I am using forge viewer 7 version to load the models, sometimes when it takes more time to load them, either due to slow network or due to large models, the viewer looks like getting Timeout and says 'Disconnected'. Is there a way to increase this timeout?
I tried to find the viewer timeouts in documentation but couldn't find.
Error I am getting is "Disconnected!"
Afraid the connection was timed out on a networking level (browser/server shutting the connection down) so there's very limited control over that for Viewer or Javascript.
However you can set up a proxy service (see an example here) in your backend to relay the requests to and from Forge endpoints - this way you'd have control over the timeout settings in your backend and have the opportunity to optimize network traffic (backend server locality, SD-WAN etc comes to mind) or even cache the request contents to boost performance.
And when you said sometimes I suppose the model can be loaded properly when the networking conditions are better - if that's the case you can also consider caching the requests in the browser - see here for details.
Related
I have a full deployment of couchbase (server, sync gateway and lite) and have an API, mobile app and web app all using it.
It works very well, but I was wondering if there are any advantages to using the Sync Gateway API over the Couchbase SDK? Specifically I would like to know if Sync Gateway would handle larger numbers of operations better than the SDK, perhaps an internal queue/cache system, but can't seem to find definitive documentation for this.
At the moment the API uses the C# Couchbase SDK and we use SyncGateway very little (only really for synchronising the mobile app).
First, some relevant background info :
Every document that needs to be synced over to Couchbase Lite(CBL) clients needs to be processed by the Sync Gateway (SGW). This is true whether a doc is written via the SGW API or whether it comes in via server write (N1QL or SDK). The latter case is referred to as "import processing” wherein the document that is written to the bucket (via N1QL) is read by SGW via DCP feed. The document is then processed by SGW and written back to the bucket with the relevant sync metadata.
Prerequisite :
In order for the SGW to import documents written directly via N1QL/SDK, you must enable “shared bucket access” and import processing as discussed here
Non-mobile documents :
If you have documents that are never going to be synced to the CBL clients, then choice is obvious. Use server SDKs or N1QL
Mobile documents (docs to sync to CBL clients) :
Assuming you are on SGW 2.x syncing with CBL 2.x clients
If you have documents written at server end that need to be synced to CBL clients, then consider the following
Server side write rate:
If you are looking at writes on server side coming in at sustained rates significantly exceeding 1.5K/sec (lets say 5K/sec), then you should go the SGW API route. While it's easy enough to do a bulk update via server N1QL query, remember that SGW still needs to keep up and do the import processing (what's discussed in the background).
Which means, if you are doing high volume updates through the SDK/N1QL, then you will have to rate limit it so the SGW can keep up (do batched updates via SDK)
That said, it is important to consider the fact that if SGW can't keep up with the write throughput on the DCP feed, it's going to result in latency, no matter how the writes are happening (SGW API or N1QL)
If your sustained write rate on server isn’t excepted to be significantly high, then go with N1QL.
Deletes Handling:
Does not matter. Under shared-bucket-access, deletes coming in via SDK or SGW API will result in a tombstone. Read more about it here
SGW specific config :
Naturally, if you are dealing with SGW specific config, creating SGW users, roles, then you will use the SGW API for that.
Conflict Handling :
In 2.x, it does not matter. Conflicts are handled on CBL side.
Challenge with SGW API
Probably the biggest challenge in a real-world scenario is that using the SG API path means either storing information about SG revision IDs in the external system, or perform every mutation as a read-then-write (since we don't have a way to PUT a document without providing a revision ID)
The short answer is that for backend operations, Couchbase SDK is your choice, and will perform much better. Sync Gateway is meant to be used by Mobile clients, with few exceptions (*).
Bulk/Batch operations
In my performance tests using Java Couchbase SDK and bulk operations from AsyncBucket (link), I have updated up to 8 thousand documents per second. In .Net there you can do Batch operations too (link).
