What is ping?

Modeling & profile generation

A look inside Vidora’s globally distributed, low-latency A.I.
This usually increases your latency and ping terribly. I had several ping issues in past and I tried everything I know. Secure OTR conversations on desktop, mobile. However, consumer- and server-grade Windows as of [update] those based on NT kernel were not to be real-time operating systems. Graphics Lag Hard — The granddaddy of all lag, this is the result of a general slowdown in graphics, and is a common occurrence for any gamer. There is a bit veracity dearth in both the article and comments.

Cricket API

Part 2: How to Compete with Broadcast Latency Using Current Adaptive Bitrate Technologies

From the point of view of flight operations personnel, latency can be entirely different. Consider the staff at the London and New York airports.

Only a limited number of planes are able to make the transatlantic journey, so when one lands they must prepare it for the return trip as quickly as possible. It might take, for example:. However, cleaning, refueling and loading the cargo can be done at the same time. Passengers can be loaded after cleaning is complete. The reduced latency, then, is:. The people involved in the turnaround are interested only in the time it takes for their individual tasks.

When all of the tasks are done at the same time, however, it is possible to reduce the latency to the length of the longest task. If some steps have prerequisites, it becomes more difficult to perform all steps in parallel. In the example above, the requirement to clean the plane before loading passengers results in a minimum latency longer than any single task.

Any mechanical process encounters limitations modeled by Newtonian physics. The behavior of disk drives provides an example of mechanical latency.

Here, it is the time needed for the data encoded on a platter to rotate from its current position to a position adjacent to the read-write head as well as the seek time required for the actuator arm for the read-write head to be positioned above the appropriate track. This is also known as rotational latency and seek time since the basic term latency is also applied to the time required by a computer's electronics and software to perform polling , interrupts , and direct memory access.

Computers run sets of instructions called a process. In operating systems , the execution of the process can be postponed if other processes are also executing. In addition, the operating system can schedule when to perform the action that the process is commanding. The operating system may choose to adjust the scheduling of each transition high-low or low-high based on an internal clock.

The latency is the delay between the process instruction commanding the transition and the hardware actually transitioning the voltage from high to low or low to high.

On Microsoft Windows , it appears [ original research? The sleep function or similar windows API were at no point designed for accurate timing purposes.

Certain multimedia-oriented API routines like timeGetTime and its siblings provide better timing consistency. However, consumer- and server-grade Windows as of [update] those based on NT kernel were not to be real-time operating systems.

Drastically more accurate timings could be achieved by using dedicated hardware extensions and control-loop cards. On embedded systems, the real-time execution of instructions is often supported by the low-level embedded operating system. Latency is sometimes also called transport delay. From Wikipedia, the free encyclopedia. This article needs additional citations for verification. We are not in such a hurry, so we can just type what we need and examine the result later.

The more feedback we receive during typing, the better. In principle, we can type with our eyes closed. We can continue typing even if we plug up our ears, relying only on tactile sensations from our fingers. However, if we block this last channel of feedback, typing becomes impossible. So far so good, but what is the reasonable bound? Remember your first attempts to use computer keyboard?

Most probably, it took you minutes to press a proper key and then verify the result on screen, this process demanded all your conscious attention. So, practice makes the difference. Such a process is called motor skill acquisition or motor learning. Formally speaking, typing is a process of motor control exercised by human motor system. Human response time is only relevant for error correction. But even semi-automatic processes are limited by vision delay pdf , and any feedback is only good if we can use it.

Human visual system needs about 40 ms to process its input. Again, this number depends on many factors, varies between individuals and can be improved by training. Yet, latency as small as 20 ms should be surely enough, right?

But then we can argue that something like 20 ms is comparatively small anyway. Well… human motor system have some clever tricks to react faster. To counteract input delays in sensory organs and nervous system, motor control relies on a special neural process, known as internal model.

This process can simulate response of controlled system before receiving feedback data — by relying on a forward model of the process. A supplementary inverse model is used to predict response of controlled system basing on actual feedback.

Forward- and inverse models are used in combination , with some internal feedback loops, producing nonlinear system. Thus, even small delays in feedback data might result in much bigger disturbances in typing. Apart from the internal model, there exists another process that is adversely affected by the visual latency, namely multisensory integration.

Visual image is not the only kind of feedback during keyboard typing: Each of these sensations is processed separately and nervous system is responsible for whether to integrate or segregate certain groups of signals. When brain receives stimuli from most sensory modalities immediately, but visual image is provided with some additional delay, it complicates things even further. Nervous system can to some extent adapt pdf to constant visual feedback delays though never perfectly , but any irregularities in delay durations so called jitter pose additional problem because of their inherent unpredictability.

