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
Making GitLab Faster
Search
Yorick Peterse
June 04, 2016
Programming
2
470
Making GitLab Faster
Talk given at RubyC 2016
Yorick Peterse
June 04, 2016
Tweet
Share
More Decks by Yorick Peterse
See All by Yorick Peterse
Garbage Collection Crash Course
yorickpeterse
1
380
Rubinius & The Eternal Yak
yorickpeterse
1
270
Oga
yorickpeterse
3
200
Parsing for Humans
yorickpeterse
2
100
Other Decks in Programming
See All in Programming
CSC305 Lecture 08
javiergs
PRO
0
270
Vueのバリデーション、結局どれを選べばいい? ― 自作バリデーションの限界と、脱却までの道のり ― / Which Vue Validation Library Should We Really Use? The Limits of Self-Made Validation and How I Finally Moved On
neginasu
1
160
20251016_Rails News ~Rails 8.1の足音を聴く~
morimorihoge
2
670
XP, Testing and ninja testing ZOZ5
m_seki
3
790
Google Opalで使える37のライブラリ
mickey_kubo
3
130
NIKKEI Tech Talk#38
cipepser
0
120
CSC509 Lecture 05
javiergs
PRO
0
310
「ちょっと古いから」って避けてた技術書、今だからこそ読もう
mottyzzz
11
7k
Catch Up: Go Style Guide Update
andpad
0
240
Go言語はstack overflowの夢を見るか?
logica0419
0
520
その面倒な作業、「Dart」にやらせませんか? Flutter開発者のための業務効率化
yordgenome03
1
140
CSC305 Lecture 10
javiergs
PRO
0
220
Featured
See All Featured
Understanding Cognitive Biases in Performance Measurement
bluesmoon
31
2.7k
It's Worth the Effort
3n
187
28k
The Art of Delivering Value - GDevCon NA Keynote
reverentgeek
16
1.7k
Fashionably flexible responsive web design (full day workshop)
malarkey
407
66k
Put a Button on it: Removing Barriers to Going Fast.
kastner
60
4k
Navigating Team Friction
lara
190
15k
The Illustrated Children's Guide to Kubernetes
chrisshort
49
51k
Unsuck your backbone
ammeep
671
58k
Statistics for Hackers
jakevdp
799
220k
CSS Pre-Processors: Stylus, Less & Sass
bermonpainter
359
30k
Side Projects
sachag
455
43k
実際に使うSQLの書き方 徹底解説 / pgcon21j-tutorial
soudai
PRO
190
55k
Transcript
Making GitLab Faster
@yorickpeterse
[email protected]
GitLab Code, test, and deploy together
GitLab.com Statistics Users 544 306 Projects 955 340 Requests per
minute ~60 000 Storage ~30 TB
Response Timings Mean 350 ms 95th Percentile 1.23 s 99th
Percentile 3.17 s (backend only)
GitLab is slow, GitLab.com even more so
None
GitLab Problems
Limited production monitoring New Relic only on 1 out of
40 servers
No good development tools Only a collection of random Gems
No performance guides No guides on good/bad patterns, snippets to
use, workflow, etc
Lack of specialists Nobody was specifically focusing on performance
Badly Performing Code N+1 queries, inefficient algorithms, loading lots of
data into memory, etc
Solutions According to HackerNews
“Gitlab is one project that absolutely needs to be rebuilt
using Java. Both from a performance and a deployment perspective” https://news.ycombinator.com/item?id=11049717
“gogs was designed from the start to be fast. Nothing
but a rewrite would make GitLab as fast as gogs for basic stuff on small self-hosted servers.” https://news.ycombinator.com/item?id=11431410
Problem Solved! Let’s Rewrite GitLab in Java/Go/Haskell
Production Monitoring
Production monitoring is the first step to solving performance problems
GitLab’s Requirements 1. FOSS 2. Easy to set up 3.
Easy to query, visualize and add metrics 4. Low overhead 5. Support for percentiles
N-th percentile: N% of values are up to a given
value
“The 90th percentile is 1.5 seconds” means 90% completes in
1.5 seconds
GitLab Performance Monitoring
InfluxDB Time series DB with SQL-like query syntax
Grafana Time series visualization
Custom Ruby Code Used for measuring data, built from scratch
Transaction Metrics Rails, Grape, and Sidekiq
Code Region Metrics For measuring custom regions of code
Background Sampler Object counts, memory usage, GC statistics
None
None
Development Tools
Sherlock Development-only performance analysis, re-using the GitLab UI
1. Request details (URL, timings, etc) 2. Query timings, backtraces,
and EXPLAIN ANALYZE output 3. Line profiling
None
None
None
Documentation
GitLab Performance Guide Documents patterns to use/avoid, workflow, etc
http://docs.gitlab.com/ce/development/performance.html or https://is.gd/gitlab_webscale
Application Code
The language is rarely the problem
The database is not a black box
Rampant abuse of “pluck”
users.where(id: projects.pluck(:user_id))
users.where(id: projects.select(:user_id))
Combining Query Results
user.projects + public_projects + internal_projects
user.projects UNION public_projects UNION internal_projects
UNION not properly supported in ActiveRecord/Arel :<
Lots of Git Operations
if repo.exists? ... end
if repo.master_branch? foo end
Git Tag Existence https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/3983
if all_tags.include?(ref_name) => if tag_exists?(ref_name)
Markdown References https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/3969
for text in texts for reference in text process(reference)
process(texts)
1. Grab all references in a single pass 2. Query
any rows using the references 3. Replace text using the queried data
Calling “url_helpers” https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/3486
include app.routes.url_helpers
include Gitlab::Routing.url_helpers
def self.url_helpers @url_helpers ||= Gitlab::Application. routes.url_helpers end
Recap
Language/framework is usually only a problem when the application is
already fully optimized.
Take advantage of your database’s features
There is no silver bullet to fixing performance problems, it
simply takes time, effort, and patience.
Keep an eye on GitLab 8.9 for many performance improvements
Questions?