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Keenan Brock kbrock

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kbrock / timing.rb
Created June 21, 2017 15:10
Metrics capture timing
def reload_models
[Vm, Host, Storage].each { |m| m.update_all(:last_perf_capture_on => 50.minutes.ago) } # <== still tweaking
[MiqTask, MiqQueue, Metric, MetricRollup, VimPerformanceState].each { |m| m.truncate}
ActiveRecord::Base.connection.execute("vacuum full")
Module.clear_all_cache_with_timeout
[[MiqProductFeature, :@feature_cache], [MiqProductFeature, :@obj_cache], [BottleneckEvent, :@event_definitions],
[Tenant, :@root_tenant]].each { |i, ivar| i.instance_variable_set(ivar, nil) }
MiqServer.my_server ; MiqServer.my_zone
[ExtManagementSystem, Host, EmsCluster, Tagging, Tag, HostStorage, Storage, Vm, MiqRegion, MiqTask, Relationship, Disk,
Endpoint, Authentication, ServerRole, MiqWorker, MiqQueue, MetricRollup, BottleneckEvent].each { |m| m.first }
@kbrock
kbrock / index.html
Last active July 31, 2017 18:12
references to MiqQueue, viewable https://rawgit.com/kbrock/8fdf74b6d518bd57b361fb5c511f8dc2/raw/index.html
<html>
<head><style>
table {border-collapse:collapse;}
table, td, th { border:1px solid black; }
.f0, a.f0 { color: #999; }
.f1, a.f1 { color: #ccc; }
</style>
</head>
<body>
<h2>!</h2>
@kbrock
kbrock / coordinator.rb
Last active June 8, 2017 02:08
multi threaded example
#!/usr/bin/env ruby
require 'thread'
COLLECTOR_COUNT = 2 # define to run in separate threads. comment to run inline
class Db
def initialize
@mutex = Mutex.new
@data = {}
end
def []=(n, v) ; @mutex.synchronize { @data[n] = v } ; end
@kbrock
kbrock / transaction_fix_repro.rb
Last active March 15, 2017 21:10
Reproduce rails transaction timeout error
#!/usr/bin/env ruby
begin
require "bundler/inline"
rescue LoadError => e
$stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
raise e
end
gemfile(true) do
@kbrock
kbrock / 00_stats.md
Created March 1, 2017 15:57
Aggregates comes together
ms bytes objects queries query (ms) rows comments
290.5 21,380,122* 225,801 2 28.0 1,598 before
244.9 18,410,393* 188,824 1 4.6 after

* Memory usage does not reflect 262 freed objects. (for both of them)

@kbrock
kbrock / benchmark.rb
Created April 21, 2016 00:51
Eval vs defined? for a class
require 'benchmark/ips'
def eval_eval_true
name = "Benchmark"
eval("defined?(#{name}) && #{name}.class").to_s.eql?('Module')
end
def eval_eval_false
name = "XABCDE"
eval("defined?(#{name}) && #{name}.class").to_s.eql?('Module')
@kbrock
kbrock / gist:70a401889571c8e80f540289b79457a5
Last active April 17, 2016 08:33
3 query plans
create index i_hosts_i_h on hosts(name, id);
create index i_hosts_h_i on hosts(id, name);
explain analyze verbose
SELECT "vms".id FROM "vms" left join "hosts" on "hosts"."id" = "vms"."host_id" ORDER BY "hosts"."name"
;
QUERY PLAN
-----------------------------------------------------------------------------------------------------------------------------
Sort (cost=440.76..448.26 rows=3000 width=36) (actual time=30.724..30.884 rows=3000 loops=1)
Output: vms.id, hosts.name
@kbrock
kbrock / comments.md
Created March 18, 2016 17:13
Comments on a seemingly "simple" PR

My comments on 7388

- s = MiqSearch.find(@sb[:planning][:options][:filter_value])
- s.options ||= {}
- s.options[:userid] = session[:userid]
- s.options[:results_format] = :objects
-vms, attrs = s.search
+ vms = MiqSearch.find(@sb[:planning][:options][:filter_value]).filtered(nil, :userid => current_user)
@kbrock
kbrock / just_sql.md
Last active March 15, 2016 13:58
Trying to mix and match active record AND OR 
create table tst(val int);
insert into tst values(1),(2),(3),(4),(5),(6),(7),(8),(9),(10);
select val from tst where (val=2) and (mod(val,2)=0) or (val >= 6);

| val |

@kbrock
kbrock / 01_desired.sql
Last active March 9, 2016 21:23
WITH RECURSIVE search_tree(id, path) AS (
SELECT id, ARRAY[id]
FROM services
WHERE id = 42
UNION ALL
SELECT services.id, path || services.id
FROM search_tree
JOIN services ON services.service_id = search_tree.id
WHERE NOT services.id = ANY(path)
)