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On Tue Oct 27, 2015, history.state.gov began buckling under load, intermittently issuing 500 errors. Nginx's error log was sprinkled with the following errors:

2015/10/27 21:48:36 [crit] 2475#0: accept4() failed (24: Too many open files)

2015/10/27 21:48:36 [alert] 2475#0: *7163915 socket() failed (24: Too many open files) while connecting to upstream...

An article at http://www.cyberciti.biz/faq/linux-unix-nginx-too-many-open-files/ provided directions that mostly worked. Below are the steps we followed. The steps that diverged from the article's directions are marked with an *.

1. * Instead of using su to run ulimit on the nginx account, use ps aux | grep nginx to locate nginx's process IDs. Then query each process's file handle limits using cat /proc/pid/limits (where pid is the process id retrieved from ps). (Note: sudo may be necessary on your system for the cat command here, depending on your system.)
2. Added fs.file-max = 70000 to /etc/sysctl.conf

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-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query 
FROM pg_stat_activity 
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' 
ORDER BY query_start desc;

-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query 
FROM pg_stat_activity 
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%' 

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Google Script CRUD

By Ryan Aunur Rassyid

Simply create RESTful API with Google Script and store it to Google SpreadSheet like a Pro.

Learn From http://www.androidlabs.info/appscript/crud-operation-on-google-spread-sheet-using-google-app-script-html-jquery/

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<?php

namespace App\Providers;

use App\Models\User;
use App\Observers\UserObserver;
use Illuminate\Support\ServiceProvider;

class AppServiceProvider extends ServiceProvider
{

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Simple automated GIT Deployment using GIT Hooks

Here are the simple steps needed to create a deployment from your local GIT repository to a server based on this in-depth tutorial.

How it works

You are developing in a working-copy on your local machine, lets say on the master branch. Most of the time, people would push code to a remote server like github.com or gitlab.com and pull or export it to a production server. Or you use a service like deepl.io to act upon a Web-Hook that's triggered that service.

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# Clean up Unused and Orphaned Persistent Disks

# Enable APIs and Clone Repository
gcloud services enable cloudscheduler.googleapis.com
git clone https://github.com/GoogleCloudPlatform/gcf-automated-resource-cleanup.git && cd gcf-automated-resource-cleanup/
export PROJECT_ID=$(gcloud config list --format 'value(core.project)' 2>/dev/null)
WORKDIR=$(pwd)

# Create Persistent Disks
cd $WORKDIR/unattached-pd

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iptables --insert INPUT --protocol tcp --dport 80 --jump ACCEPT
iptables --insert INPUT --protocol tcp --dport 8080 --jump ACCEPT
iptables --table nat --append PREROUTING --in-interface eth0 --protocol tcp --dport 80 --jump REDIRECT --to-port 8080
# run next line to have changes survive reboot
service iptables save

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Cloud Source Repositories: Qwik Start

# Create a new repository
gcloud source repos create REPO_DEMO

# Clone the new repository into your Cloud Shell session
gcloud source repos clone REPO_DEMO


# Push to the Cloud Source Repository

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IAM Custom Roles 

# Understanding IAM Custom Roles

<service>.<resource>.<verb>


# Viewing the available permissions for a resource
## List current permission
gcloud iam list-testable-permissions //cloudresourcemanager.googleapis.com/projects/$DEVSHELL_PROJECT_ID

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Understanding Your Google Cloud Costs

# Analyzing Billing Data with BigQuery
SELECT * FROM `billing_dataset.enterprise_billing` WHERE Cost > 0
SELECT Line_Item FROM `billing_dataset.enterprise_billing` GROUP BY Line_Item
SELECT Line_Item, COUNT(*) as NUM FROM `billing_dataset.enterprise_billing` GROUP BY Line_Item
SELECT Project_ID, COUNT(*) as num FROM `billing_dataset.enterprise_billing` GROUP BY Project_ID
SELECT SUM(cost) as Cost, Project_Name FROM `billing_dataset.enterprise_billing` GROUP BY Project_Name

# Visualizing Billing Data with Data Studio