I have a Meteor app that is based on the Meteor simple todos tutorial. I noticed, that the second node-process (smaller one) on the server, started later when the app is started up, increases its memory usage steadily, even when there is no activity at all but at least one client is logged on to the server. I trace the RSS-Memory value with
pmap -x $PID_node | tail -1 | awk '{ print $4 }'
but it is also visible with 'top'. The RSS number is increasing steadily when doing nothing at all on the client side. I added the app here for reproducing the behavior.
When I remember correctly it is the original state as I finished the tutorial without doing any custom changes.
When the client is disconnected the memory still remains and is not reduced by any means.This goes on until the app is closed on the server when reaching the memory limit. I encounter similar behavior with the official todos-example. I start the apps with
meteor --port 61100
I found in other posts that this could be related to a public folder which I even do not have in the simple todos so there must be something different. I also updated to the latest version of meteor 1.3.4.1 which does not change the behavior.
Is this a normal meteor behavior or has to be considered a meteor bug? Or is there any bad style code in the examples?
Related
I want to use dynamic and central configuration strategy for my microservices (MS) (multiple instances of same type having same configuration) and I'm using Azure App Configuration (AAC). I want to minimize calls to AAC so when one MS is starting I would like to read configuration from AAC and keep that until changes made i.e I dont want for every call to Configuration["Env:service:some-param"] generate calls to AAC. The notification part I have solved via eventgrid and servicebus-events so all MSs reaches notification that changes have been made but I really cant find any good solution to force to reload Configuration from AAC on demand.
In Program.cs I hook up AAC via:
config.AddAzureAppConfiguration(options =>
options
.Connect(connection)
.ConfigureRefresh(refresh =>
{
refresh.Register(environment + ":" + service + ":<Some-param>",true)
.SetCacheExpiration(TimeSpan.FromDays(1));
_environmentRefresher = options.GetRefresher();
})
why I set SetCacheExpiration(TimeSpan.FromDays(1)) is because I dont want to make unnecessary calls to AAC and I thought that if I fetch the refresher and triggers it when event occurs configuration would be reloaded but thats seems not to be the case due to SetCacheExpiration seems to override everything so my question is ... Is given scenario not solvable in .net core or can I achieve this in some way?
Make sure to call IConfigurationRefresher.SetDirty if you want to force the cache expiration to occur using an event based refresh model. Otherwise you'll encounter the problem you mention where the cache hasn't been invalidated yet and the refresh call will be a no-op.
Would you know how to run a background task on Symfony 4, based on the setup of a form ? This would avoid that the user has to remain on the form until the task is finished.
The idea would be that when the form is validated, it starts an independant background task. Then the user can continue its navigation and come back once the task is finished to get the results.
Thanks for your help,
You need to use pattern Message Bus. Symfony has own implementation of this pattern since version 4.1 introducing Messenger Component.
You can see documentation here: https://symfony.com/doc/current/components/messenger.html
To get it work you need some external program that will implement AMQP protocol. Most popular in PHP world IMHO RabbitMQ.
A very simple solution for this could be the following procedure:
Form is valid.
A temporary file is created.
Cronjob gets executed every five minutes and starts a symfony command.
The command checks if the file exists and if it's empty.
If so, the command works of the background task. But before this, the command write it's process id in the file to prevent from beeing excuted a second time.
Remove the file when the command has finished.
As long as the file exists you can show a hint for the user that the task is running.
I installed Symfony3 framework-standard-edition. I'm trying to open the home page(app.php prod) and it is loaded 300-400ms.
This is my profiler information:
also I use php7.
Why it is so long?
You can try to optimize Zend OPCache.
Here are some recommended settings
opcache.revalidate_freq
Basically put, how often (in seconds) should the code cache expire and check if your code has changed. 0 means it checks your PHP code every single request (which adds lots of stat syscalls). Set it to 0 in your development environment. Production doesn't matter because of the next setting.
opcache.validate_timestamps
When this is enabled, PHP will check the file timestamp per your opcache.revalidate_freq value.
When it's disabled, opcache.revaliate_freq is ignored and PHP files are NEVER checked for updated code. So, if you modify your code, the changes won't actually run until you restart or reload PHP (you force a reload with kill -SIGUSR2).
Yes, this is a pain in the ass, but you should use it. Why? While you're updating or deploying code, new code files can get mixed with old ones— the results are unknown. It's unsafe as hell
opcache.max_accelerated_files
Controls how many PHP files, at most, can be held in memory at once. It's important that your project has LESS FILES than whatever you set this at. For a codebase at ~6000 files, I use the prime number 8000 for maxacceleratedfiles.
