tomcat server when the load increases.
Suspecting disk I/O is less when tomcat is running however. disk IO seems drops drastically when tomcat is running along with the ...
0
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2
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339
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How to determine if I/O is slow for server
I have used I/O stat to check whether my server's I/O is slow or not. The % util is high but so is the read/sec - write/sec. Can anyone help ?
Following is the output of iostat -mx command
Linux 2.6....
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1
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1k
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How to get gcc installed on CoreOS hostmachine rather than the containers running inside it
I have an external monitoring tool that connects over ssh periodically and checks the various system params of a linux box (cpu, mem, etc.). However this approach does not work with CoreOS since it ...
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163
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Nagios php script to read iostat values
I'm working on a php script(nagios plugin) to read r/s,w/s,rMB/s,wMB/s,%util from the iostat command, e.g.
#iostat -xm sda
avg-cpu: %user %nice %system %iowait %steal %idle
1.05 0....
user387821
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No w/s in iostat output even though wMB/s is high
I am trying to format a 2 TB SAN based block device (/dev/mapper/mpathb). Even though, mke2fs has been running since over one hour without completing, iostat -z -x -m 10 output in a separate terminal ...
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High cancelled_write_bytes, high IO load, concurrent memory-mapping
I have a software for persisting/retrieving data from files (a bit like database, but it's not exactly a database engine). It's not open source and the documentation is sparse, therefore I don't have ...
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784
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how can I tell if there is a cpu trashing on my linux machine
I want to write a script that will kill my processes when my machine is doing "too much" swapping of process memory from disk to memory.
What is the best way to determine that? I saw top has %wa and ...
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0
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1
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1k
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SNMP monitoring of iostat on a Solaris 10 server?
I'm looking at the System Management Agent resources which gives guidance to the Solaris SNMP tools however after extensive googling I can't find any OID reference list or details on what can be ...
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