Questions tagged [io]
IO or I/O is a common shorthand for referring to Input and Output
223
questions
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2answers
42 views
rm -rf foo_dir takes a long time
I have a directory ./aggregated/ in which I have 7550 sub-dirs each containing 250 files. aggregated has 5.5GB in total.
I've tried deleting aggregated via rm -rf aggregated and it is taking hours. ...
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0answers
22 views
Poor and strange disk performance with VirtualBox (macOS host, Windows 10 guest)
I have VirtualBox 6.1.4 running on macOS Mojave. I'm working with a Windows 10 guest and it seems I have some performance problems with disks.
Testing with Aja System Test, on macOS I see numbers ...
1
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1answer
33 views
How is I/O encryption handled in modern systems? [closed]
First: I've struggled with the question on which stackexchange to post this question since it involves OS knowledge, hardware knowledge but probably also other CS fields. Suggestions for a better ...
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0answers
9 views
read-only sd card / hdparm missing sense data [duplicate]
I have a micro SD card that used to be on an android tablet as internal storage, by mistake it was ejected.
Android says the sd is not supported, formating it as external/internal storage does nothing....
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0answers
139 views
Problems accessing disk after IO tests
I am having problems when accessing my home folder, or generally anything that is on my HDD (I also have an SSD which seems to work fine) in my ubuntu (18.04.4) workstation.
:/$ df -h
Filesystem ...
0
votes
1answer
46 views
What's happening when I create a file in a “NTFS compressed” directory?
What's exactly happening? The files appear in the UI as compressed. Is it?
If so, is it written twice (like, uncompressed version of the new files is stored, as a buffer, and compressed then (so ...
0
votes
1answer
40 views
How to determine the duration for which a file was accessed/modified a program?
I would like to measure the speed of encryption performed by a utility on a Windows 10 box. Since there are no other ways in the utility itself to do this, I would like to know if I can determine how ...
0
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1answer
49 views
Process ntoskrnl.exe CPU usage jumps from 1% to over 40% precisely when using I/O
the problem occurs with the following system.
Device: Lenovo Ideapad 730S - Windows version: 10.0.18362 Build 18362
So ntoskrnl.exe is running just fine as long as all the USB-C ports are left free. ...
0
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1answer
24 views
how to install kernel module for blk_mq's io schedulers?
I have recently changed single queue to multi queue on my oracle server. This server is oracle linux 6.10 (4.1.12 kernel). I realize there is no any io scheduler for blk_mq alse show the /sys/block//...
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0answers
23 views
which io scheduler is recommended when use the blk_mq block layer with oracle database?
I have oracle Linux 6.10 with 4.1.12 kernel. I have recently moved from the legacy block to the blk_mq block. But all SCSI devices have show io scheduler is none. I have researched but I didn't find ...
2
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0answers
229 views
Cannot diagnose slow disk read speed, bottleneck, in Ubuntu
I have the same processes running on 2 (or more machines) for which we notice a massive slow down in disk i/o on some machines. The PCs have very similar hardware (I am happy to post dmidecode if ...
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0answers
22 views
linux kernel 4.9 disk i/o throughput dropping and staying low
Summary: After upgrading to Debian9, kernel 4.9.x, I/O performance to disk drops to around 200-500kb/s after a while and stays low, even on an idle system. The only cure is an "echo 2 > /proc/sys/vm/...
0
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1answer
134 views
Is it safe to use one server fd in multiple epoll event loops in different threads?
I have one server fd, and several threads with epoll event loop in each of them (different epoll_fd's). Is it safe, if I would add this fd to every event loop? Is it true, that only one of them would ...
0
votes
1answer
63 views
Pipe stdout of two programs to each other
I have two programs, one of them prints something first, they need to communicate with each other with their standard IO.
Is there a way in Bash to pipe stdout of two programs to each other? I know I ...
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0answers
34 views
Making MsMpEng.exe disk access be nice
MsMpEng.exe disk accesses are making my system unusable. Since this process is critical for system security, it is unreasonable to disable it. Moreover, as it is provided by the OS vendor, and ...
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0answers
701 views
Very high disk usage due to reading from CbsPersist…log
My personal laptop is Windows 7, Dell, 8 CPU Cores and 8GB of RAM.
It operates very slowly, especially when launching software, and I think especially when starting up (but not only).
Looking at ...