You can run find . -type f -print | grep php | wc -l to quickly calculate the number of files in your codebase.
opcache.memory_consumption
The default is 64MB. You can use the function opcachegetstatus() to tell how much memory opcache is consuming and if you need to increase the amount.
opcache.interned_strings_buffer
A pretty neat setting with like 0 documentation. PHP uses a technique called string interning to improve performance— so, for example, if you have the string "foobar" 1000 times in your code, internally PHP will store 1 immutable variable for this string and just use a pointer to it for the other 999 times you use it. Cool.
This setting takes it to the next level— instead of having a pool of these immutable string for each SINGLE php-fpm process, this setting shares it across ALL of your php-fpm processes. It saves memory and improves performance, especially in big applications.
The value is set in megabytes, so set it to "16" for 16MB. The default is low, 4MB.
opcache.fast_shutdown
Another interesting setting with no useful documentation. "Allows for faster shutdown".
Oh okay. Like that helps me. What this actually does is provide a faster mechanism for calling the destructors in your code at the end of a single request to speed up the response and recycle php workers so they're ready for the next incoming request faster.
Set it to 1 and turn it on.
opcache=1
opcache.memory_consumption=256
opcache.interned_strings_buffer=16
opcache.max_accelerated_files=8000
opcache.validate_timestamps=0
opcache.revalidate_freq=0
opcache.fast_shutdown=1
I hope it will help improve your performances
[EDIT]
You might also want to look at this answer:
Are Doctrine relations affecting application performance?
TheMrbikus, try some optimization with the following elements:
Use APC
Use Bootstrap files
Reference: http://symfony.com/doc/current/performance.html
Use the OPCache PHP7
Use Apache PHP-FPM.
E-mail sending process, and may slow down during the form rendering operations. Create a blank test Controller.
This is pretty cutting-edge as 0.7.2 was just released today, but I thought I'd ask in case somebody can shed some light.
I didn't report this to MDG because I can't reproduce this on my dev environment and thus I wouldn't have a recipe to give them.
I've set up oplog tailing in my production environment, which was deployed exactly as my dev environment was, except it's on a remote server.
The server runs Ubuntu + node 0.10.26 and I'm running the bundled version of the app with forever. Mongo reports its replSet is working in order.
The problem is that some collection updates made in server code don't make it to the client. This is the workflow the code is following:
Server publishes the collection using a very simple user_id: this.userId selector.
Client subscribes
Client calls a server method using Meteor.call()
Client starts observing a query on that collection using a specific _id: "something" selector. It will echo on "changed"
Server method calls .update() on the document matching that "something" _id, after doing some work.
If I run the app without oplog tailing (by not setting MONGO_OPLOG_URL), the above workflow works every time. However, if I run it with oplog tailing, the client doesn't echo any changes and if I query the collection directly from the JS console on the browser I don't see the updated version of the collection.
To add to the mystery, if I go into the mongo console and update the document manually, I see the the change on the client immediately. Or if I refresh the browser after the Meteor.call() and then query the collection manually from the js console the changes are there, as I'd expect.
As mentioned before, if I run the app on my dev environment with oplog tailing (verified using the facts package) it all works as expected and I can't reproduce the issue. The only difference here would be latency between client and server? (my dev environment is in my LAN).
Maybe if somebody is running into something similar we can isolate the issue and make it reproducible..
Having a question on how the build queue is configured in CC.net.
I believe we have an issue , when trying to “force” build a scheduled project, the server tries to run several builds at the same time and fails
Most of them except the one that started first.
We need to get to a state when regardless how many builds are scheduled or how many we “force” start in about the same time, all build requests are placed in to a build queue and
executed one after finishing another in the order they were placed, and no extra request are generated.
Build Failed email is sent but the build was actually successful.
In short,The erroneous email is likely due to an error in the build server’s build scheduler/queue, trying to run 2 builds instead of one when asked for a “forced” build, as a result the first one is successful and the second one fails.
How to correct/resolve this issue....?
Thanks
Nilesh
To specify your projects' queue you need to set the queue property like this :
<project name="MyFirstProject" queue="Q1" queuePriority="1">
The default value is a queue per project. If you manually set the same queue (for example Q1) for all you project then, you will have a unique queue.
As for the queuePriority, the project (not yet started) in the queue are ordonned by queuePriority, low queuePriority projects start first.
It's all described in the cc net documentation which is now offline due to a problem at sourceforge.