Questions tagged [latency]
Latency is the time difference between the start of an event and the time that the effects become noticeable.
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What does "Windows is not a real-time operating system" mean?
I came across an application called LatencyMon, that apparently does latency monitoring.
I have always understood that the more of a load you put on the processor, the less responsive, or more ...
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Latency of CPU instructions on x86 and x64 processors
I'm looking for some table or something similar that could help me to calculate efficiency of assembly code.
As I know bit shifting takes 1 CPU clock, but I really looking how much takes addition (...
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What do the memory timings and RAM mean?
On every piece of RAM you'll see the timings like: "2-2-2-5".
What is this all about? What should I buy?
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Does increasing upload or download speed reduce ping?
I have a 5 MB/s connection, but I always notice high ping when playing online games. When the network is stable (i.e. when pingtest.com reports the connection as 5 MB/s), the ping stays at 50 ms, but ...
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Negative ping time?
This is the first time I've seen this and I'm not sure what it means;
64 bytes from 74.125.93.99: icmp_seq=6233 ttl=53 time=545.493 ms
64 bytes from 74.125.93.99: icmp_seq=6234 ttl=53 time=776.093 ...
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Debugging Linux I/O latency
I'm having some I/O problems on a couple of Linux systems that I administer. They manifest in that processes often block for up to several seconds in such simple syscalls as open(), unlink() or close()...
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VLC Caching levels
When I open the Preferences of VLC and go to Input & Codecs, I have a setting called Default Caching Level. I can choose between
Cusom
Lowest latency
Low latency
Normal
High latency
Higher ...
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How does RAM frequency and latency differ? How does it affect performance?
I have a question regarding two specifications of RAM memory, the amount of Mhz and the latency timings (example: 9-9-9-24).
Which one of the two is most important for system performance and why? ...
user62234
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Network latency measurement (Linux)
I'd like to measure network latency for SNMP GET request.
There is a free command line tool time which can be used to find timing statistics for various commands. For example it can be used with ...
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Fixing bufferbloat in home network
In our home network, with continuous network IO happening latencies get ridiculous. It's fine with light loads but quickly becomes unusable if I'm, say, rsyncing a large number of small files, --other ...
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High DPC latency Windows 10, unable to fix
Edit: I am still experiencing this issue. ndis.sys is causing issues and I have not been able to resolve it. I am at a loss of what to do. I have tried reinstalling windows AGAIN, reinstalling drivers ...
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Xeon vs overclocked i7 Extreme for lowest latency
I am aware that the differences between high-end i7 and Xeon are:
compatibility with dual socket motherboards,
total L2/L3 cache size.
overclocking capability.
extra cores - Haswell i7-...
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Calculating hard disk block model reading time
My professor posted a slide on how to calculate the data retrieval from hard disk using the block model. The specs were:
7200 RPM
5ms SEEK
80MB/s TRANSFER RATE
BLOCK MODEL : Block size 4KB
I don'...
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Can I run games smoothly on a server via RDP? [closed]
Is it possible to run games on a hosted server smoothly via RDP?
I have a dedicated server running Windows Server 2012 R2. It has 144 GB of RAM, an Intel Xeon E5 and GeForce GTX 750 Ti GPU. It's a ...
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Very low latency streaming
I'm looking to stream a live lecture into an overflow lecture theater. I'm planning to stream HD content along with audio from a powerful server with nVidia GeForce GPUs connected to the client via a ...
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I sometimes get lag spikes causing ping times of 200 ms; might using different (e.g. Google's) DNS servers be better?
I live in the UK and I am a heavy gamer and I get lag spikes that take my ping to 200ms. Will using a third-party DNS Service, for example the one provided by Google, rather than those provided by my ...
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How to reduce latency with openssh?
I'm ssh-ing to a server several thousands kilometers away, and every keystroke takes 500-800ms, so it is getting annoying.
Is it possible to have my ssh client cache each line I type locally and ...
