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Aleksey Leshchuk alekseyl

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View comments_controoler.rb
class CommentsController < ApplicationController
# I assumed the usual naming for models and foreign columns
def users_comments
# I don't like where( post_id: Post.all ) but if table comments
# contains deleted posts comments or even NULLs than we need to keep it this way
@user_comments = Comment.where( post_id: Post.all )
.where(author_id: Author.where( username: params[:username]) )
end
end
@alekseyl
alekseyl / me_redis_configure.rb
Last active May 18, 2018
MeRedis confiugure examples
View me_redis_configure.rb
Redis.include( MeRedis )
# zip key crumbs user, card, card_preview, zips integer crumbs to base62,
# for keys starting with card_preview prefix compress values with Zlib
# for keys starting with user or card compress values with ActiveRecordJSONCompressor
Redis.configure(
hash_max_ziplist_entries: 256,
zip_crumbs: %i[user card card_preview], # -> { user: :u, card: :c, card_preview: :c0 }
integers_to_base62: true,
compress_namespaces: {
:card_preview => MeRedis::ZipValues::ZlibCompressor,
@alekseyl
alekseyl / json_compressor.rb
Last active May 17, 2018
JSON compressor example for me-redis gem
View json_compressor.rb
module RSmazCompressor
def self.compress(value); RSmaz.compress(value) end
def self.decompress(value); RSmaz.decompress(value) end
end
module ZLibJSONCompressor
def self.compress(value); Zlib.deflate(value.to_json) end
def self.decompress(value); JSON.load( Zlib.inflate( value ) )end
end
@alekseyl
alekseyl / calc_performance
Last active May 18, 2018
compare redis performance for ruby hmethods VS methods
View calc_performance
def calc_me_redis_perfomance_hash_zipping( zip_max = 128, sample_size = 10000 )
Redis.include(MeRedis)
redis = Redis.new
Redis.configure do |c|
c.zip_crumbs = :user
c.integers_to_base62 = true
c.hash_max_ziplist_entries = zip_max
end
@alekseyl
alekseyl / comparision
Last active May 28, 2018
comparision of redis memory optimization, for https://medium.com/@leshchuk/zipem-all-61076c7da4c
View comparision
# Columns:
# redis - clear memory usage of 100K values in Mb,
# gz - gz compressed value, smaz = smaz compressed value,
# key zip = zipping key crumbs to cingle char,
# me_ - memory_efficient_ hash optimization
#integers, html pieces, plain english text pieces
+----------+--------+--------+--------+---------+--------+----------+------------+
| type | redis | gz | smaz | key zip | me_* | kz+me+gz | kz+me+smaz |
+----------+--------+--------+--------+---------+--------+----------+------------+
@alekseyl
alekseyl / redis_memory_test.rb
Last active May 14, 2018
redis_memory_test example for key length comparision
View redis_memory_test.rb
def redis_memory_test
results = {}
redis = Redis.new
redis.flushdb
results[:clear] = redis.info(:memory)['used_memory'].to_i
(2..128).each do |i|
redis.pipelined do
10000.times { redis.incr( SecureRandom.urlsafe_base64( i ) ) }
View gist:76c37965c347b9e253580bde33fcd79e
# def to_base62
# Base62.encode(to_s)
# end
2.4.1 :001 > redis = Redis.new
=> #<Redis client v4.0.1 for redis://127.0.0.1:6379/0>
2.4.1 :002 > redis.flushdb
2.4.1 :003 > redis.info(:memory)['used_memory_human']
=> "670.55K"
2.4.1 :004 > redis.pipelined { 100000.times{|i| redis.incr( "user:#{i}" ) }; }; :done
@alekseyl
alekseyl / gist:c683346db6645f5353dceae4cb54a68c
Last active Mar 13, 2018
Array sampling perfomance in postgres
View gist:c683346db6645f5353dceae4cb54a68c
+----------------+-----------------+-----------------+-----------------+---------------+---------------+-----------------+----------------+----------------+
| N/cards/M | order by random | random() < 0.xx | generate_series | M partials | ruby way | Unfold | ORM random(rw) | ORM random(mp) |
| 10 / 10 / 5 | 0.32ms / 4.27 | 0.26ms / 3.55 | 0.25ms / 3.44 | 0.31ms / 4.13 | 0.28ms / 3.82 | 0.07ms / 1.0 | 0.17ms / 2.3 | 0.19ms / 2.55 |
| 100 / 10 / 5 | 0.66ms / 9.69 | 0.47ms / 6.9 | 0.26ms / 3.85 | 0.29ms / 4.22 | 0.31ms / 4.59 | 0.07ms / 1.0 | 0.2ms / 3.01 | 0.19ms / 2.74 |
| 1000 / 10 / 5 | 4.39ms / 10.09 | 2.98ms / 6.86 | 0.51ms / 1.16 | 0.57ms / 1.32 | 0.66ms / 1.51 | 2.89ms / 6.63 | 0.55ms / 1.26 | 0.44ms / 1.0 |
| 10000 / 10 / 5 | 43.06ms / 22.11 | 26.48ms / 13.6 | 1.79ms / 0.92 | 2.17ms / 1.11 | 3.18ms / 1.63 | 22.89ms / 11.75 | 3.01ms / 1.55 | 1.95ms / 1.0 |
+----------------+-----------------+-----------------+-----------------+----------
View gist:8abc0d088f30602b44a02d1723fc26bb
+----------------+-----------------+-----------------+-----------------+--------------+
| Array size | order by random | random() < 0.xx | generate_series | M partials |
| 10 | 0.25ms / 1.35 | 0.23ms / 1.2 | 0.12ms / 0.64 | 0.19ms / 1.0 |
| 100 | 0.58ms / 2.85 | 0.41ms / 2.04 | 0.14ms / 0.69 | 0.2ms / 1.0 |
| 1000 | 3.88ms / 7.3 | 2.49ms / 4.7 | 0.47ms / 0.88 | 0.53ms / 1.0 |
| 10000 | 45.59ms / 15.57 | 29.09ms / 9.94 | 2.87ms / 0.98 | 2.93ms / 1.0 |
+----------------+-----------------+-----------------+-----------------+--------------+
@alekseyl
alekseyl / devise_anycable_substitution.rb
Created Dec 15, 2017
devise anycable substitution example
View devise_anycable_substitution.rb
env['rack.session'] = ActionDispatch::Cookies::EncryptedCookieJar.new(cookies)[:_application_session]
current_user = Warden::SessionSerializer.new(env).fetch(:user)