Questions tagged [io]
I/O refers to "Input/Output" generally being a synonym to Write/Read in terms of a file.
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What could cause input/output errors after resuming from sleep mode?
For a few weeks now I experience IO errors when I reopen my Ubuntu (22.04) laptop. Then I can only hold down the power button and hard reset everything. I will gladly provide you with necessary ...
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Why can I write to /dev/ttys010 using `>` but not `|` [duplicate]
I am trying to play around and understanding ttys.
In one terminal emulator window, the output of tty gives me
$ tty
/dev/ttys010
So I figured if I write to this device, the terminal window will show ...
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How to limit tar process to not utilize IO at max?
So I have a server where I have important processes running 24/7, and once per day I run a backup of a specific folder like this:
time tar cf ${HOME}/${SNAP_NAME} -C ${DATA_PATH} . &>>${...
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Change the scheduler
I have made my kernel-module which is a scheduler and i want to use it. My scheduler is team29682972_kyber. I run the command insmod. Then cat /sys/block/sda/queue/scheduler. I have :
[mq-deadline] ...
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Ubuntu 20.04, SSD utilization is too high with iostat. But the read speed is low
I am training deep learning models with pytorch, Ubuntu 20.04. But the io performance with the ssd is strange. When I start training, the training speed is full in whole day. But it sometime slows ...
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NVMe slow write speed capped at 513,2 MB/s
Hello just bought a Samsung 980 Pro to be used with a fast camera.
I put it in a system with a X570-A-PRO mobo (On the M2_1 socket) and a Ryzen 9 5950x. I am running on the 22.4 with the 5.15.0-48 ...
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berkeley socket programming issues - <netinet.h> not found
My standard socket stuff doesnt work anymore on Ubuntu 20.04.4 - <netinet.h> not found. This then leads to definition errors of sockaddr.
s.c:22:14: error: ‘struct sockaddr’ has no member named ‘...
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System freezing on disk I/O
I am facing a similar (maybe the same problem) reported by System freezes on disk I/O . This problem also occurred with the first release of Fedora 36.
When I start a process a little more disk I/O ...
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Why is the read/write speed of two SSDs so slow when mounted as single logical volume with LVM under Ubuntu 18.04 LTS?
For scientific computing, we need fast read/write speeds. So I upgraded one of our machines with 2 SSDs. I used the command
hdparm -Tt /dev/sda
to test the read speed. As reference, our standard HDDs ...
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Ubuntu 20.04 LTS stopped working overnight. I/O error and COMRESET failed (errno=-16)
Yesterday night, I installed Ubuntu, it was working fine that night. Today morning I opened my laptop for my class, it was working fine, but after some time my class got struck. And it opened CLI(...
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How compare several directories' data transfer (read/write) for defined periods?
With interest for the amount of data transfered to or from several directories (including sub directories) it occured, that there is lack of tooling for this special task.
For low level integration, ...
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Is there any non-root disk IO monitor software available on Ubuntu?
Is there any disk IO monitor software available on Ubuntu that can show what processes are reading/writing at what speed and that I can install and run without sudo?
I know there is iotop, but I can't ...
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Disk writes suddenly very slow. SMART tests all report normal
I noticed that my Ubuntu workstation has become extremely slow when writing to disk. I have two hard drives, one NVME and the other SSD (both set up with ZFS). They should be able to sustain multi-GB/...
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Ubuntu 20.04.3 with issues in Acer Nitro 5 with Ryzen 7 (Lagging/freezing UI response to I/O, lid closing behavior)
I've recently bought an Acer Nitro 5 laptop with AMD Ryzen 7 4800H and GTX 1650Ti,that came with Windows 10 as its operating system, and installed Ubuntu 20.04.3 to it, in a dual boot configuration. ...
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No such file or directory using I/O redirection
I am using I/O redirection in Linux to take input from a file named input.txt and output the results to output.txt.
The command:
/home/gajeet/Documents/OpenSource/Test < input.txt > output.txt
...
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Trying to fix front i/o headphone out overriding audio line out
I just started running Ubuntu 20.04, MATE 1.24.0 on my desktop. my case has a front i/o with audio out and microphone in, and I typically use these for my razer headset with a headset/microphone ...
