9b1bdfefcd
Limiting only by client_name and query leads to a very poorly-indexed
lookup on `query` which throws out nearly all of its rows:
```
Nested Loop (cost=50885.64..60522.96 rows=821 width=8)
-> Index Scan using zerver_client_name_key on zerver_client (cost=0.28..2.49 rows=1 width=4)
Index Cond: ((name)::text = 'zephyr_mirror'::text)
-> Bitmap Heap Scan on zerver_useractivity (cost=50885.37..60429.95 rows=9052 width=12)
Recheck Cond: ((client_id = zerver_client.id) AND ((query)::text = ANY ('{get_events,/api/v1/events}'::text[])))
-> BitmapAnd (cost=50885.37..50885.37 rows=9052 width=0)
-> Bitmap Index Scan on zerver_useractivity_2bfe9d72 (cost=0.00..16631.82 rows=..large.. width=0)
Index Cond: (client_id = zerver_client.id)
-> Bitmap Index Scan on zerver_useractivity_1b1cc7f0 (cost=0.00..34103.95 rows=..large.. width=0)
Index Cond: ((query)::text = ANY ('{get_events,/api/v1/events}'::text[]))
```
A partial index on the client and query list is extremely effective
here in reducing PostgreSQL's workload; however, we cannot easily
write it as a migration, since it depends on the value of the ID of
the `zephyr_mirror` client.
Since this is only relevant for Zulip Cloud, we manually create the
index:
```sql
CREATE INDEX CONCURRENTLY zerver_useractivity_zehpyr_liveness
ON zerver_useractivity(last_visit)
WHERE client_id = 1005
AND query IN ('get_events', '/api/v1/events');
```
We rewrite the query to do the time limit, distinct, and count in SQL,
instead of Python, and make use of this index. This turns a 20-second
query into two 10ms queries.
|
||
|---|---|---|
| .github | ||
| .tx | ||
| .vscode | ||
| analytics | ||
| api_docs | ||
| confirmation | ||
| corporate | ||
| docs | ||
| help | ||
| locale | ||
| patches | ||
| pgroonga | ||
| puppet | ||
| requirements | ||
| scripts | ||
| static | ||
| stubs/taint | ||
| templates | ||
| tools | ||
| var/puppeteer | ||
| web | ||
| zerver | ||
| zilencer | ||
| zproject | ||
| .codecov.yml | ||
| .codespellignore | ||
| .editorconfig | ||
| .eslintignore | ||
| .eslintrc.json | ||
| .gitattributes | ||
| .gitignore | ||
| .gitlint | ||
| .mailmap | ||
| .npmignore | ||
| .npmrc | ||
| .prettierignore | ||
| .pyre_configuration | ||
| .readthedocs.yaml | ||
| .sonarcloud.properties | ||
| CODE_OF_CONDUCT.md | ||
| CONTRIBUTING.md | ||
| Dockerfile-postgresql | ||
| LICENSE | ||
| manage.py | ||
| NOTICE | ||
| package.json | ||
| pnpm-lock.yaml | ||
| prettier.config.js | ||
| pyproject.toml | ||
| README.md | ||
| SECURITY.md | ||
| stylelint.config.js | ||
| tsconfig.json | ||
| Vagrantfile | ||
| version.py | ||
Zulip overview
Zulip is an open-source team collaboration tool with unique topic-based threading that combines the best of email and chat to make remote work productive and delightful. Fortune 500 companies, leading open source projects, and thousands of other organizations use Zulip every day. Zulip is the only modern team chat app that is designed for both live and asynchronous conversations.
Zulip is built by a distributed community of developers from all around the world, with 74+ people who have each contributed 100+ commits. With over 1000 contributors merging over 500 commits a month, Zulip is the largest and fastest growing open source team chat project.
Come find us on the development community chat!
Getting started
-
Contributing code. Check out our guide for new contributors to get started. We have invested in making Zulip’s code highly readable, thoughtfully tested, and easy to modify. Beyond that, we have written an extraordinary 150K words of documentation for Zulip contributors.
-
Contributing non-code. Report an issue, translate Zulip into your language, or give us feedback. We'd love to hear from you, whether you've been using Zulip for years, or are just trying it out for the first time.
-
Checking Zulip out. The best way to see Zulip in action is to drop by the Zulip community server. We also recommend reading about Zulip's unique approach to organizing conversations.
-
Running a Zulip server. Self-host Zulip directly on Ubuntu or Debian Linux, in Docker, or with prebuilt images for Digital Ocean and Render. Learn more about self-hosting Zulip.
-
Using Zulip without setting up a server. Learn about Zulip Cloud hosting options. Zulip sponsors free Zulip Cloud Standard for hundreds of worthy organizations, including fellow open-source projects.
-
Participating in outreach programs like Google Summer of Code and Outreachy.
-
Supporting Zulip. Advocate for your organization to use Zulip, become a sponsor, write a review in the mobile app stores, or help others find Zulip.
You may also be interested in reading our blog, and following us on Twitter and LinkedIn.
Zulip is distributed under the Apache 2.0 license.