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1answer
2k views
Trying to write to /sys/class/gpio/export – write error: Invalid argument
I have an Intel aaeon upboard and I want to use its GPIO pins. To do that I'm trying the below code:
echo 17 > /sys/class/gpio/export
But when I run it, this is what I get:
-bash: echo: write ...
1
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1answer
44 views
Where do Docker containers and Kubernetes pods write to disk in absence of a volume?
General question about the internals of Docker and containers running in Kubernetes when using the Docker engine.
Docker containers are ephemeral, meaning that if a container is destroyed, any data ...
0
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0answers
483 views
Unable to mount DVD - unable to read superblock
I bought a Documentary DVD online, but when I inserted the DVD into a Windows machine, nothing happened. So, I tried with Ubuntu, and same thing happened.
When I checked dmesg after I inserted the ...
0
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1answer
106 views
Does 'Write cliff' phenomenon only happen to SSD disks?
First of all, I am new to disks, I just know the basics. I am trying to improve performance of a software with heavy I/O and I need to understand how my SAS disks work in terms of read and write speed....
0
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1answer
389 views
CPU Burst or I/O Burst
If a process that currently is being executed faces an I/O Burst, will the next available process gain the CPU burst or will the processor wait until the I/O Burst of the first process finishes to ...
0
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2answers
142 views
What's the use of providing number of partitions when partitioning a hard disk?
I'm trying to partition my hard disk to make it usable. I'm following the steps given in this link to partition my hard disk. I'm doing this by providing the number of partitions as 1 and choosing the ...
2
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0answers
120 views
IOException - Leiningen REPL crashing while typing
I'm coding in Clojure and have been using Lein's REPL thoroughly. But recently it's been crashing while I'm typing, especially while opening or closing maps or parenthesis, with the following error ...
0
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1answer
31 views
How to save output of python-swiftclient to file when dowloading a directory?
When I download files from a cloud with python-swiftclient sometimes I get errors like this one:
Error downloading object 'uploads/1/image.png': Object GET failed: https://orbit.brightbox.com/v1/...
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0answers
20 views
What prevents my RT thread from working?
I have some data acquisition application running under Linux 2.6.37 on DM8148 with TI Linux. I have two threads:
thread named IDE, scheduled as SCHED_RR, prio 114 (75), which collects data from HW ...
3
votes
1answer
276 views
The request could not be performed because of an I/O device error
A few weeks ago something bad happened to my OS (Windows 10). In my laptop I have SSD with OS and HDD for data (cd drive slot).
I usually hibernate my PC instead of shutting it down. I also have a ...
0
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1answer
494 views
iostat + how to solve latency on disks
we use iostat -x and check for the await column - per device it shows the total time spent waiting plus the actual handling of the request by the disk
iostat -yzx 5
Device: rrqm/s wrqm/s ...
0
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1answer
46 views
Can Operating Systems handle shift, ctrl and alt key signals separate from the keyboard?
The basic problem is this: I have a mini keyboard I'm using for a Raspberry Pi project, and since there is only one shift, ctrl and alt key apiece, that means combinations on the left side of the ...
0
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1answer
24 views
Disk write issue but no error detected
I'm using a 3TB western digital red disk on my desktop pc (windows 10) and smart info says it's been powered on for nearly 1000 days,
I never had any issue with it before but now I'm having some ...
0
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0answers
56 views
Why firefox behaves so weirdly/annoying?
Occasionally FF starts very heavy activities, performing huge amounts of I/O (On my HDD) and considerable CPU usage for a long time (More than 10 minutes is really normal for it) that there is no ...
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1answer
62 views
Which filesystems reuse unchanged data blocks on write?
Let's say I open and read an existing file of N blocks where N > 1.
Then I change data which resides within the boundaries of one - 1 - block.
On writing back the actual data, presumably one of ...
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2answers
773 views
What are the relations between IO ports and registers in a device controller? [closed]
Do the following two references give different claims on the relations between IO ports and registers in a device controller? What are their relations actually?
Does the following quote from https://...
-2
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2answers
63 views
Are interrupts used to signify that output is ready or input has completed? [closed]
Operating System Concepts says:
During I/O, the various device controllers raise interrupts when they
are ready for service. These interrupts signify
that output has completed, or
...
1
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0answers
18 views
Mouting error bash on ubutun on Windows
I was running md5sum on a usb hard-drive via bash on Windows, but I had to terminated the program because of some errors. I tried to remount the drive and gives no error , but I was unable to cd ( ...
