When we need memory related stats we add input plugin in telegraf.conf file.
[[inputs.mem]]
For application stats we keep input as statsd, we push stats from application using UDP to telegraf using its host and port.
[[inputs.statsd]]
Could someone explain how does [[inputs.mem]] input plugins get data related to memory? Because no one is pushing data to telegraf in this case.
Telegraf retrieves system data using system libraries written for Go. At this time it is using the gopsutil library. This library's link above includes an example of how it could be used within any Go program.
func main() {
v, _ := mem.VirtualMemory()
// almost every return value is a struct
fmt.Printf("Total: %v, Free:%v, UsedPercent:%f%%\n", v.Total, v.Free, v.UsedPercent)
// convert to JSON. String() is also implemented
fmt.Println(v)
}
This library supports a number of different operating systems and has modules for a variety of system information such as cpu, memory, disk, and networking usage. You can see where these are incorporated into the telegraf project here.
Related
I am working on an update procedure for the Cyclone10LP FPGA with Quartus Prime 20.1.1.
The platform design is done the following.
The NIOSII Software Build tool for Eclipse Project is configured according to the .sopcinfo file. The NIOSII soft core works properly.
However, executing the Altera provided HAL function altera_remote_update_trigger_reconfig(...) does not trigger the Remote System Update (RSU) for reconfiguration. A verification of the RSU was also done with discrete logic, there it works properly.
My code looks like the following.
int main()
{
altera_remote_update_state sp;
sp.base = REMOTE_UPDATE_0_BASE;
usleep(500000);
altera_remote_update_trigger_reconfig(&sp, 1, 0x800000, 0);
/* Event loop never exits. */
while (1);
return 0;
}
Any idea why the RSU does not work?
Verify, if the right address offset is used in the altera_remote_update_regs.h according to the Remote Update Intel FPGA IP User guide.
I had to adapt the address offsets of the registers. (Hint: the RU_BOOT_ADDRESS register from the User guide is the ALTERA_RU_PAGE_SELECT_REG in the altera_remote_update_regs.h.) It seems that the board support generation does not adapt all the needed parts.
Further details about the RSU on the basis of a Cyclone iV see: http://billauer.co.il/blog/2017/06/remote-update-intel-fpga-cyclone-iv/
We have a microservice that needs to be integration tested (real calls, but no network communication with anything outside of the test namespace in kubernetes) in our pipeline. It also relies on an external gRPC server which we have no control over.
Above is a picture of what we'd like to have happen. The white box on the left is code that provides the Microservice Boundary with 'external' data. It then keeps calling the Code via REST until it gets back the proper number of records or it times out. The Code pulls records from an internal database, as well as data associated to those records from a gRPC call. Since we do not own the gRPC service, but are doing integration tests, we need a few pre-defined responses to the two gRPC services we call (blue box).
Since our integration tests are self-contained right now, and we don't want to write an entirely new actual gRPC server implementation just to mimick calls, is there a way to stand up a real gRPC server and configure it to return responses? The request is pretty much like a mock setup, except with an actual server.
We need to be able to:
give the server multiple proto files to interpret and have it expose those as endpoints. Proto files must be able to have different package names
using files we can store in source control, configure the responses to each call
able to run in a linux docker container (no windows)
I did find gripmock which seemed almost exactly what we need, but it only serves one proto file per container. It supposedly can serve more than one, but I can't get it to work and their example that serves two files implies each proto file must have the same package name which will likely never happen with our scenarios. In the meantime we are using it, but if we have 10 gRPC call dependencies, we now have to run 10 gripmock servers.
Wikipedia contains a list of API mocking tools. Looking at that list today there is a commercial tool that supports gRPC called Traffic Parrot which allows you to create gRPC mocks based on your Proto files. You can give it multiple proto files, store the mocks in Git and run the tool in Docker.
There are also open-source tools like GripMock but it does not generate stubs based on Proto files, you have to create them manually. Also, the project up to today was not keeping up to date with Proto and gRPC developments i.e. the package name issue you have discovered yourself above (works only if the package names in different proto files are the same). There are a few other open-source tools like grpc-wiremock, grpc-mock or bloomrpc-mock but they still lack widespread adoption and hence might be risky to adopt for an important enterprise project.
Keep in mind, the mock generated will be only a test double, it will not replicate the full behaviour of the system the Proto file corresponds to. If you wanted to also replicate partially the semantics of the messages consider doing a recording of the gRPC messages to create the mocks, that way you can see the sample data as well.