Sync Gateway also supports bulk operations, yet it is much slower because it relies on REST API and it requires you to provide a _rev from the previous version of each document you want to update. This will usually result in the backend having to do a GET before doing a PUT. Also, keep in mind that Sync Gateway is not a storage unit. It just works as a proxy to Couchbase, managing mobile client access to segments of data based on the channels registered for each user, and writes all of it's meta-data documents into the Couchbase Server bucket, including channel indexing, user register, document revisions and views.
Querying
Views are indexed thus for querying of large data they may will respond very fast. Whenever a document is changed, the map function of all views has the opportunity to map it. But when a view is created through Sync Gateway REST API, some code is added to your map function to handle user channels/permissions, making it slower than plain code created directly in Couchbase Admin UI. Querying views with compound keys using startKey/endKey parameters is very powerful when you have hierarchical data, but this functionality and the use of reduce function are not available for mobile clients.
N1QL can also be very fast too, when your N1QL query is taking advantage of Couchbase indexes.
Notes
(*) One exception to the rule is when you want to delete a document and have this reflected on mobile phones. The DELETE operation, leaves an empty document with _deleted: true attribute, and can only be done through Sync Gateway. Next time the mobile device synchronizes and finds this hint, it will delete the document from local storage. You can also use set this attribute through a PUT operation, when you may also adding _exp: "2019-12-12T00:00:00.000Z" attribute to perform a programmed purge of the document in a future date, so that the server also gets clean. However, just purging a document through Sync Gateway is equivalent to delete it through Couchbase SDK and this won't reflect on mobile devices.
NOTE: Prior to Sync Gateway 1.5 and Couchbase 5.0, all backend operations had to be done directly in Sync Gateway so that Sync Gateway and mobile clients could detect those changes. This has changed since shared_bucket_access option was introduced. More info here.
Currently working on the performance of my RESTFul api implemented using node js and mysql. For load testing of my APIs I'm using jmeter. So When I call my one of url for testing load with configuration
Virtual Users : 100,
Total Duration : 60s,
Time delay : 0s,
Ramup-Period : 1s
Jmeter show status OK for around 300-400 results and after that It timeouts for rest of request. Then after this I'm not able to ssh login or ping my server from my system till restart my system. Why this is happening?. Is it problem of my APIs design or server load problems.
Most probably your server simply becomes overloaded, I would suggest monitoring its baseline health metrics using top, vmstat, sar etc during your test execution. Also consider increasing your ramp-up period setting so load would increase more gradually - this way you will be able to correlate system behavior with the increasing load and determine what is the maximum of concurrent requests your system is able to serve.
Alternatively (or in addition to top, vmstat and sar) you can use JMeter PerfMon Plugin which is capable of collecting a lot of metrics and sending them to JMeter so you will have system performance report along with the load test results. Check out How to Monitor Your Server Health & Performance During a JMeter Load Test guide for detailed installation and configuration instructions along with usage examples.
I have an application hosted in openshift. Now I want figure out how many request can handle in order to check the speed and availability.
So my first attempt will be generate a multiple HTTP GET requests to my Rest Service(made in python and hosted in openshift).
My fear is can get my IP workplace banned regarding this looks like an attack.
In the other hand I see there are tools like New Relic or DataDog to check metrics, but I don't know if I can simulate http requests and then check the response times.
Openshift Response
I finally wrote to Openshift support and they told me I can simulate http requests without worries.
I recall the default behavior being that each gear can handle 16 concurrent connections, then auto-scaling would kick in and you would get a new gear. Therefore I would think it makes sense to start by testing that a gear works well with 16 users at once. If not, then you can change the scaling policy to what works best for you application.
BlazeMeter is a tool that could probably help with creating the connections. They mention 100,000 concurrent users on that main page so I don't think you have to worry about getting banned for this sort of test.
I wrote a web application using python and Flask framework, and set it up on Apache with mod_wsgi.
Today I use JMeter to perform some load testing on this application.
For one web URL:
when I set only 1 thread to send request, the response time is 200ms
when I set 20 concurrent threads to send requests, the response time increases to more than 4000ms(4s). THIS IS UNACCEPTABLE!
