Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Redis Hacks
Search
David Cramer
May 03, 2014
Technology
3
230
Redis Hacks
Python Nordeste 2014 - Lightning Talk
David Cramer
May 03, 2014
Tweet
Share
More Decks by David Cramer
See All by David Cramer
Mastering Duct Tape (PyCon Balkan 2018)
zeeg
2
880
Open Source as a Business (PyCon SG 2014)
zeeg
0
360
Angular.js Workshop (PyCon SG 2014)
zeeg
0
240
Architecting a Culture of Quality
zeeg
2
320
Release Faster
zeeg
12
1.4k
Open Source as a Business (EuroPython 2013)
zeeg
18
17k
Building to Scale (PyCon TW 2013)
zeeg
18
1.3k
Building to Scale
zeeg
28
24k
Lessons in Testing - DjangoCon 2012
zeeg
8
1.4k
Other Decks in Technology
See All in Technology
Amazon Q Developer for GitHubとAmplify Hosting でサクッとデジタル名刺を作ってみた
kmiya84377
0
3.5k
Amplifyとゼロからはじめた AIコーディング 成果と展望
mkdev10
1
360
Amazon ECS & AWS Fargate 運用アーキテクチャ2025 / Amazon ECS and AWS Fargate Ops Architecture 2025
iselegant
13
4.3k
登壇ネタの見つけ方 / How to find talk topics
pinkumohikan
3
250
Navigation3でViewModelにデータを渡す方法
mikanichinose
0
200
【TiDB GAME DAY 2025】Shadowverse: Worlds Beyond にみる TiDB 活用術
cygames
0
840
生成AIでwebアプリケーションを作ってみた
tajimon
2
120
標準技術と独自システムで作る「つらくない」SaaS アカウント管理 / Effortless SaaS Account Management with Standard Technologies & Custom Systems
yuyatakeyama
2
1k
UIテスト自動化サポート- Testbed for XCUIAutomation practice
notoroid
0
110
AWS Summit Japan 2025 Community Stage - App workflow automation by AWS Step Functions
matsuihidetoshi
1
140
Snowflake Summit 2025 データエンジニアリング関連新機能紹介 / Snowflake Summit 2025 What's New about Data Engineering
tiltmax3
0
220
Definition of Done
kawaguti
PRO
6
460
Featured
See All Featured
Balancing Empowerment & Direction
lara
1
340
Typedesign – Prime Four
hannesfritz
42
2.7k
Building Flexible Design Systems
yeseniaperezcruz
328
39k
I Don’t Have Time: Getting Over the Fear to Launch Your Podcast
jcasabona
32
2.3k
The Web Performance Landscape in 2024 [PerfNow 2024]
tammyeverts
8
660
実際に使うSQLの書き方 徹底解説 / pgcon21j-tutorial
soudai
PRO
181
53k
Build your cross-platform service in a week with App Engine
jlugia
231
18k
YesSQL, Process and Tooling at Scale
rocio
173
14k
Embracing the Ebb and Flow
colly
86
4.7k
Easily Structure & Communicate Ideas using Wireframe
afnizarnur
194
16k
Visualizing Your Data: Incorporating Mongo into Loggly Infrastructure
mongodb
46
9.6k
RailsConf & Balkan Ruby 2019: The Past, Present, and Future of Rails at GitHub
eileencodes
137
34k
Transcript
David Cramer twitter.com/zeeg Redis Hacks (or “How Sentry Scales”)
Buffering Writes
r = Redis() ! def incr(type, id): key = 'pending:{}'.format(type)
! r.zincrby(key, id, 1)
r = Redis() ! def flush(type): key = 'pending:{}'.format(type) result
= r.zrange(key, 0, -1, withscores=True) ! for id, count in result: prms = {'type': type, 'count': count, 'id': id} ! sql(""" update %(type)s set count = count + % (count)d where id = %(id)s """, prms)
Rate Limiting
r = Redis() ! def process_hit(project_id): epoch = time() /
60 key = ‘{}:{}’.format(project_id, epoch) ! pipe = r.pipeline() pipe.incr(key) pipe.expire(key, 60) result = pipe.execute() ! # return current value return int(result[0])
def request(project_id): result = process_hit(project_id) if result > 20: return
Response(status=429) return Response(status=200)
Time Series Data
def count_hits_today(project_id): start = time() end = now + DAY_SECONDS
! pipe = r.pipeline() for epoch in xrange(now, end, 10): key = ‘{}:{}’.format( project_id, epoch) pipe.get(key) results = pipe.execute() ! # remove non-zero results results = filter(bool, results) # coerce remainder to ints results = map(int, results) # return sum of buckets return sum(results)
Good-enough Locks
from contextlib import contextmanager ! r = Redis() ! @contextmanager
def lock(key, nowait=True): while not r.setnx(key, '1'): if nowait: raise Locked('try again soon!') sleep(0.01) ! # limit lock time to 10 seconds r.expire(key, 10) ! # do something crazy yield ! # explicitly unlock r.delete(key)
def do_something_crazy(): with lock('crazy'): print 'Hello World!'
Basic Sharding via Nydus
from nydus.db import create_cluster ! redis = create_cluster({ 'backend': 'nydus.db.backends.redis.Redis',
'hosts': { 0: {'db': 0}, 1: {'db': 1}, }, 'router': 'nydus.db.routers.keyvalue.PartitionRouter', })
def count_hits_today(project_id): start = time() end = now + DAY_SECONDS
! keys = [] for epoch in xrange(now, end, 10): key = '{}:{}'.format(project_id, epoch) keys.append(key) ! with redis.map() as conn: results = map(conn.get, keys) ! # remove non-zero results results = filter(bool, results) # coerce remainder to ints results = map(int, results) # return sum of buckets return sum(results)