Take a look at this JS library which hopefully does what you need:
https://github.com/alenon/grpc-mock-server
Usage example:
private static readonly PROTO_PATH: string = __dirname + "example.proto";
private static readonly PKG_NAME: string = "com.alenon.example";
private static readonly SERVICE_NAME: string = "ExampleService";
...
const implementations = {
ex1: (call: any, callback: any) => {
const response: any =
new this.proto.ExampleResponse.constructor({msg: "the response message"});
callback(null, response);
},
};
this.server.addService(PROTO_PATH, PKG_NAME, SERVICE_NAME, implementations);
this.server.start();
I am trying to connect my Adobe Captivate XApi course to the LRS (YetAnalytics). I have very less information as to what should i add in this code of tc-onfig.js in the course files:
// Pre-configured LRSes that should receive data, added to what is included
// in the URL and/or passed to the constructor function.
//
// An array of objects where each object may have the following properties:
//
// endpoint: (including trailing slash '/')
// auth:
// allowFail: (boolean, default true)
// version: (string, defaults to high version supported by TinCanJS)
//
TC_RECORD_STORES = [
{
endpoint : "",
auth : "",
allowFail: ,
version: "",
}
];
Generally you should avoid using that functionality. That code is leveraged by an underlying library in Captivate (Rustici Driver) for packages with a tincan.xml file. That package will be launched with an LRS endpoint and authentication credential which is where it will send the statements that it generates. Generally it is a much better idea to send all statements to that configured LRS and then figure out a way to get those statements either forwarded from or pulled from that LRS into your additional LRS(s).
This is for two main reasons. First by using this functionality you have to hard code a credential into the package which makes it insecure and indistinguishable during requests, this is generally just bad. Second, there is little to no error handling around calls that leverage this functionality, so if you set allowFail to false exceptions will go uncaptured and the content will likely behave in strange ways (or break completely), if you set allowFail to true then you will have no recourse when a call fails and you potentially will not know that you've lost data.
(Unfortunately, I know this because I implemented the functionality originally a very long time ago before fully understanding all of the ramifications.)
But just so I've answered your actual question, if you wish to not heed my advice, then the values that should go there will be passed through to the constructor for a TinCan.LRS object which is documented here: http://rusticisoftware.github.io/TinCanJS/doc/api/latest/classes/TinCan.LRS.html
The auth being the most tricky, it should be a value that is a full Authorization header value as needed to connect to the LRS, very often a Basic Auth header.
I'm currently writing some tests for an existing OpenResty application. It uses some shared dictionaries, which are created in the nginx.conf file via the lua_shared_dict directive.
I could write my own mock implementation for it, but I wonder if it is possible to programmatically create an ngx.shared.DICT object?
Is it possible to create it within Lua, or is it better to create a mock implementation yourself?
Background: My current test setup is quite easy. I use busted as a test framework and run it from the command line with the resty binary. The idea comes from this article.
I did not find a programmatic way to create the shared dictionaries, so I ended up mocking it:
ngx.shared.someDict = {}
ngx.shared.someDict.get = function(self, key)
return ngx.shared.someDict[key]
end
ngx.shared.someDict.set = function(self, key, val)
ngx.shared.someDict[key] = val
end
ngx.shared.DICT is ngx_shm_zone_t which used by nginx to share memory between process. accross to nginx guide , shared memory allocated when configuation parsed, So it may not possible to initialize in lua code. especially, ngx.shared.DICT is used to share memory between process. when worker has initilized, It's not possible to allocate memory shared with parent process by mmap call.
I'm working on an Adobe AIR application which can upload files to a web server, which is running Apache and PHP. Several files can be uploaded at the same time and the application also calls the web server for various API requests.
The problem I'm having is that if I start two file uploads, while they are in progress any other HTTP requests will time out, which is causing a problem for the application and from a user point of view.
Are Adobe AIR applications limited to 2 HTTP connections, or is something else probably the issue?
From searching about this issue I've not found much but one article did indicated that it wasn't limited to just two connections.
The file uploads are performed by calling the File classes upload method, and the API calls are done using the HTTPService class. The development web server I am using is a WAMP server, however when the application is released it will be talking to a LAMP server.