I am trying to find the problem, so I recorded the time in before_request and teardown_request methods of flask. And it turns out the time taken to process the request is just over 10ms.
In this URL handler, the app just performs some SQL queries (about 10) in Mysql database, nothing special.
To test if the problem is with web server or framework configuration, I wrote another method Hello in the same flask application, which just returns a string. It performs perfectly under load, the response time is 13ms with 20-thread concurrency.
And when doing the load test, I execute 'top' on my server, there are about 10 apache threads, but the CPU is mostly idle.
I am at my wit's end now. Even if the request are performed serially, the performance should not drop so drastically... My guess is that there is some queuing somewhere that I am unaware of, and there must be overhead besides handling the request.
If you have experience in tuning performance of web applications, please help!
EDIT
About apache configuration, I used MPM worker mode, the configuration:
<IfModule mpm_worker_module>
StartServers 4
MinSpareThreads 25
MaxSpareThreads 75
ThreadLimit 64
ThreadsPerChild 50
MaxClients 200
MaxRequestsPerChild 0
</IfModule>
As for mod_wsgi, I tried turning WSGIDaemonProcess on and off (by commenting the following line out), the performance looks the same.
# WSGIDaemonProcess tqt processes=3 threads=15 display-name=TQTSERVER
Congratulations! You found the performance problem - not your users!
Analysing performance problems on web applications is usually hard, because there are so many moving parts, and it's hard to see inside the application while it's running.
The behaviour you describe is usually associated with a bottleneck resource - this happens when there's a particular resource that can't keep up, so queues requests, which tends to lead to a "hockey stick" curve with response times - once you hit the point where this resource can't keep up, the response time goes up very quickly.
20 concurrent threads seems low for that to happen, unless you're doing a lot of very heavy lifting on the page.
First place to start is TOP - while CPU is low, what's memory, disk access etc. doing? Is your database running on the same machine? If not, what does TOP say on the database server?
Assuming it's not some silly hardware thing, the next most likely problem is the database access on that page. It may be that one query is returning literally the entire database when all you want is one record (this is a fairly common anti pattern with ORM solutions); that could lead to the behaviour you describe. I would use the Flask logging framework to record your database calls (start, end, number of records returned), and look for anomalies there.
If the database is performing well under load, it's either the framework or the application code. Again, use logging statements in the code to trace the execution time of individual blocks of code, and keep hunting...
It's not glamorous, and can be really tedious - but it's a lot better that you found this before going live!
Look at using New Relic to identify where the bottleneck is. See overview of it and discussion of identifying bottlenecks in my talk:
http://lanyrd.com/2012/pycon/spcdg/
Also edit your original question and add the mod_wsgi configuration you are using, plus whether you are using Apache prefork or worker MPM as you could be doing something non optimal there.
I'm having trouble with a web service deployed on Tomcat. During peak traffic times the server is becoming non response and forces me to restart the entire server in order to get it working again.
First of all, I'm pretty new to all this. I built the server myself using various guides and blogs. Everything has been working great, but due to the larger load of traffic, I'm now getting out of my league a little. So, I need clear instructions on what to do or to be pointed towards exactly what I need to read up on.
I'm currently monitoring the service using JavaMelody, so I can see the spikes occurring, but I am unaware how to get more detailed information than this as to possible causes/solutions.
The server itself is quad core with 16gb ram, so the issue doesn't lie there, more likely in the fact I need to properly configure Tomcat to be able to use this (or setup a cluster...?)
JavaMelody shows the service crashing when the cpu usage only gets to about 20%, and about 300 hits a minute. Is there any max connection limits of memory settings that I should be configuring?
I also only have a single instance of the service deployed. I understand I can simply rename the war file and Tomcat deploys a second instance. Will doing this help?
Each request also opens (and immediately closes) a connection to mySQL to retrieve data, I probably need to be sure it's not getting throttled there too.
Sorry this is so long winded and has multiple questions. I can give more information as needed, I am just not certain what needs to be given at this time!
The server has 16Gs of ram but how much memory do you have dedicated to tomcat, -Xms and -Xmx?