Node too slow if ran from terminal - node.js

I've noticed that for some reason when I try to run a node script in terminal it's much slower than same statement in PHP no matter what.
test.js:
console.log("test");
duration # ubuntu:
aherne#aherne-NUC8i7INH:~$ time node test.js
real 0m0,317s
user 0m0,303s
sys 0m0,016s
test.php:
echo "test\n";
duration # ubuntu:
aherne#aherne-NUC8i7INH:~$ time php test.php
real 0m0,096s
user 0m0,021s
sys 0m0,028s
Am I doing something wrong or node is that slow? DISCLAIMER: I'm a beginner in node (obviously)

What are you trying to benchmark here? The startup times of each executable?
Obviously node is far more complex and has a higher startup time.
It is a very bad test since this is not what happens when php or node processes a user request - as the process will already be running.

Reason was ancient node version (10.19.0). After upgrading to v16.14.0 everything worked instantly:
aherne#aherne-NUC8i7INH:~$ time node test.js
real 0m0,057s
user 0m0,045s
sys 0m0,013s

Related

Selenium::WebDriver::Error with Firefox & Chrome

Problems
1. Browser = Firefox (Non Geckodriver, Selenium v2.53.4)
(Works on one linux thin client but not on another...)
$ bundle exec rake parallel:spec
Selenium::WebDriver::Error::WebDriverError:
unable to bind to locking port 7054 within 120 seconds
2. Broswer = Firefox (Geckodriver v0.14.0, Selenium-webdriver v3.1.0)
$ bundle exec rake parallel:spec
Net::ReadTimeout:
Net::ReadTimeout
3. Browser = Chrome (Chromedriver v2.27, Selenium-webdriver v3.1.0)
$ bundle exec rake parallel:spec
Selenium::WebDriver::Error::NoSuchDriverError:
no such session
(Driver info: chromedriver=2.27.440175 ,platform=Linux 3.16.0-0.bpo.4-amd64 x86_64)
My Setup
Server with the following installed:
-Linux - Debian x86_64 Wheezy
-ruby 2.2.5p319 (2016-04-26 revision 54774)
-Firefox v46.0.3
-Chrome 56.0.2924.87 (64-bit)
-ChromeDriver 2.27.440175
-Xvfb (x11-xserver-utils v 7.7~3 through headless gem)
Gems
-Selenium v3.1.0 (was 2.53.4)
-parallel_tests v2.10.0
-capybara (2.7.1)
-rspec-activemodel-mocks (1.0.3)
-rspec-core (3.4.4)
-rspec-expectations (3.4.0)
-rspec-mocks (3.4.1)
-rspec-rails (3.4.2)
-rspec-support (3.4.1)
-headless (2.2.3) (Xvfb)
Multiple thin clients running their software off the mentioned server setup.
My computer is one of many...
Important: There is another computer that does NOT encounter the mentioned problem running the same software and same versions off the same server!
Things that are NOT the problem
It is not an incompatibility between my firefox browser version and Selenium.
Why not?
a) Firefox v46.0.3 and Selenium v2.53.4 is currently installed on our server and another client of this server successfully runs parallel_tests using the mentioned versions of Firefox & Selenium.
b) Which Firefox version is compatible with Selenium 2.53.0?
There are no zombie processes(still running firefox) causing firefox to lock port 7054.
This is specifically after each failure has occurred and prior to starting a new $ bundle exec rake parallel:spec run.
Why not?
refer to items 1 & 2 in 'Things I Have Tried'
Turned Out this was not the case, although it was not the cause of the problem
Databases were not always properly killed, See Update 5.
However the databases not being killed were an outcome of the problem.
They were not the cause of the problem, refer to solution section.
Side note
For those wishing to install the mentioned versions to get selenium / firefox working:
Installing a previous version doesn't fix most problems
Things I have tried
Removed any processes still running
$ killall ruby; killall rspec; killall firefox
Result: Failed...
Discovered that completing step 1 is not enough to kill all zombie processes.
After logging out into a different tty i discovered that there was still an rspec, ruby and firefox process running!
So I logged out of my user, logged into a new tty, killed all zombie processes using:
$ kill -9 process_id
I then rerun $ ps aux to ensure all processes are cleaned.
Result: Failed...
Gain insight into the problem.
Ran $ lsof -i TCP:7054 see what is holding that process.
Result: It was my firefox test, no suprise, no real insight gained.
Ensured parallel test databases were running correctly.
Dropped all databases, recreated databases, reloaded all schemas, reseeded (development), reprepared.
Result: Failed... I doubted this was the cause, but doing this certainly eliminated it.
Deleted firefox cache, all persisted setting, everything, for a clean start.
Result: Failed...
Try to eliminate any local environment variables obtained from the project.
Did this by copying the project directory from the working computer.
Then reran $ bundle exec rake parallel:spec.
Result: Failed...
Try to eliminate all local environment variables (project and linux).
Did this by creating a new linux user.
Then switched into the new user.
$ su new_user -l
Copied over the minimum zsh items needed.
Then ran $ bundle exec rake parallel:spec
Result: Failed...
Ensured that /etc/hosts contained:.
127.0.0.1 localhost
Result: Failed...
Running the tests in a single thread (not parallel).
$ rspec spec
Result: Successfully runs (does not hit the problem)
See Update 1
See Update 2
See Update 3
See Update 4
See Update 5
Partial Solution
See Update 6
Debugged Selenium & Parallel_tests gems
Result: Identified that the issue is NOT in Selenium
See Update 7
Result: Running tests in parallel worked. But why?
See Update 8
Result:
Discovered Selenium 3.1.0 changed the way files are automatically downloaded.
This caused tests to hang indefinitely whilst running parallel test.
Which caused the databases to be held open.
Things I am going to try (Updates)
Run tests with chromedriver in chrome browser and see if it passes after the fix.
Update 1
I replaced firefox for chrome.
When I run a single test, the test successfully completes with chrome.
It did so with firefox as well.