Thanks,
Grant
Here is the code I'm using to upload the file:
protected function btnAddFile_clickHandler(event:MouseEvent):void
{
// Create a new File object and display the browse file dialog
var uploadFile:File = new File();
uploadFile.browseForOpen("Select File to Upload");
uploadFile.addEventListener(Event.SELECT, uploadFile_SelectedHandler);
}
private function uploadFile_SelectedHandler(event:Event):void
{
// Get the File object which was used to select the file
var uploadFile:File = event.target as File;
uploadFile.addEventListener(ProgressEvent.PROGRESS, file_progressHandler);
uploadFile.addEventListener(IOErrorEvent.IO_ERROR, file_ioErrorHandler);
uploadFile.addEventListener(Event.COMPLETE, file_completeHandler);
// Create the request URL based on the download URL
var requestURL:URLRequest = new URLRequest(AppEnvironment.instance.serverHostname + "upload.php");
requestURL.method = URLRequestMethod.POST;
// Set the post parameters
var params:URLVariables = new URLVariables();
params.name = "filename.ext";
requestURL.data = params;
// Start uploading the file to the server
uploadFile.upload(requestURL, "file");
}
Here is the code for the API calls:
private function sendHTTPPost(apiFile:String, postParams:Object, resultCallback:Function, initialCallerResultCallback:Function):void
{
var httpService:mx.rpc.http.HTTPService = new mx.rpc.http.HTTPService();
httpService.url = AppEnvironment.instance.serverHostname + apiFile;
httpService.method = "POST";
httpService.requestTimeout = 10;
httpService.resultFormat = HTTPService.RESULT_FORMAT_TEXT;
httpService.addEventListener("result", resultCallback);
httpService.addEventListener("fault", httpFault);
var token:AsyncToken = httpService.send(postParams);
// Add the initial caller's result callback function to the token
token.initialCallerResultCallback = initialCallerResultCallback;
}
If you are on a windows system, Adobe AIR is using Microsofts WinINet library to access the web. This library by default limits the number of concurrent connections to a single server to 2:
WinInet limits the number of simultaneous connections that it makes to a single HTTP server. If you exceed this limit, the requests block until one of the current connections has completed. This is by design and is in agreement with the HTTP specification and industry standards.
... Connections to a single HTTP 1.1 server are limited to two simultaneous connections
There is an API to change the value of this limit but I don't know if it is accessible from AIR.
Since this limit also affects page loading speed for web sites, some sites are using multiple DNS names for artifacts such as images, javascripts and stylesheets to allow a browser to open more parallel connections.
So if you are controlling the server part, a workaround could be to create DNS aliases like www.example.com for uploads and api.example.com for API requests.
So as I was looking into this, I came across this info about using File.upload() in the documentation:
Starts the upload of the file to a remote server. Although Flash Player has no restriction on the size of files you can upload or download, the player officially supports uploads or downloads of up to 100 MB. You must call the FileReference.browse() or FileReferenceList.browse() method before you call this method.
Listeners receive events to indicate the progress, success, or failure of the upload. Although you can use the FileReferenceList object to let users select multiple files for upload, you must upload the files one by one; to do so, iterate through the FileReferenceList.fileList array of FileReference objects.
The FileReference.upload() and FileReference.download() functions are
nonblocking. These functions return after they are called, before the
file transmission is complete. In addition, if the FileReference
object goes out of scope, any upload or download that is not yet
completed on that object is canceled upon leaving the scope. Be sure
that your FileReference object remains in scope for as long as the
upload or download is expected to continue.
I wonder if something there could be giving you issues with uploading multiple files. I see that you are using browserForOpen() instead of browse(). It seems like the probably do the same thing... but maybe not.
I also saw this in the File class documentation
Note that because of new functionality added to the Flash Player, when publishing to Flash Player 10, you can have only one of the following operations active at one time: FileReference.browse(), FileReference.upload(), FileReference.download(), FileReference.load(), FileReference.save(). Otherwise, Flash Player throws a runtime error (code 2174). Use FileReference.cancel() to stop an operation in progress. This restriction applies only to Flash Player 10. Previous versions of Flash Player are unaffected by this restriction on simultaneous multiple operations.
When you say that you let users upload multiple files, do you mean subsequent calls to browse() and upload() or do you mean one call that includes multiple files? It seems that if you are trying to do multiple separate calls that that may be an issue.
Anyway, I don't know if this is much help. It definitely seems that what you are trying to do should be possible. I can only guess that what is going wrong is perhaps a problem with implementation. Good luck :)
Reference: http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/net/FileReference.html#upload()
http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/net/FileReference.html#browse()
Just because I was thinking about a very similar question because of an error in one of my actual apps, I decided to write down the answer I found.
I instantiated 11
HttpConnections
and was wondering why my Flex 4 Application stopped working and threw an HTTP-Error although it was working pretty good formerly with just 5 simultanious HttpConnections to the same server.
I tested this myself because I did not find anything regarding this in the Flex docs or on the internet.
I found that using more than 5 HTTPConnections was the reason for the Flex application to throw the runtime error.
I decided to instantiate the connections one after another as a temporally workaround: Load the next one after the other has received the data and so on.
Thats of course just temporally since one of the next steps will be to alter the responding server code in that way that it answers a request that contains the results of requests to more then one table in one respond. Of course the client application logic needs to be altered, too.