alonisser

cost of data structures

notes on redis memory usage - the previous is based on this post

redis memory optimization page

Interesting post by instagram engineering on this subject

The profiling tool: rdb tools

alonisser

1. replace apt-get upgrade to install only security patches:

http://askubuntu.com/questions/194/how-can-i-install-just-security-updates-from-the-command-line

2. use unattended-upgrade
3. automate unattended-upgrade with cron 
https://help.ubuntu.com/community/AutomaticSecurityUpdates

4. get alerts about pending updates:

alonisser

check redis log /var/logs/redis/redis-server.log for write errors  

can be permissions on the redis dbump dir or memory conditions or not enough place on disk

check place on disks:

http://www.cyberciti.biz/faq/check-free-space/
```
$ df -h
```

alonisser

##Redis
change redis conf in remote server


```
vim /etc/redis/redis.conf
# change the original to this line
bind 0.0.0.0
```

alonisser

for [this stackoverflow question](http://stackoverflow.com/questions/25558612/pillow-django-image-processing-the-file-you-uploaded-was-either-not-an-image-or)
    Running setup.py install for Pillow
        
        building 'PIL._imaging' extension
        /usr/bin/gcc -pthread -fno-strict-aliasing -g -O2 -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -DHAVE_LIBJPEG -DHAVE_LIBZ -DHAVE_LIBTIFF -I/usr/include/freetype2 -I/home/alon/server/django-warren/venv/build/Pillow/libImaging -I/home/alon/server/django-warren/venv/include -I/usr/local/include -I/usr/include -I/home/alon/.pyenv/versions/2.7.6/include/python2.7 -I/usr/include/x86_64-linux-gnu -c _imaging.c -o build/temp.linux-x86_64-2.7/_imaging.o
        _imaging.c: In function ‘_filter’:
        _imaging.c:877:8: warning: ‘kernelsize’ may be used uninitialized in this function [-Wmaybe-uninitialized]
             if (kernelsize != xsize * ysize) {
                ^
        /usr/bin/gcc -pthread -fno-strict-aliasing -g -O2 -DNDEBUG -g -fwrapv -O3 

alonisser

• snippet scream

• measuring tips

alonisser

http://stackoverflow.com/questions/244243/how-to-reset-postgres-primary-key-sequence-when-it-falls-out-of-sync/13308052#13308052)

http://reinout.vanrees.org/weblog/2011/05/12/sqlite-postgres-django-cms-migrations.html

https://www.vlent.nl/weblog/2011/05/06/integrityerror-duplicate-key-value-violates-unique-constraint/

https://gist.github.com/alonisser/7e931c68665721f0141c

alonisser

"""
This utility addresses the InegrityError that occurs when you try to add a new record to 
(probably a recently ported) postgres database while using Django, here's more . . . 

duplicate key value violates unique constraint "<app>_<table>_pkey"
DETAIL:  Key (id)=(2) already exists.

The problem here is that the Postgres sequence generators are out of sync with your data. 
Here's a good overview: http://www.vlent.nl/weblog/2011/05/06/integrityerror-duplicate-key-value-violates-unique-constraint/

alonisser

• uwsgi admin

• basic configuration

• options

• decorators

• set stats server

alonisser

ppa to add

sudo add-apt-repository ppa:pdoes/ppa #git
sudo add-apt-repository ppa:nginx/stable #nginx
sudo add-apt-repository ppa:chris-lea/node.js #node.js
sudo add-apt-repository ppa:fish-shell/release-2 #fish

In sources.list