1
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1answer
261 views
Poor concurrent IO performance, how to trade latency for throughput?
I have a fairly IO-heavy GPU-limited process that needs to read in random files from a folder in a local hard drive. When the process is running by itself, I get a consistent throughput of around 30 ...
0
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1answer
1k views
Does porttalk work in Windows 10?
Porttalk is a driver that enables applications to access hardware's I/Os directly, like it was possible in Windows 98. Porttalk consists basically of two files:
porttalk.sys: The actual driver
...
0
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1answer
178 views
Is it possible to calculate theoretical i/o throughput of CPU?
I have machine with i7-2600K and I'm turning it into storage server. It's using P67 chipset which uses 20 Gb/s DMI interface to CPU. There are also pcie x8/x8 slots on board wired directly to CPU. I ...
0
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1answer
201 views
mounted local network synology folder : Input/Output error when tryign to write inside files
/etc/fstab mounts local network synology folder in Ubuntu 14.04 LTS like this:
//<numeric synology ip>/<synology_folder_name> /home/<user>/<mount_folder> cifs credentials=/...
1
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1answer
171 views
PORT-MAPPED I/O (Parallel Port)
I was reading into linux device drivers and reading and writing from parallel ports. I read something to the effect of
ioperm(from, num, turn_on) , where:
from is the first port number to give ...
1
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1answer
3k views
VirtualBox performance better with host i/o cache off
I was just building a vagrant environment with the box debian/stretch64. This is a test bed for ruby chef, so first thing my provisioner does is this:
apt-get install -y curl
curl -L https://...
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0answers
2k views
How to repair a micro SD card with I/O errors?
I have an 32 GB micro SD card which was able to let me copy data, but not alter data. After a lot of research, I came to the conclusion that the 'card detects a potential fault within itself. The ...
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0answers
149 views
How can I monitor data speeds on a Thunderbolt 3 port?
I am using a Thunderbolt 3 hub with two 4k monitors, Time Capsule, USB, and speakers, connected to it from my my MacBook Pro. This is all done with a single Thunderbolt 3 cable. Is it possible to ...
0
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0answers
51 views
Find exactly what PHP files are responsible for each PHP process
I have a WordPress website hosted on a shared Red Hat 4.4.7-18 Linux box, and from time to time I get huge memory and I/O spikes exceeding my allowed memory limit, making my website unresponsive.
I ...
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1answer
2k views
How does Raid 0 improve read performance?
Let's suppose we have 2 hard disks and stripe unit size is 64 kb.
While doing random read with size 4KB how Raid 0 affects performance?
I mean if we are doing random reads wouldn't operating system ...
-1
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2answers
124 views
What is a computation period? [closed]
In my textbook Operating Systems: Internals and Design Principles (Seventh Edition) by William Stallings I am confused by what the first problem (#2.1) on page 104 means by "period". Here is the ...
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0answers
48 views
Partclone taking 50 hours to back up 1 TB
I’m using Partclone 0.2.66 downloaded from the UBCD. I have a 3 TB hard drive split into three separate partitions of 1 TB each. It seems that there was a bunch of SMART errors on that drive, so I ...
0
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2answers
3k views
Synology Hyper Backup to external USB drive: Exception occurred while backing up data (Disk I/O error)
I am attempting to backup my entire Synology1 DS415+ NAS volume to an external Western Digital My Book 8 TB USB drive, using Hyper Backup.
The backup worked fine for about 10 hours, but suddenly ...
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0answers
93 views
How to redirect file I/O operations of a process to memory or a different file?
Let's say I have a file named file.txt and a running process with PID 12345 which sometimes reads and sometimes writes to that file.
Is there any way I can fool the process with PID 12345 to read or ...
0
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0answers
60 views
After moving to Win 10, Task Manager + Perfmon showing 0 byte/s and total HDD I/O when they should show > 100MB/s. Where have the stats gone?
In Windows 8.1 for years, I've been able to see the cumulative and per-second bytes R/W from disk migration in Task Manager, Resource Monitor, and Perfmon indicators.
I'm trialling vanilla new ...
0
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1answer
185 views
How do use Ubuntu/Windows to capture video from input?
My Panasonic DMR EZ48 VHS/DVD player has an HDMI output.
I want to copy VHS to digital files on my laptop.
I have a USB to HDMI converter. How do I use my laptop to capture video from the VCR? I am ...