However running $ bundle exec rake parallel:spec
Result: Failed...
Selenium::WebDriver::Error::NoSuchDriverError:
no such session
(Driver info: chromedriver=2.27.440175 ,platform=Linux 3.16.0-0.bpo.4-amd64 x86_64)
Update 2
I updated selenium-webdriver gem to the latest gem (was v2.53.4 now 3.2.2)
Result: Failed...
Selenium::WebDriver::Error::NoSuchDriverError:
no such session
(Driver info: chromedriver=2.27.440175 ,platform=Linux 3.16.0-0.bpo.4-amd64 x86_64)
Update 3
Located lock file for parallel test (~.config/google-chrome).
Identified 3 persisting lock files.
Other users only had 1.
Deleted these and reran tests.
Result: Failed...
Selenium::WebDriver::Error::NoSuchDriverError:
no such session
(Driver info: chromedriver=2.27.440175 ,platform=Linux 3.16.0-0.bpo.4-amd64 x86_64)
Update 4
Upgraded selenium-webdriver to v3.1.0 (latest stable)
Upgraded parallel_tests to v2.13.0 (latest)
Installed Geckodriver v0.14.0 (latest)
Then ran $ bundle exec rake parallel:spec
Result: Failed...
Failure/Error: visit "#/login"
Net::ReadTimeout:
Net::ReadTimeout
Update 5
Whilst in the firefox (Geckodriver v0.14.0, Selenium-webdriver v3.1.0) branch.
I only realised when I had to drop all my parallel_test databases that some were still open.
#ltsp:~/ap$ bundle exec rake parallel:drop[32]
Couldn't drop ap_test_andre32 : #<ActiveRecord::StatementInvalid: PG::ObjectInUse: ERROR: database "ap_test_andre32" is being accessed by other users
DETAIL: There are 3 other sessions using the database.
: DROP DATABASE IF EXISTS "ap_test_andre32">
Couldn't drop ap_test_andre25 : #<ActiveRecord::StatementInvalid: PG::ObjectInUse: ERROR: database "ap_test_andre25" is being accessed by other users
DETAIL: There are 3 other sessions using the database.
: DROP DATABASE IF EXISTS "ap_test_andre25">
When rake parallel:spec does not complete (indefinetly hangs during ),
the process must be killed manually.
Doing so leaves databases locked to the parallel_tests that were using them at the time.
So they must be identified and cleaned up.
postgres 743 0.0 0.0 222364 33628 ? Ss 15:30 0:00 postgres: andre ap_test_andre32 [local] idle in transaction
andre 24581 0.0 0.0 7852 2028 pts/36 S+ 15:49 0:00 grep andre32
postgres 26822 0.0 0.0 220032 23400 ? Ss 15:35 0:00 postgres: andre ap_test_andre32 [local] ALTER TABLE waiting
postgres 29684 0.0 0.0 220032 24064 ? Ss 15:40 0:00 postgres: andre ap_test_andre32 [local] ALTER TABLE waiting
Update 5 Solution:
search for database processes & kill all of them
ps aux | grep test_andre
andre#ltsp:~/ap$ sudo kill -9 743 26822 29684
I was then able to drop my databases.
bundle exec rake parallel:drop[32]
Update 6
Whilst in the firefox (Geckodriver v0.14.0, Selenium-webdriver v3.1.0) branch.
Cloned parallel_tests & Selenium projects locally.
Replaced my gems with a path to the locally cloned projects.
Debugged starting with the error stack trace.
Results
Updated to selenium 3.1.0 and loaded geckodriver (marionette).
I discovered that my firefox profile was not setup correctly with Capybara.
This broke my local single thread tests.
Fixed this.
Discovered that geckodriver is not to be used for FF<48.
Also discovered that the capybara, selenium 3+ & FF48+ combo is not yet ready for use.
Some vital functions are not working. (Right clicking, window resizing...)
Refer here for full details
After investigating parallel_tests, was able to rule that out.
Continued to debug in the firefox test case.
Used the locking port error as my guide.
Ruled out Selenium as the cause of the error.
After debugging the stack trace, it was proving to be very likely that the error state was inherited.
This was just a strong hunch at the time.
It later proved to be correct...
So summary here was that firefox had processes that were being locked.
And they were not being locked by Selenium.
Update 7
Whilst in the firefox (Selenium-webdriver v2.53.4) branch.
Went back to the new linux user that was created.
In light of Update 5, I dropped cleaned up all running processes.
Dropped all databases.
$ bundle exec rake parallel:spec
Result: Parallel tests worked
But why?
The databases were not the cause of the issue.
There was something else.
Update 8
Whilst in the firefox (Geckodriver v0.14.0, Selenium-webdriver v3.1.0) branch.
Identified the reason why the tests were failing and idenfinitely hanging.
This caused the issues described in Update 5 & 6.
It was caused by a change in the way Selenium accepts firefox profile settings.
I identified that the integration tests that were failing were ones that launched a pdf download.
Previously, I had this automated so that the download modal would not appear.
Instead it would automatically download the file to a specified folder.
Updating to Selenium 3.1.0 broke this.
Tests hanged indefinitely.
Databases were held open.
The problems identified, in the updates were not the root cause.
The root cause was that firefox/chrome browser ports were not closed and held open.
After looking at htop, Polkitd was seen to be taking up 16.5gb of ram!
This was caused by a memory leak in Polkitd.
After checking the issues it was confirmed that Polkitd memory leak is a know issue.
The issue has been fixed but only in later distributions of linux debian and not for Wheezy.
After restarting Polkitd, and rerunning the tests in parallel they worked!
This explains why the first time I created a new linux user with a clean profile the parallel test issues were still occuring. - Memory leaks are unpredictable.
It also explains why another computer did not run into the issue.
And why the second time I created a new user the parallel tests worked!
Phew, that took a lot of effort!
Polkitd was uninstalled as it was not needed for any printers or other software that we run.
Overall, if anyone else has the locking issue, it would be helpful to follow some of the process detection that I have done as some of the issues are common to all OS.

