Questions tagged [io]
I/O is an acronym for input/output, which refers to the mechanism or process for the transfer of information between one system or component and another.
646 questions
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What is the best way to detect busy CPU cores for blk-mq request steering in Linux kernel?
I am trying to implement request steering in Linux kernel’s blk-mq layer to distribute I/O requests across CPU cores based on load. My goal is to redirect requests from busy cores to less busy ones to ...
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USB Drive Read/Write Errors, Rasbperry Pi 3A+, Reproducable Error
Use Case
I am using a SanDisk Ultra USB 3.0 Drive (128GB Capacity) with a Raspberry Pi 3A+
The drive is mounted using /etc/fstab:
UUID=c85... /home/user/Videos/YouTube ext4 defaults,noatime,nofail 0 2
...
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when opening a FIFO for reading+writing, and blocking - how to tell if other side opened for reading or writing?
If I open a fifo for reading+writing in blocking mode:
fd = open("foo", "O_RDWR");
Then it blocks until someone on the other end opens it for either reading or writing. But how do ...
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disabling I8042 driver completely
"i8042 is still probing even though I disabled CONFIG_SERIO_I8042. Does it have dependent configurations? Even after passing kernel command-line arguments: i8042.nopnp i8042.noaux
, I still see ...
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2
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dm-crypt IOPS amplification
I have a ZFS pool comprising a mirror comprising two partitions encypted with dm-crypt.
$ zpool list -v data2
NAME SIZE ALLOC FREE CKPOINT EXPANDSZ FRAG CAP DEDUP ...
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Can DPDK Work With UEFI SecureBoot Enabled - Kernel Lockdown Mode?
Apologies in advance if I have incorrect assumptions in the post.
I'm still getting the hang of DPDK.
Basically, I am trying to utilize DPDK on a Generation 2 Hyper-V VM that has Secure Boot enabled.
...
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2
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Which is better when using a program that produces output to STDOUT the program's output option or output redirection
Is there any advantage/disadvantage to using a commands output option (usually -o) if you can just use output redirection (>).
Originally this question was specifically pertaining to cURL but after ...
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How exactly are results being passed among processes via the pipes?
So Unix follows a uniform approach to I/O that allows programs to connect via pipes. I also know that to do that it uses file descriptors. But I heard someone saying that pipes allow attaching the ...
- 171
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Slow write operation on NFS volume
I have a problem on NFS volumes that appeared two days ago. The problem seems related to write operations, with the following taking a longer time (10s of seconds) to complete :
sed -i
rm
Editing and ...
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Debian Bookworm - How to prevent block device seeking and probing when connected?
I have a small bootable system which requires access to storage devices, but not at the data level (i.e. just firmware commands), with the exception of a USB floppy drive whose data is accessed raw (...
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1
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Automatic flush of stream when reading input
I read in Advanced Programming in Unix Environment this:
Line buffering comes with two caveats. First, the size of the buffer
that the standard I/O library uses to collect each line is fixed, so
I/O ...
- 135
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4
answers
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Limit file IO speed
I am looking for a command similar to ionice and trickle and pv -L and tc - but which puts limits on IO to files.
ionice looks at block devices on the local machine. I want this to work for file I/O ...
- 37.5k
1
vote
1
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Understanding `pgpgin` in `/proc/vmstat` as I/O Counters: Relationship with I/O Bandwidth Measurements
Hi Kernel I/O Experts,
I have a question regarding the pgpgin and pgpgout counters in /proc/vmstat, specifically focusing on pgpgin. I’ve been exploring performance monitoring tools like vmstat and ...
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How to find the parent process of child processes causing heavy IO
I would like to find the parent process for a large amount of small child processes performing small IO operations.
For example, consider the following python script:
import os
import time
import ...
- 233
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How can I get the _real_ progress of dd, ignoring fast/staging buffers? [duplicate]
I'm using the dd command to write to a USB stick. My command is pretty straightforward:
dd if=myimage.iso of=/dev/sdd bs=1M status=progress
and indeed, I seem to be getting the progress reported:
...
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