There are a few illustrative examples from other areas where delayed feedback might be worse than no feedback at all, up to the point where primary activity becomes impossible: To get a feel of how latency, in general, manifests itself, I recommend you to check a great video from Microsoft Research that demonstrates that though in a slightly different context and shows that even 1 ms matters.

Needless to say, the possible impact of latency is hardly pleasant. The findings are generally agree with available research data. If you want to go deeper into the subject, you may check some books and scholarly articles that contain data on the effects of latency and the role of visual feedback in typing, for example:.

One thing especially worth quoting source:. Delay of visual feedback on a computer display have important effects on typist behavior and satisfaction. What happens between the moment you press a key and a character appears on the screen? It turns out, many, many things, and all of them take some time. Can we simply buy a top-of-the-line computer to ensure smooth typing? Take the both pills , and I will show you how deep the rabbit hole goes because even what follows is only a part of the whole truth.

Those kind of keyboards are most widely used nowadays both for desktop computers and in laptops. Typical keyboard contains more than keys, which is quite a lot. To minimize the number of wires and control processor inputs, key switches are usually connected in a matrix circuit , so that rows and columns of wires cross. The drawback of such an approach is that control processor cannot read state of all the keys simultaneously — it has to scan switches repeatedly, with some constant frequency, which results in some latency.

Typical matrix scan rate is Hz, so maximum scan-related latency is 1 ms average delay is 0. Regardless of keyboard type , key switches are mechanically imperfect and are subject to contact bounce — instead of a clean transition, the switch rapidly bounces between on and off states several times before settling.

Bounce time depends on switch technology, for example, for Cherry MX switches bounce time is claimed to be less that 5 ms. Though exact probability distribution is unknown, basing on related empirical data , we can assume that average bounce time is about 1. Because sampling rate is fast enough to misinterpret contact bounce as keystrokes, keyboard control processor perform so-called debouncing of the signals by aggregating them across time to produce reliable output. Such a filtering introduces additional delay, which varies depending on microcontroller firmware.

As USB is a host-driven bus, keyboard has to wait for a host request before sending the data about registered keystroke keyboard control processor places accumulated events in an output buffer. It also takes some time to actually perform data transmission. For high speed devices USB2 this time is much shorter — about 0.

The findings are generally agree with some experimental attempts to measure keyboard lag. All that can substantially reduce both maximum and average keyboard latencies. Processing latency is a delay between receiving the keyboard input and generating an image of the typed character in a video frame. Particularly, batching and buffering is often an attempt to attain higher performance at the expense of latency.

While conceptually there are many distinct sources of processing latency, in practice, they are so tightly coupled with editor application that all the parts are usually measured together see the next chapter for experimental data. Then the event is dispatched by event loop to active application window. All these actions require some time, yet this time is negligible for our purpose keyboard typing. Another OS-related source of possible processing delays are programs that add system-wide keyboard hooks and process the events synchronously.

For example, Workrave can noticeable increase the typing latency. NET Framework , additional delays might occur because those runtime environments are also not real-time systems with the exception of specialized implementations, like Real time Java. JavaScript engines and Emacs Lisp interpreter also exhibit those kind of delays.

Mainstream VMs have greatly matured over the years, nevertheless some prior warm-up might still be required to guarantee stable latency. This part is the most noticeable one, and rightly so. Editor application can give rise to the major part of typing latency. Unlike hardware-induced latencies, maximum delay time within editor is practically unlimited we might easily stumble on s lags. Because editor is mostly CPU bound , we can usually improve editor latency by using a more powerful machine good GPU also helps.

Also keep in mind, that even top-of-the-line laptop can be much more sluggish in power saving mode on battery , so this approach is effective only to a certain extent. Typing in editor is a relatively simple process, so even PCs were able to provide a rather fluid typing experience. See my article on low-latency painting in AWT and Swing for technical details despite the focus on Java platform, the key ideas can be extended to most modern operation systems and GUI frameworks. Next chapter contains a great wealth of empirical information on that topic.

CPU and GPU run in parallel and communicate through a command buffer , supplemented by an additional buffer in video driver.

Typical desktop applications works on top of GUI frameworks, so they are isolated from underlaying rendering pipeline and thus, from rendering synchronization. For example, see how synchronization in OpenGL works. You may also check the pipeline flush demo. Many GUI frameworks for example, Swing force double buffering by default.

Needless to say, this additional step leads to additional delay. Check the buffering overhead demo for more info. Today applications rarely run in full-screen mode, most desktop environments display each program in a separate window. This task is performed by so called window managers , which can be divided into several classes, depending on how windows are drawn and updated. Stacking window managers orchestrate drawing of overlapped windows in such a way, that background windows are painted first.

