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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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What is the fastest posible way to comunicate to a server on Amazon EC2?

I need to communicate via WebSockes and normal HTTP. I am trying to save some microseconds. I have already done: I got an instance at the same Amazon EC2 zone. The ping is 1 millisecond. I have translated the application from Perl to Julia. It is a…
Pedro Serra
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Is asymmetric latency common in practice?

This is a follow-on to a question posted on stack overflow about whether it is possible to determine the one-way latency of a point to point connection without using externally synchronized clocks - turns out it isn't. Now the question here is if…
BeeOnRope
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Latency jumps in first, middle and last mile of path

I work for SD-WAN company providing an all in one solution edge router(Like FORTINET but not FORTINET). We have one customer in particular that has such a hard time with our services i.e. gift card servers unreachable, credit card processor…
Ixanthylus
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One machine's network usage can increase latency for everyone sharing the same ethernet switch

I'm managing an office network of about 20 computers, which all share a common ethernet switch (unmanaged), which is then connected to the ISP's cable modem/router combo. Every now and then someone will run some scripts that spawn many threads that…
user2468842
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~1300ms latency touching file on nfs mount

I have an NFS mount where the server is on the same subnet as the client. When I time touch testempty from the client, I get: touch testempty 0.00s user 0.00s system 0% cpu 1.325 total The time follows an bizarre pattern - Most of the time it's…
Dessa Simpson
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How to control AWS Elastic Beanstalk auto scaling based on average response times if one endpoint is expected to take circa 60 seconds

We auto-scale our Elastic Beanstalk Java Application based on the average response times exceeding 3 seconds. When this happens we add 2 instances to our environment. Once we are back within 1.5 seconds average response time then we reduce by 1…
RobbiewOnline
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ICMP maximum delay between echo request and reply sustained by a router NAT

I was trying to slow down network on my server (arch linux vm) with netem sudo tc qdisc add dev eth0 root netem delay 1600ms With 1600ms delay client doesn't receive the echo reply packet though the packet is generated from the serverside. However…
user59088
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Should things like database performance be included in a healthcheck

I manage a webservice and it is very important for my company to detect and notify if any of the services is down, and also if any of the operations it does is taking too long to respond. Until now there was a separated web application (including…
namelivia
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Multi-host VM/Docker network communication is SLOW, any best practice?

VM-1 on host-1 <[cable]> network router <[cable]> host-2 with VM-2 If I understand correctly, in case of file transfer from application on VM-1 to same application on VM-2 the data will go through following journey: VM-1 application file read to…
iXCray
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Reduce latency between USA users from EU server

I'm in a pickle. I had thought my server was in Canada, but turns out it is in France. I don't have the time for a server migration right now (it's the end goal as 75% if the visitors are USA). Using the website speed test on pingdom, the first byte…
Dan Hastings
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HTTPS over high-latency network

I'm building a web application that will be used in some remote parts of the country, normally with pretty awful options for internet access, usually satellite-based. Satellite internet generally has high latency; combine that with extreme weather…
James
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Receiving delayed emails, could it be my domain or MX records if not what else?

I noticed that when receiving emails on my domain they come delayed compared to another domains i have tested. The emails are being forwarded from a google email to two different addresses most of the time the emails are delivered with no delay but…
kroe
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Windows file server got slow response and high latency even ping localhost by running about 7 days after rebooting

We have a file server of Windows Server 2012 R2 on DELL PowerEdge R720, and get a very weird issue in recent days about network/disk performance. The box have a RAID-1 disk group for OS (disk0) under DELL H730P controller, and a SAN storage for Data…
Steven Wang
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Experiencing lower inter-rack ethernet speed compare to that of intra-rack

I have a cluster with 32 machines. The first 25 machines are on the first rack and the rest 7 machines are on the second rack. Each rack has a 1Gbps Ethernet switch. The network communication between the different racks will certainly have a…
syko
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CPU & Memory Reservation in vSphere & Numa concept

by googling/studying vSphere documentation I have found the possibility to use "Reservation" concept in vSphere. What it is not clear to me is : CPU and Memory reservations are configured separately and work differently. With memory reservations,…
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