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Ubuntu 21.04 freezes with i/o errors, fsck and smartctl does not show errors
I am seeing this on a Lenovo Flex 5-14. Ubuntu is freezing with message saying the filesystem is not writeable.
I tried fsck and smartctl. Neither showed any errors. I have dual boot and Windows 10 ...
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Redirect output with '>&!'
I know that >& means redirect stderr to stdout.
But I don't know the meaning of >&!, I tried following command but it seems like normal.
Example:
cat xxx.txt >&! xxx.output
My ...
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How to enable blkmq for NVMe devices?
Ubuntu: 20.10-desktop
kernel: 5.8.0-40-generic
Device: Samsung 980 pro 500G
$ cat /sys/block/nvme1n1/queue/scheduler
[none] mq-deadline
Does it means I am using the "Linux I/O scheduler" ...
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Fresh Lubuntu 20.04.5 - Continuous HDD I/O operations while in idle
Freshly installed Lubuntu 20.04, with no software installed, HDD makes an abrupt sound every 2-5 seconds as if the disk is being read or written to momentarily (or possibly the head is attempting to ...
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Retrieve data USB harddisk with I/O problem
I am having trouble with a USB drive.
It is a 2.5", 2TB spinner, that connects over usb.
It is used between operating systems (windows 10 and ubuntu)
Since a couple of days it starting giving ...
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How to redirect only part of output produced by a commmand?
Let's suppose I run a python program named test.py and want to save all it's output in a file.
We can easily do that via python3 test.py > output.txt
However, If the program produces a lot of lines,...
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Is it slower to read files from another partition?
Lets say there is a set of binary files in partition A. I copy them to partition B. I run a program that runs in partition A. Would it be slower for the program to read the files in partition B than ...
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A process that almost exclusively reads and writes stalls when kworker wakes up according to iotop
I have a 30GB file on an SSD disk and a process that continuously in a loop reads and writes from/to random locations in the file.
According to IO top, the process consumes almost max read and write ...
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Keyboard periodically stops working in Ubuntu 20.04
As the title says, I am having issues with my keyboard, where it will stop working after a period of roughly 20-30 minutes (it is difficult to get an exact time). While it is working, it works ...
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Is there a way to track the volume of a disk traffic from/to a particular file
I'm running a VM (qemu) that has its virtual disk on my hard drive. It works pretty slow so I'm thinking of moving that virtual disk to SSD. The only thing I am concerned about is whether it would be ...
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fio reporting high value of read iops at iodepth 1
I am using fio-2.2.10 on Ubuntu 16.04.
In one of my setup I am observing high value of read iops at io-depth = 1. One run is reporting iops=11418, another run iops=33507 andiops=44329. This does not ...
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Getting conflicting Hardware I/O write speed
I am getting two very different data rate from the dd command as shown below.
1st
dd if=/dev/zero of=/tmp/output conv=fdatasync bs=384k count=1k; rm -f /tmp/output
1024+0 records in
1024+0 ...
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Ubuntu 18.04 and 20.04 crash and freezes when interacting with USB-C. 16.04 working fine
I have an Asus Zenbook flip S (UX-370UAR, Intel Core i7-8550U CPU). It has as I/O only two USB-C ports and headphones port. It worked fine with Ubuntu 16.04.
Last year I changed to 18.04 (same is ...
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What's a convenient language/framework to use to do file system operations programmatically in Ubuntu?
Say I want to replace a specific string in all the file-names recursively within the directory, I know how to write java code to do that, but I'm expecting there would be something that might be ...
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Temporarily Disable ZFS ARC for Benchmarking
Is it possible to temporarily disable the ZFS ARC cache?
I am trying to benchmark a ZFS SSD array using fio and want to avoid ZFS caches (via the ARC) from skewing the results. The alternative of ...
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How to get I/O priority to work on Ubuntu?
Ubuntu has ionice, but as far as I can tell, it does absolutely nothing.
I suspect this is because Ubuntu replaced cfq with deadline and deadline doesn't support priorities.
Is there any possible ...
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Ubuntu 18.04 kernel 5.0.0 full system hang
we have been running our java system for over 2 years without ever having a system hang. We have 2 physical servers running similar java software (2 JVMs on each server) to form a cluster. As far as I ...