While this approach has some drawbacks window content has to be restored explicitly , it introduces no additional delays because applications draw directly in the framebuffer.

Examples of stacking window managers: Classic theme in Windows, Openbox in Linux. Compositing window managers substitute the framebuffer with a dedicated off-screen buffer for each window, and then display all the windows together when and how they see fit. This separation inevitable leads to some latency increase. Examples of compositing managers: Aero in Windows, Compiz in Linux. Vertical synchronization or V-Sync is a method of avoiding screen tearing — a condition when a display shows information from multiple frames in a single screen draw.

The resulting artifacts are mostly noticeable in horizontally-moving visuals with sharp vertical edges i. V-Sync boils down to waiting for a new frame in generated video signal before transferring back buffer to framebuffer so, V-Sync implies double buffering. Thus, we might expect additional delay before framebuffer update when vertical synchronization is turned on.

In Linux V-Sync seems to be disabled both with stacking- and compositing window managers. Today we have much better solutions see below. Those delays are much less predictable than hardware-induced delays and they are highly-sensitive to computer configuration. In principle, the total processing latency can be as low as ms, and as high as 10 s. Computer screen picture is stored in the frame buffer inside graphics card memory or inside shared graphics memory.

This transmission is performed at a fixed frequency, known as refresh rate , which is equal to 60 Hz for ordinary LCD monitors. While worst-case latency can be as high as frames up to 50 ms for 60 Hz refresh rate , display lag is mostly present in HDTVs, not computer monitors, so we can assume that this latency is close to zero for typical monitors.

LCD pixels cannot react to controlling voltage changes immediately. The amount of time a pixel in a display takes to change is called pixel response time. LCD monitors have come a long way in reducing pixel response time, so modern TN monitors most widely used nowadays exhibit average response times only about 4 ms. Typical setup consists of a usual, non-gaming keyboard and an ordinary LCD monitor. Ideal configuration presumes a low-latency keyboard and a low-latency gaming monitor. Both input and output components of the latency are precisely determined by periodical hardware processes that can be estimated with high accuracy.

Typical average latency of keyboard and monitor combined is about 26 ms, which is not much by itself, but when it adds up to processing delay it can make editor latency more noticeable. Theoretically, ideal processing latency can be close to ms. While every part of the chain matters, editor is the weakest link that can give rise to the major part of typing latency.

To measure processing delays experimentally I created Typometer — a tool to determine and analyze visual latency of text editors sources. Typometer works by generating OS input events and using screen capture to measure the delay between a keystroke and a corresponding screen update. Hence, the measurement encompasses all the constituents of processing latency i. That is the right thing to do, because all those components are inherently intertwined with the editor, and in principle, editor application has influence on all the parts.

Note that as I run benchmarks on the same hardware and all editor versions match, the results are directly comparable. Because results might vary depending on exact configuration, I used a rather typical setup for the benchmarking the machine is neither too slow, nor too powerful to make results more representative.

Only those editors that provide at least syntax highlighting were selected. Additionally, I excluded cases where editor runs in a terminal emulator , because terminal emulator itself can significantly influence the typing latency. The analysis was performed in R.

The charts were rendered via ggplot2. The Gang Beasts 0. We are still working on other stability fixes and minimising in-game exploits and other annoyances and expect to have more examples of this work in coming builds.

We have also started work on a full rebuild of the UI, localising for multiple languages, and a more standardised testing process with additional resources working with us to identify and fix issues.

We have pushed a server fix for the glue hand issue and patched 0. Please tell us if you still have issue with the 0. We are working on making a number of guides to give more instructive information on using and customising the Gang Beasts Server Tool and will be adding a specific sub-forum for the server tool the previous Server Tool forum was made inaccessible when the tool was associated with Gang Beasts on Steam.

To revert back to the last 'stable' branch select 'NONE- Opt out of all beta programs' from the same menu. For reference switching between 'unstable' and 'stable' branches of the game forces the selected build to download to the Steam client replacing the previously selected build.

A number of issues have impacted online multiplayer gameplay since the 0. A high number of player hosted servers registered or attempted to register with the master server in the days immediately following the release of the Gang Beasts server tool on 23 December , this negatively impacted on the performance of the Master Server. A significant percentage of player hosted servers that successfully registered with the master server player hosted servers that were shown in the server browser list did not have port forwarding configured or were otherwise inaccessible stopping other players from joining them.

To address these issues we have temporarily stopped player hosted servers from registering as public servers until the implementation can be modified remote players can still connect to player hosted servers with the Direct Connection option in the online menu. For discussion and support for the Gang Beasts Server Tool please use the forum at http: We have been testing to identify the source of the physics inconsistencies introduced in the 0.

We have been testing a potential fix for this issue and are publishing this as the 0. The modifications to the characters physics which are listed in the change log in the 0.

