first public version

.gitignore

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+erl_crash.dump
+.envrc
+.elixir-tools
+erl_crash.dump

LICENSE

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+
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Makefile

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+
+.PHONY: default
+default: deploy logs
+
+.PHONY: deploy
+deploy:
+	docker compose up -d
+
+.PHONY: logs
+logs: deploy
+	docker compose logs clients -f
+
+.PHONY: load-generator
+load-generator:
+	cd ./load_generator && make docker
+
+tps ?= 1
+duration ?= 300
+size ?= 16
+
+.PHONY: txns
+txns: load-generator
+	docker run \
+		--rm \
+		-t \
+		--network 1e6_default \
+		electricsql/load-generator:latest \
+		--db "postgresql://postgres:password@postgres:5432/electric" \
+		-c "value:text:$(size)" \
+		--tps "$(tps)" \
+		--duration "$(duration)"
+
+.PHONY: stop
+stop:
+	docker compose down --volumes

README.md

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+# Electric Load Generation
+
+Code to load test an Electric instance by simulating any number of concurrently connected clients.
+
+## Running Locally
+
+This repo has a docker compose setup that allows for running a full end-to-end
+test of the electric stack on your local machine.
+
+1.  `make clients=1000` - builds and launches a self-contained electric
+    instance, fronted by a Varnish proxy with 1000 clients connected over HTTP
+
+    Options:
+
+    - `clients=N` set the number of clients to launch and connect. Default `1000`.
+
+          make clients=2000
+
+2.  `make txns duration=60 tps=8` - generates 8 database transactions per second for 60 seconds
+
+    Options:
+
+    - `duration=S` run for `S` seconds, default `300`
+
+          make txns duration=60
+
+    - `tps=N` insert `N` rows per second, default `1`
+
+          make txns tps=4
+
+As the clients receive the db transactions, you will see messages from the client coordinator.
+
+- `[start: [id: ID, ...` - the row with id `ID` has been received by a client
+
+- `[complete: [id: ID, ...` - the row with id `ID` has been received by all
+  clients. The `duration` value here is the time in milliseconds between the
+  receipt of the first `start` message and the last.
+
+### Statistics
+
+If you connect to the stack's pg database:
+
+    psql "postgresql://postgres:[email protected]:5555/electric"
+
+You can see some views that show the latency statistics, i.e. the time between the transaction write and receipt by the electric clients:
+
+To see overall statistics for latencies for all sampled transactions:
+
+     select * from latency_overview;
+
+And for the latencies of the first receipt:
+
+     select * from latency_overview1;
+
+All latencies are in milliseconds.
+
+See [postgres/init.sql](./postgres/init.sql) for the full set of views and db schema.
+
+## Deploying Using Fly
+
+You can also generate client connections to a real Electric instance (running
+behind a CDN) using Fly to bring up a geo-distributed set of client load
+instances.
+
+The `client_load` directory has a `fly.toml` file suitable for deploying any
+number of instances.
+
+Assuming that your (CDN fronted) electric instance is running at
+`https://cdn.electric.my-app.com` and is connected to some database at
+`postgresql://usr:[email protected]`:
+
+- Make sure your Postgres instance has the right schema as defined in
+  [postgres/init.sql](./postgres/init.sql)
+
+- Edit the [fly config](./client_load/fly.toml):
+
+  Set:
+
+  - `ELECTRIC_URL` to e.g. `https://cdn.electric.my-app.com`
+  - `DATABASE_URL` to e.g. `postgresql://user:[email protected]`
+  - `CLIENT_COUNT` this defaults to `5000` but, depending on your workload, as
+    in the number of transactions per second you're generating, can be pushed to
+    `10000` or `15000`.
+
+- Deploy it to your fly account:
+
+      cd client_load
+      fly deploy --ha=false
+
+  And scale it to the number of active connections you want:
+
+      cd client_load
+      fly scale count 10 --region ams,lhr,mad,fra,cdg,arn,otp
+
+  Fly recommends spreading your machines across various regions. The above
+  example uses Fly's European data centres. Every machine will create
+  `CLIENT_COUNT` connections.
+
+- Generate some database transactions:
+
+      DATABASE_URL="postgresql://usr:[email protected]" make txns
+
+- Monitor your clients:
+
+      cd client_load
+      fly logs
+
+  As for the local setup, latency statistics will be written to your Postgres instance.
+
+- Once you're done, scale down your client machines:
+
+      cd client_load
+      fly scale count 0

client_load/.dockerignore

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+# flyctl launch added from .gitignore
+# The directory Mix will write compiled artifacts to.
+_build
+
+# If you run "mix test --cover", coverage assets end up here.
+cover
+
+# The directory Mix downloads your dependencies sources to.
+deps
+
+# Where third-party dependencies like ExDoc output generated docs.
+doc
+
+# Ignore .fetch files in case you like to edit your project deps locally.
+.fetch
+
+# If the VM crashes, it generates a dump, let's ignore it too.
+**/erl_crash.dump
+
+# Also ignore archive artifacts (built via "mix archive.build").
+**/*.ez
+
+# Ignore package tarball (built via "mix hex.build").
+**/client_load-*.tar
+
+# Temporary files, for example, from tests.
+tmp
+fly.toml
+statistics
+statistics.*
+client_load/_build
+client_load/deps
+client_load/test
+.elixir-tools

client_load/.formatter.exs

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+# Used by "mix format"
+[
+  inputs: ["{mix,.formatter}.exs", "{config,lib,test}/**/*.{ex,exs}"]
+]