How can I get source code of nodejs from running app

I have accidentally delete source code of nodejs application, but this application is running, so how can I get source code back from running app?
I hope source code has been cached in some directory.
I was able to recover the full file by attaching the debugger (as TGrif suggested).
To actually recover the code:
Use setBreakpoint('app.js', 10), where 10 is a line of the code you know will be ran over again in the running process
Say pause, then next until it's paused on the script you want to recover.
Finally, say list(5000), where 5000 is an arbitrarily long number of lines to list.
You will now have your full script printed out, albeit with line numbers at the front, but you can use a site like this to remove them.
Hope this helps anyone who encounters this unique issue in the future, as this took me a couple hours to figure out.
There is maybe a way to retrieve some of your source code with the Nodejs debugger.
Assuming Linux OS, you need to get the process id of your application:
$ ps -e | grep node
Next you entering your app in debug mode with something like that:
$ kill -s USR1 PID
where PID is the pid of your node app.
Then your start the debug console:
$ node debug -p PID
If you have an app console, you'll see:
Starting debugger agent.
Debugger listening on port 5858
In your debug console you should see a debug prompt and you can get available commands with:
debug> help
I am able to show some of the running app source with the list command:
debug> list(NUMBER_OF_LINE)
where NUMBER_OF_LINE is the number of source code line you want to display.
I'm not sure this is a one shot try for you or not because my source code was not deleted.
Hope you can get some results.