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Roommate lagging internet connection by watching videos from Chinese website. Can QoS fix issue?
My roommate is an international student from China and likes to watch Chinese TV shows online using a website based in that region (we're on the U.S. East Coast). But it causes our network's latency ...
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Alternating low and high ping times on ADSL line
I have an ADSL connection at home. Pings times are usually acceptable right after rebooting the modem, between 15 and 60ms to google.com. A few minutes later they go up to 900ms or even higher up to 3 ...
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Does RAM timings with n-n-n-3n value perform better than anything else?
I want to ask something:
Does RAM timings with n-n-n-3n (i.e. 8-8-8-24, 9-9-9-27, etc) perform better or is optimized more than the other who doesn't (i.e. 7-8-7-21, 9-9-9-24, etc)?
Frost Atronach
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Simulating network latency for localhost connection on Windows 7
I need to simulate network latency to a program running on the local computer, connecting to a local service. Thus far I have tried dummynet (a windows build of ipfw) which I got working after some ...
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(linux) tool to monitor "quality" of tcp connection?
I am looking for a tool to monitor the quality of a TCP connection. I am trying to describe what I mean:
It should be a tool with a client and a server part. The client sends, say, 1kB of data per ...
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How to reduce latency on FFmpeg video streaming?
On a video streaming application between Linux server (FFmpeg) and Windows client (VLC player), there is a noticeable latency of about 10 seconds.
FFmpeg command:
ffmpeg -re -f v4l2 -i /dev/video0 ...
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How Do USB 3.0 Hubs And USB Extension Cables Effect Latency, If At All?
I currently have three peripherals (mouse, keyboard, Wacom tablet) all wired to an individual USB port on my computer. They also each have their own 6ft USB extension cable (passive) because the ...
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Why do Jumbo Frames hurt latency?
Recently I've been reading about jumbo frames and I got confused in a few places. As far as I understand there is a lower bound on the Ethernet frame size between 'store and forward' points (layer 2 ...
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Low latency keyboards - are they for real?
Having just seen some commercial or other I just realized there could be such a thing as a high-latency keyboard—as compared to a low-latency keyboard. If so, then maybe a low-latency one could be yet ...
Tim Lovell-Smith
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Should the use of USB extension cables raise a concern about latency/performance?
Is there any need to be concerned about latency in transmission of any level of data/signal for USB devices when a USB extension cable is being used?
For this example lets say it's a 50cm cable (~1.6 ...
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SSH and Latent Connections (e.g., satellite connections)
Most of the week I live in the city where I have a typical broadband connection, but most weekends I'm out of town and only have access to a satellite connection. Trying to work over SSH on a ...
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High packet loss - all hops show red
I've run Ping Plotter and here are the results with high packet loss on all hops (around 12%). I find hard to believe Google's routers are faulty, is it my network card to blame?
Click the ...
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How to ssh in the face of huge (25 second) latency?
I need to create an ssh connection between two Linux machines running Centos v5 but the latency could be as high as 25 seconds. I find that if I test something approaching this configuration ...
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Latency of WiFi router
My current gaming desktop is connected to router via few meters of class 5 UTP. But I have to move it to another room, and I'm reluctant to drill holes in the wall to get cables trough. Currently I ...
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How to fight network latency and jitter issues on Wifi?
I'm having problems with my Wifi connection.
I did a test on PingTest.net with the following results:
Packet Loss: 0%
Ping: 103ms
Jitter: 29ms
Same test but from another machine on the network ...
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Increasing value of sched_latency_ns and sched_min_granularity_ns
Why do I get an error message when I try to increase the values of these two parameters:
#cat /proc/sys/kernel/sched_latency_ns
1000000000
#echo 2000000000 > /proc/sys/kernel/sched_latency_ns
bash:...
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Live Screencast under Linux
I was having some difficulty with running a Live Screencast under Linux. I've found jtvlc and tried using that, but whenever I use it the stream comes out either blank or lagged with extremely high ...
