pfreixes

GET /render?target=x
                ^
   |            |
   |            |
   |            |
+--|---------------------------+
|  |            |              | 
|  |         +--------------+  |
|  |         | consolidation|  |
|  |         +--------------+  |

pfreixes

Whisper data base format
------------------------

Byte Map of whisper file format

+------------------+
| Aggregation func | 4 bytes             - Type of allocate strategies for file
+------------------+                       * Use of fallocate if it is available, book the disk space
|    Max time      |                       * Use of sparse, fragmented, if it is configured.
|    retention     | 4 bytes               * Booking whole space writing zeros over there

pfreixes

Whisper example of update value
-------------------------------

Have a look to Whisper data format map to learn how it is https://gist.github.com/pfreixes/1b4c9f0cf1c2bd19edf9



Network packets : ts value
+------------------+
|  1401614544 10.0 | packet 1

pfreixes

"""Programs not ported to Python 3 that they are using specific 
operations with strings could raise undesirable bugs"""

>>> title = "Open binary file with python 3"
>>> fd = open("/tmp/wut.png", "rb")
>>> b = fd.read()
>>> type(b)
<class 'bytes'>
>>> b[0] == "\x89"
False

pfreixes

List of available events and their topics used by 
rabbitmq-event-exchange.

queue.*
consumer.*
user.*
permission.*
channel.*
policy.*
vhost.*

pfreixes

> db.test.find().count()
13
> db.test.find()
{ "_id" : "01-02" }
{ "_id" : "01-01" }
{ "_id" : "01-03" }
{ "_id" : "02-01" }
{ "_id" : "02-02" }
{ "_id" : "02-03" }
{ "_id" : "03-01" }

pfreixes

Boolean are integers, integers are immutable and immutable objects are shared along the life cycle of your programm. Then it comes true

>>> False is False
True
>>> 123 is 123
True
>>> [1] is [1]
False

pfreixes

#!/usr/bin/env python

UPPER_ITERATIONS = 10000000
    
def fac(n):
    if n == 0:
        return 1 
    return n * fac(n - 1)

pfreixes

N = 100000

# First approximation, brute force
def is_prime(number):
    if number == 2:
        return True
    for x in range(2, number/2+1):
        if number % x == 0:
            return False
    return True

pfreixes

All consumers consuming over 1K queues, growing from 1 to 1K messages.

consumer_threaded_pika.py

import pika
import threading
import sys
import time