How to run a nodejs script every second

I need to run my nodejs script for every second ,Similar to PHP cron jobs. I have tried some nodejs cron libraries like https://github.com/ncb000gt/node-cron but the issue was first run should be manual i:e I have to run the file with cron script for first time manually.
But in php cron jobs, they run by the server so if the apache server running script will automatically start and even if the script return an error for a cycle then script will run again from the beginning from the next cycle
So is there any way to achieve this in nodejs ?
You have two options:
using Node as a daemon, with something like Supervisord to run your node-cron script. This alternative is wasteful on resources such as RAM because Node and Supervisord are running all the time.
using the system's crontab, you can run your script like calling Node on the command line, such as * * * * node /path/to/your/script.js. This alternative is highly efficient but lacks some control, like being able to log the output in case of an error, although you could just pipe the output to a file: node script.js > logfile

switch_console.c:1053 We've become an orphan, no more console for us

I installed the Freeswitch on Ubuntu Image in the Docker, referring to the documentation mentioned here.
When I did the following:
Start FreeSWITCH
First Time
cd /usr/local/freeswitch/bin
./freeswitch
I got to the following screen on my command prompt.
And as the last line says, [WARNING] switch_console.c:1053 We've become an orphan, no more console for us., something is wrong here I believe.
As per the documentation, I was expecting the prompt, like freeswitch#domain> .
Does anyone know what could be the problem? Upon researching this error I landed at the source file many times at different places, for example, one mentioned here
I had the same problem.
If we look in the source code of Freeswitch, we see
if (getppid() == 1) {
switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "We've become an orphan, no more console for us.\n");
break;
}
We see that we had pid == 1, this mean that parent process for freeswitch is init process but we launched it in bash
docker run -it freeswitch_container bash
Problem described here
To solve this you just need to run another bash in running bash, so it will have pid != 1.

Error on neo4j server start on arch linux

I have an arch linux setup and installed neo4j through the arch user repository (yaourt -S neo4j), and I'm able to run the web console fine (sudo neo4j console with seemingly normal output and full functionality), however when trying to start the server (sudo neo4j start), I encounter the following error message:
/usr/share/neo4j/bin/utils: line 345: [: -lt: unary operator expected
Using additional JVM arguments: -server -XX:+DisableExplicitGC -Dorg.neo4j.server.properties=/etc/neo4j/neo4j-server.properties -Djava.util.logging.config.file=/etc/neo4j/logging.properties -Dlog4j.configuration=file:/etc/neo4j/log4j.properties -XX:+UseConcMarkSweepGC -XX:+CMSClassUnloadingEnabled
Starting Neo4j Server...cat: /run/neo4j/neo4j-service.pid: No such file or directory
process []... waiting for server to be ready. Failed to start within 120 seconds.
Neo4j Server may have failed to start, please check the logs.
rm: cannot remove ‘/run/neo4j/neo4j-service.pid’: No such file or directory
There's no delay before the error message is printed, so it seems to be something other than the timeout. I'm quite new to neo4j (I worked through a fair bit of the user manual using the web console, but no development or server config experience), so I'm not really sure what else might be relevant. I tried looking through the utils script and the error appears to be where it attempts to su neo4j, but it also seems to proceed to attempt to start the server. I also tried changing the port it's starting on as in this question, but no change. The only log I can find just has this over and over (with appropriate timestamps):
Oct 15, 2014 1:33:49 AM com.sun.jersey.server.impl.application.WebApplicationImpl _initiate
INFO: Initiating Jersey application, version 'Jersey: 1.9 09/02/2011 11:17 AM'
Any help at all would be appreciated!
EDIT:
The line 345 that it's failing on is the end of this snippet:
if [ $UID == 0 ] ; then
OPEN_FILES=`su $NEO4J_USER -c "ulimit -n"`
else
OPEN_FILES=`ulimit -n`
fi
if [ $OPEN_FILES -lt 40000 ]; then
From doing some echo debugging, it seems that su $NEO4J_USER is failing, probably because $NEO4J_USER is set to neo4j, a user that does not exist on my system. I tried setting that to root in one of the config files, but evidently that's not working properly. Arch is a continual learning experience for me, but I've not had to add a new user before to get software working.
The interesting line here is:
/usr/share/neo4j/bin/utils: line 345: [: -lt: unary operator expected
I assume that is caused by a wrong default shell for the neo4j user. What default is currently set for the neo4j system user? Try to switch that to bash. The startup scripts should work nicely with bash.

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