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Why does my external hard drive read and write speed drop to 0
I recently got a new external hard drive and have noticed that the write speeds are very slow. When I used "Benchmark Partition" from the Disks utility, I got a very strange result:
Why are the hard ...
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How to get "Total" Disk read/writes per process in ubuntu from terminal command?
How to get "Total" Disk read/writes per-process in ubuntu using the command line?
or "How to get all parameter values of system monitor using a command line like using top command or so per second."
...
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Why do I seem to type faster on my Ubuntu Virtual Machine (in Terminal)?
I notice that when I type in terminal on my Ubuntu VM launched via VirtualBox, the keyboard input is very slick, smooth, and fast.
Is it because the latency of keypress to screen has a faster setting ...
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ntfsfix shows no error but frequent IO errors on drive
I have a NTFS disk mounted as a data drive to a Ubuntu system (19.10).
In the last couple days, the drive has become very slow and unreliable.
The journal (journalctl -r) shows this :
Nov 20 15:...
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New HDD in 19.10: Where is 7MiB/s constant write activity coming from?
I just added a brand new 4TB spinning disk to my system, created one ext4 partition on it, labeled it HDD4 and mounted it exactly like /mnt/HDD (which works perfectly). It is /dev/sdc1.
Here is the ...
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Just installed LVM Raid 1 on a new server with 2x 10Tb hard drives and the Disk I/O is killing everything else every second
I copied a bit of data on my LVM based RAID1 (not hardware RAID) with 2× 10Tb hard drives:
/dev/mapper/users-users 9.1T 1.9G 8.6T 1% /home
and now it's killing my I/O to the point where my ...
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Battery drain & processor always at max
So, I've installed Ubuntu on my new gaming laptop (Xiaomi Gaming Laptop 2, NVidia GTX 1060, I7 8750H, 16GB RAM) and I've realised a very fast battery drain and heating, even at idle. At the beginning ...
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How can I restore DVD drive operation following most recent Ubuntu r19.04 `apt upgrade`
Some time in the last day or two, following one of the recent apt update-s the DVD driver on my desktop has stopped working.
between: 2019-09-15 (UTC) or so
until: 2019-09-20 (UTC)
After several ...
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Is the default 512 byte physical sector size appropriate for SSD disks under Linux?
GSmartControl and any other command line tool (like fdisk, smartctl, cat /sys/block/sd*/queue/hw_sector_size, cat /sys/block/sd*/queue/physical_block_size) I had used report the same for both of my ...
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I/O warnings and external entities
when entering the input:
sudo /usr/bin/vmplayer &
I receive the following error in my terminal's verbose output:
I/O warning: failed to load external entity "/etc/VMware/hostd/proxy.xml"
So my ...
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Input/output errors when running some programs in Lubuntu started from a bootable flash drive
I downloaded Lubuntu 18.04 iso file into my flash drive and make the flash drive into a bootable device.
I inserted the flash drive into a laptop (C55t-A) and booted into Lubuntu without actually ...
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How do I tell if a command is running or waiting for user input?
On command line, I typed a command and hit enter. It doesn't output anything . How do I tell if it's running and not yet output, or it's asking for user input?
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Compressing folder without using additional space on the drive
I have an 18GB EC2 instance that has run out of space. I wanted to zip and transfer files off the server to a local drive. There is just about 1% free space remaining on it. This means that I cannot ...
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Does any open source I/O benchmarking tool support ramping up IOPS?
I know that I can use fio to benchmark my disks with any given static workload. However, does any open source high quality benchmarking tool support doing a test where I select following parameters as ...
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6
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print_req_error: I/0 error
Every couple of days I get these errors that lockup the server.
[501.882940] print_req_error: I/O error, dev fd0, sector 0
[504.338961] print_req_error: I/O error, dev fd0, sector 0
[504.738984] ...
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Does storage affect file caching in cp?
I read somewhere that cp uses file caching, but why does coping something the size of ~100MB result in a file cache of more than 100MB in ram? Does this also change if copying from HDD -> HDD,SSD -> ...
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802
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call to iopl(3) ends with "Operation not permitted", even when running as root
On older systems you could call a function int iopl(int level) with argument level=3 to get a permission to perform raw I/O operations. On Debian this still works, but on Ubuntu 18, it always returns -...
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