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How to solve extreme DPC latency peaks (240.000µs)
Once every few minutes I get a sudden peak of DPS latency that causes the system to "freeze" for a fraction of a second (240.000µs = 240ms).
The freeze is not only audio, also video, input devices, ...
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Does a USB-C ethernet adapter have a higher latency than a regular ethernet port?
Unfortunately, my new gaming laptop does not have a physical ethernet port. Will a USB-C to ethernet adapter produce the same latency(ping) as a physical ethernet port would? Also, how much CPU would ...
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TP-Link powerline adapter causing extreme latency on primary network? Wired devices on Fios router, not connected to powerline adapter, are affected
To preface, I am not a networking guy but work in IT. I'm going to bullet point the situation so it's easier to digest. Here is a little diagram I created in paint to give a visual aid.
I pay for ...
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Memory, more frequency, or more capacity?
My question my be simple, but I haven't been able to find an answer myself yet.
If you had the choice of getting either 24 GB of ram at 1333 MHz, or 12 GB @ 1600 MHz, which would you choose?
I know ...
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Which RAM should I prefer (CL vs PC)? [closed]
I'm thinking to buy new RAM (for Lenovo 320 15AST, motherboard is LNVNB161216).
I had 4GB, I need 8GB.
My current RAM is m471a5143sb1 2133Mhz, CAS (CL) 17, PC19200.
I was looking at two with such ...
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Many Transition from drive PhyRdy to PhyNRdy causing latencies in Windows 7?
My old Windows 7 pro sp1 laptop is becoming slow.
It freezes randomly for between 1 and 3 seconds before displaying a context menu, or when switching between windows.
After long searches, I suspect ...
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Nvidia Container causing audio popping and Explorer lag
I have been having this issue where my audio starts popping and crackling quite frequently (tried various audio devices, not specific to one device) and Windows Explorer generally becomes laggy and ...
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Very high latencies with WiFi
We bought a new WiFi router / ADSL modem at home (Asus DSL-N55U-B) and the wifi connection occasionally has very high latencies (up to 20 seconds, versus most common 25 miliseconds when pinging google ...
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Latency caused by ACPI.sys
(Specs below)
A few weeks ago, I started having problems with latency; all of a sudden audio and video weren't synchronised anymore and there were/was a lot of stutters and crackling (EDIT: my CPU ...
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How can I reduce latency on VLC
I 'm working on a video streaming application. Server is a Linux machine (ffmpeg-ffserver) and client is a Windows machine (vlc player).
There is a latency of about 6 seconds. Despite the fact that ...
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Windows 7 Lagging with multiple disks
I have an EVGA SR2 build with two Intel Xeon X5680, 48GB ram OCZ Reaper HPC Series at 1600 MHz running on Windows 7 x64 Proffesional. My bootable hard drive is an OCZ Vertex II 120GB and I have an ...
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How to increase transfer speed on fat long pipe?
I have a log pipe between two facilities (gigiabit circuit with RTT latency of 17ms). When doing system-to-system file transfer (file sharing, rsync, ftp, sftp) I'm hitting maximum speed of approx 30 ...
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Windows 7 Network Mystery
I'm having serious connectivity issues in Windows 7 and I'm out of diagnostic ideas. Here's way too much detail:
Machine is about 6 months old, haven't had a problem up until yesterday.
Internet ...
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Experiencing lockups due remote system Hard drive being shut off
Whenever I open a homegroup folder on another computer on my network, and the remote harddrive has to spin up, windows explorer seems to lock up until the remote request completes.
This affects ...
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What's the minimum network latency for a 1000 km connection using optic fibers?
I know most of the network latency for short distances is due to router processing times. But for longer distances the speed of light also counts. And it's different from the speed the light in the ...
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Sporadic high latency on my home network
tl;dr My home network recently has been experiencing jumps from 27ms latency to 600ms. It doesn't happen always, and seems to occur frequently at night. What equipment should I buy and tests should I ...
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