We are working on the Quick Join implementation to improve the management of contention for server slots with less frequent disconnections; if you have frequent issues connecting to servers with Quick Join please connect with the Server List with geographical filters to index servers in proximate geographies until improvements to the Quick Join implementation are published. A number of issues have impacted online multiplayer gameplay in the last days, the following paragraph summarises the issues with information on what work has been done to address the issues until full solutions are tested and published summarised in the next paragraph.

The volume of player hosted servers trying to register with the master server since the server tool was approved on 23 December has been impacting the performance of the Master Server. A significant percentage of these registered servers that were shown in the server list did not have port forwarding configured preventing them from being joined by other players. To address these issues we have temporarily stopped player hosted servers from registering as public servers players can still connect to player hosted servers with the Direct Connection option in the online menu.

Servers will be intermittently unavailable for the next hour as servers are modified the 0. Online multiplayer support in Gang Beasts has had numerous iterations since the online beta started in May and is now sufficiently stable and scalable to release in the default Early Access builds on Steam. For reference latency will be lower if you are can connect to servers close to your location you can use the server filter to show proximate servers , if there are no servers in close proximity to your location please email support boneloaf.

If you are playing from a location that is not close to the currently supported servers please test the dedicated server tool published with this post as a temporary solution until the server infrastructure is expanded to support your locality the server tool should be available through the Steam tools section and support Windows and Linux currently, please read the readme.

The list of modifications and fixes made to the online and server implementation in the 0. Local multiplayer support in Gang Beasts has seen a number of improvements and fixes including, an provisional support for in game camera modification single player only , support for playing online with multiple local players, provisional support for debug spawning we plan to expand debug spawning support to form the template for sandbox modes in later builds , and a basic version of the revised waves game mode currently limited to the grind stage.

We are still working to finish modified geometry for stages but are close to having final geometry on most stages excluding colour grading and post effects , the list of stages modified for the 0. Character movement, force parameters, concussion system, and targeting hierarchies have been modified to improve game play and the character customisation system has been exposed for testing, the full list of modifications to the character and character costume systems are:. To download the "unstable" branch on Steam right-click on the "Gang Beasts" game name on the Steam library page and select "Properties" from the window that opens, from this window select the "BETAS" tab and then the "unstable" option from the dropdown menu the menu labelled "Select the beta you would like to opt into: To revert back to the last 'stable' branch select "NONE- Opt out of all beta programs" from the same menu.

For reference switching between unstable and stable branches of the game forces the selected build to download to the Steam client replacing the previously selected build. Please post issues you identify with the 0. We plan to publish the 0. To force server compatibility we need to publish the 0. Currently we're working with Coatsink and SuperGenius to fix some stability issues with character costume parts and part combinations, other work has also been done to optimise the audio system, fix missing SFX, music and other audio, and fix issues with the character system.

We have also been working to standardise game menus and in game messaging. We have also been working with Coatsink to test Steam achievements and localisations, and to make the online multiplayer more stable and accessible including key work on server automation, polyinstancing, local and online lobbies, VoIP, and support for concurrent local and online multiplayer game sessions.

We will make a post with specific information on modifications and content in the 0. The character costume system has been populated with the costume parts examples are shown in the image made for the game to date, it is still missing some older costumes that need geometry modifying to make them compatible with the new costume system. Please note some costume parts have been made specifically for enemy AI gangs we plan to make these parts unlock-able in AI game modes.

Online gameplay in Gang Beasts is only supported in the "unstable" alpha builds on Steam Early Access, online support will be added to the default Steam builds when the 0. Online gameplay in Gang Beasts is currently supported in the "unstable" alpha builds on Steam Early Access online support will be added to the default Steam builds when the local multiplayer versions of the 'buoy' and 'fans' stages have been restored to the game.

Please note there is no "stable" alpha build release with this post, the next stable release will be published soon when the 'buoy' and 'fans' stages have been restored to the default local game mode. Online gameplay in Gang Beasts is currently supported in the "unstable" alpha builds on Steam Early Access support for online gameplay in the default Gang Beasts Early Access builds is scheduled for a later stage of development.

Please note there is no "stable" alpha build release with this post, the next stable release will be published when the 'buoy' and 'fans' stages have been restored to the default local game mode. Please note there is no "stable" alpha build release with this post the next stable release will be published when more optimisations and fixes have been made to the 0. For the last month we have been working with Coatsink to implement online support in the 0. The information in this post summarise a number of the key differences between the 0.

The structure of the 0. Downloading 'unstable' builds The instructions for updating from 0. The rest of this post is a series of paragraphs with current information and summaries on what progress has been made to date on content for the game.

“India's 10 Best Startups in AI”

Leave a Reply