Questions tagged [latency]
Latency is the time period between a signal being sent and a signal being received
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How much network latency is "typical" for east - west coast USA?
At the moment we're trying to decide whether to move our datacenter from the west coast to the east coast.
However, I am seeing some disturbing latency numbers from my west coast location to the east ...
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How to troubleshoot latency between 2 linux hosts
The latency between 2 linux hosts is about .23ms. They are connected by one switch. Ping & Wireshark confirm the latency number.
But, i dont have any visibility into what is causing this latency. ...
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Why is the response on localhost so slow?
I am working on a tiny little PHP project for a friend of mine, and I have a WAMP environment setup for local development. I remember the days when the response from my local Apache 2.2 was immediate. ...
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How does geography affect network latency?
I have the option of hosting our database/web server at a managed hosting company on the East Coast (US) or one on the West Coast (US). Our company is based out of New York City, and both hosting ...
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difference between taskset and cpuset
I'm trying to reduce the latency of my linux network application. I've learned that there are two tools for "binding" a program to particular CPU core: taskset and cpuset.
Which one should I prefer? ...
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Why do tracert latencies not add up to ping latency?
One might expect the sum of the tracert latencies to equal 267ms:
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Latency in Internet connections from Europe to USA
I'm looking for a (cheap) Web hoster. Basically all the hosting providers that I can find, and match my requirements are located in the USA.
But my target audience is in (Western-)Europe, I know for ...
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Data obtained from ping: is it round trip or one way?
I have 2 servers, each in two separate locations.
I need to host an application on one, and the database server on the other.
From the app server, if I ping the database server, on average I get ...
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Speed up SFTP uploads on high latency network?
I'm trying to transfer a set of large files internationally using SFTP, but I am finding my international partner can't get upload speeds above ~50k despite very good connections on either side. We ...
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Do changes in SPF records take time to propagate?
I'm setting up SPF records for my domain, and am not getting the results that I expect. It's quite possible I'm making some sort of mistake, but first I'd like to ask: does it take time for the ...
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Low latency TCP settings on Ubuntu
There is a server for measurements running on Ubuntu in my lab. And there is C program, which receives data through TCP connection and should as soon as possible send a reply.
Configuration
CPUs: 2 ...
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sssd and ldap authentication cache
On our box running OpenSUSE 12.2 we have installed OpenLDAP and sssd daemon. We are using these two services for user authentication. Recently we created a script which creates new web-users for our ...
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Does routing distance affect performance significantly?
When I say routing distance, I mean on a global scale. For instance, if my target audience is in China, do I look for a host within China?
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finding the best network latency between two countries
I know there are many tools to test for bandwidth and latency, but they all rely on having at least one host from which you can run those tests.
I wonder whether there's an online source or some ...
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6
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Intermittent high ping/latency problem
I have been working with my ISP (which is a WISP, actually Fixed Broadband Wireless) trying to figure out why I intermittently get high latency. The latency is detectable in online games and other ...
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Route traffic to node with lowest latency in HAproxy
Is it possible to route requests via HAproxy to a server that has the lowest latency from the source IP? This seems like a much needed requirement but I can't seem to find anything.
My problem is ...
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How do I test my internet connection speed via a Microsoft Windows Terminal?
I currently have two production servers. One running Windows Server 2003 and the other Windows Server 2008. When I open the Reliability and Performance Monitor I see a Network section that only goes ...
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Apache has a long lag before responding
I have an Apache server on CentOS that occasionally takes 1-5 seconds to serve a file, including a text file that is 2 characters. I have a JMeter test that gets a few different types of files, and ...
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Terminal server performance over high latency links
Our datacenter and head office is currently in Brisbane, Australia, and we have a branch office in the UK. We have a private WAN with a 768k link to our UK office and the latency is at about 350ms.
...
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How to apply `fq_codel` to balance traffic in multiple VLAN connections?
I have an Ubuntu server connected to multiple VLAN networks over a single physical 1 Gbps network port. The network connections are configured via /etc/network/interfaces like this:
auto lo
iface lo ...
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1
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How can I easily (e.g. as easy as rsync or SCP) do a high speed (1gpbs) file transfer over an Internet-latency link?
A few times per year, I need to transfer massive files (20+GBs) over the Internet (latency 20-100ms), but with reasonably fast connections on the order of 1gbps between servers. Unfortunately, when I ...
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Bandwidth throttling software
I need to be able to simulate high bandwidth/high latency/high packet loss on my pc for the purpose of testing the software that I'm writing.
I've seen some software that you can install on a ...
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Should I enable "Intel NIC DMA Channels"?
I have HP DL360p Gen8 646902-xx1
I'm trying to optimize my config for low latency trading.
Should I enable "Intel NIC DMA Channels"? Will that help/affect my system?
From HP doc:
Added a new ROM ...
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syslog-ng: How to reduce high latency when forwarding logs to a syslog tcp consumer?
UPDATE 2: I've answered this via my new question at the link below. The root cause is behaviour by telegraf where by default it disconnects the TCP connection 5 seconds after the last received message....
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Why my 2nd ip from traceroute is not answering the ping anymore? [closed]
My Internet is really laggy today, I did a tracerout and I realize that I'm having no answer from an ip at the beginning of the traceroute. see:
Tracing route to 12.129.202.154 over a maximum of 30 ...