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Questions tagged [latency]

Latency is the time period between a signal being sent and a signal being received

Latency is the time period between a signal being sent and a signal being received. In computer networking this can be the time between a sending of a packet and receiving of a packet.

To illustrate we can use the ping command:

PING google.be (173.194.66.94) 56(84) bytes of data.
64 bytes from google.be (173.194.66.94): icmp_req=1 ttl=47 time=76.6 ms
64 bytes from google.be (173.194.66.94): icmp_req=2 ttl=47 time=74.8 ms
64 bytes from google.be (173.194.66.94): icmp_req=3 ttl=47 time=79.6 ms

The latency here is 76.6 ms.

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DNS Resolver Speed Techniques

I recently received a reply to my concerns about some DNS servers being slower than others despite all servers being anycast: In practice, most resolvers won't be impacted by the slower paths to some of the name servers in the set. Most …
Rob Olmos
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how can i reduce the lag in my sshd session?

I'm trying to use various ncurses programs through ssh but there's lag up/down in the sshd. I'm wondering if there are any tips like sshd config settings or tcp/ip settings that can help reduce the latency.
Joe Moe
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Is latency the time it takes to get the first byte?

If I request an image from a server, would latency be the time it takes to receive the first byte of the image?
Latency
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TCP handshake latency

I have 2 machines on a 100 Gb/s LAN which talk to each other over TCP. When I do a tracert or a ping from the client to the server, even a large ping, I get an answer in less then 1 ms. However, when I'm sniffing the TCP packets on the client side,…
Meidan Alon
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How remote warfare works when even my satellite TV and remote server has latency?

This question is after reading this article. My title asks it all. How the connection for this remote warfare works with a absolutely low network latency (which i believe is essential to achieve a remotely possible war experience) even after it…
blntechie
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Using SSH over high-latency connection (satellite)

Our only available ISP is satellite where we live. We're currently on HughesNet and waiting (very impatiently) for Starlink's beta to send us our invite. In the meantime, I still need to get into my Linode VPS from time to time, and it's not working…
CXL
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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 use rsync to do so it has all sorts of issues and…
john01dav
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Strongswan high latency on LTE

Allow me to ask for help to solve the following problem with latency. I have a network which is on one side the Strongswan server and on the opposite side are terminals connected through DSL, cable or wifi. When I am testing latency through the…
Petr W.
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Determining on which machine a packet/update arrived first

I have two separate AWS Virtual Machines set up within a region (different availability zones) both are connected via WebSocket (in Python) to a different load balancer (Cloudfront) of the same host server (also hosted with AWS) and receive frequent…
Huw Thomas
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VNET Peering Latency

I’m running a mission critical global three-tier-application (App, IIS & SQL Virtual machines) on same region (Central US), right now, some of the European users are suffering poor performance. I’ve decided to deploy IIS server at their regions…
Netanel Ben-Shushan
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Azure App Service / Postgresql high latency

We have an very simple Azure App Service application using Django (Python) running in West EU Region. The Service Plan for this Service is P1v2 (production plan). The Postgresql is configure with General purpose, 4cpu, 600 IOPS. The latency between…
Jerob
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NPing gives significantly less time on `TCP Connect` than `TCP`

I'm using NPing (NMap's pinging tool) to measure latency on specific servers that may not respond to ICMP. Also, servers do not usually run HTTP(S) and I only check latency on a specific TCP port related to the game counter-strike. I always try…
ruasoliveira
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What is a "normal" latency/performance of inserts on mariadb or mysql?

Hadn't used MySQL family for years. Now need to move from OracleDB to either MariaDB or PostgreSQL. So on a similar "hardware" (Openstack VM: RHEL 7.3, 4HT cores of 2.5GHz Xeon E312xx, "local" SAN & SATA storage) got Oracle11g and MariaDB10.3…
Vlad
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Is RTT theoretically the same regardless of ping origination?

Let's say you send a ping from device 1 to device 2. The result would give you the RTT. Theoretically speaking (because many variables are realistically in play), would the RTT be the same by pinging device 1 from device 2?
Sterling Butters
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Building reliable internet speed test tools

I'm interested in building a command-line speed test tool similar to the one used here. I started using it in a cron job to automatically check and record speeds at different times when we started having inconsistent download speeds at our office.…
user482740
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