drsnyder

# Create a user land file for testing.
# dd if=/dev/urandom of=/tmp/urandom bs=1M count=10
#
# urandom-reads.py infile threads
# Examples:
#   time python2.6 urandom-reads.py /tmp/urandom
#   time python2.6 urandom-reads.py /dev/urandom
#
# R to generate a plot of the read time distribution at each level of concurrency
# rdt = read.csv("output.csv", header=F)

drsnyder

boltzmann <- function(x, t=0.1) { exp(x/t) / sum(exp(x/t)) }
x=rnorm(10,mean=1,sd=0.5)
plot(boltzmann(x))
lines(boltzmann(x))

drsnyder

#!/bin/bash                                                                                                                                                                                                                                                                                                                                                               

#CREATE TABLE poky (                                                                                                                                                                                                                                                                                                                                                      
    #bucket varchar(256) NOT NULL,
    #key varchar(1024) NOT NULL,
    #data text,
    #created_at timestamptz NOT NULL DEFAULT NOW() CONSTRAINT created_at_utc_check CHECK (EXTRACT(TIMEZONE FROM created_at) = '0'),
    #modified_at timestamptz NOT NULL DEFAULT NOW() CONSTRAINT modified_at_utc_ch

drsnyder

__author__ = 'minesh'
from optparse import OptionParser
from qds_sdk.commands import *
from io import *

class ResultsFP:
    def __init__(self, filename):
        self.filename = filename

    def write(self, res):

drsnyder

{
  "_links": {
    "self": {
      "href": "/147/threads?viewableOnly=true&limit=25&page=0&sortKey=trending&sortDirection=descending&responseGroup=small"
    },
    "first": [
      {
        "href": "/147/threads?viewableOnly=true&limit=25&page=0&sortKey=trending&sortDirection=descending&responseGroup=small"
      }
    ],

drsnyder

for i in {1..20}; do ( time -p curl -I -s http://www.site.com )  2>&1  | grep real | cut -c6-; done | sort -n | awk '{ d[NR]=$1;  } END { print NR, "-", d[1], d[int(NR*0.5)], d[int(NR*0.95)], d[NR]; }'

drsnyder

test=# explain (analyze, buffers, verbose) update counters set count = count + 1 where count_type = 0 and count_id = 1;                                                                                     
                                                   QUERY PLAN                                                   
----------------------------------------------------------------------------------------------------------------
 Update on public.counters  (cost=0.00..5.03 rows=1 width=18) (actual time=0.036..0.036 rows=0 loops=1)
   Buffers: shared hit=6
   ->  Seq Scan on public.counters  (cost=0.00..5.03 rows=1 width=18) (actual time=0.020..0.021 rows=1 loops=1)
         Output: count_type, count_id, (count + 1), ctid
         Filter: ((counters.count_type = 0) AND (counters.count_id = 1))
         Rows Removed by Filter: 4
         Buffers: shared hit=5

drsnyder

test=# explain (analyze, buffers, verbose) update counters set count = count + 1 where count_type = 0 and count_id = 1;
                                                    QUERY PLAN                                                    ------------------------------------------------------------------------------------------------------------------
 Update on public.counters  (cost=0.00..5.74 rows=15 width=18) (actual time=0.110..0.110 rows=0 loops=1)
   Buffers: shared hit=20
   ->  Seq Scan on public.counters  (cost=0.00..5.74 rows=15 width=18) (actual time=0.014..0.054 rows=15 loops=1)
         Output: count_type, count_id, (count + 1), ctid
         Filter: ((counters.count_type = 0) AND (counters.count_id = 1))
         Rows Removed by Filter: 32
         Buffers: shared hit=5
 Total runtime: 0.137 ms

drsnyder

CREATE TABLE counters (                                                                                                                                                                                                                       
  count_type INTEGER NOT NULL,
  count_id   INTEGER NOT NULL,
  count      INTEGER NOT NULL
);

-- later to fix the issue
ALTER TABLE counters ADD PRIMARY KEY (count_type, count_id);

CREATE TABLE primary_relation (

drsnyder

import os                                                                                                                                                                                                                                     
import random
import time
import psycopg2

COUNTERS = 5 
THREADS = 10
ITERATIONS = 500 

def increment():