feat: add redis Unix Domain Socket support for high performance (#26)

* feat: add redis Unix Domain Socket support for high performance
* feat: add redis unix domain socket support for api.js
* wording enhancements

README.md

@@ -67,3 +67,94 @@ and if desired for UI testing:
 ```bash
 $ ./multinode-demo/client.sh --tx_count 40 --threads 2 -z 400
 ```
+
+## High Performance Use Cases
+
+### Redis via Unix Domain Socket
+
+Redis is known as a very fast in-memory data structure server. To keep up with Solana
+speeds, it may be useful to enable Unix Domain Socket communication for added performance
+(potentially 10-40% or more depending on the operations).
+
+Add configuration similar to the following to your `/etc/redis/redis.conf` (or equivalent):
+```
+unixsocket /var/run/redis/redis-server.sock
+unixsocketperm 770
+```
+
+Increasing max socket connections on Linux may also prove useful:
+```bash
+sudo sysctl net.core.somaxconn=16384
+```
+
+Remember to restart `redis-server` to pick up the new configuration:
+```bash
+sudo service redis-server restart
+```
+
+Ensure that your API unix user is in the same group as your `redis` user so it can read
+the file. For example, you may need to do something like this:
+```bash
+sudo chgrp -R ubuntu /var/run/redis
+```
+
+Finally, update the redis section of `api/config.js` to enable the `path` configuration
+which takes precedence over the host/port options:
+```js
+  ...
+  redis: {
+    ...
+    path: '/var/run/redis/redis-server.sock',
+  },
+  ...
+```
+
+If you would like to test Redis performance, the `redis-benchmark` tool is very handy
+for quick sanity checks while tuning configuration.
+
+Results using localhost TCP socket:
+```bash
+$ redis-benchmark -q -n 2000000 -c 1000 -P 40
+PING_INLINE: 567215.00 requests per second
+PING_BULK: 1021450.50 requests per second
+SET: 587026.69 requests per second
+GET: 741839.75 requests per second
+INCR: 619195.06 requests per second
+LPUSH: 671366.19 requests per second
+RPUSH: 810701.25 requests per second
+LPOP: 473372.78 requests per second
+RPOP: 769230.81 requests per second
+SADD: 925925.88 requests per second
+HSET: 693721.81 requests per second
+SPOP: 914494.75 requests per second
+LPUSH (needed to benchmark LRANGE): 547495.19 requests per second
+LRANGE_100 (first 100 elements): 34660.24 requests per second
+LRANGE_300 (first 300 elements): 9543.71 requests per second
+LRANGE_500 (first 450 elements): 6180.72 requests per second
+LRANGE_600 (first 600 elements): 4716.88 requests per second
+MSET (10 keys): 123137.54 requests per second
+```
+
+Results using Unix Domain Socket:
+```bash
+$ redis-benchmark -q -n 2000000 -c 1000 -P 40 -s /var/run/redis/redis-server.sock
+PING_INLINE: 1038421.62 requests per second
+PING_BULK: 1673640.12 requests per second
+SET: 896459.00 requests per second
+GET: 1175779.00 requests per second
+INCR: 1107419.75 requests per second
+LPUSH: 814995.94 requests per second
+RPUSH: 768049.12 requests per second
+LPOP: 775494.38 requests per second
+RPOP: 884564.38 requests per second
+SADD: 1047120.44 requests per second
+HSET: 758437.62 requests per second
+SPOP: 1275510.25 requests per second
+LPUSH (needed to benchmark LRANGE): 810372.81 requests per second
+LRANGE_100 (first 100 elements): 58491.50 requests per second
+LRANGE_300 (first 300 elements): 12462.15 requests per second
+LRANGE_500 (first 450 elements): 7449.32 requests per second
+LRANGE_600 (first 600 elements): 4019.78 requests per second
+MSET (10 keys): 120279.05 requests per second
+```
+

api/api.js

@@ -20,7 +20,11 @@ const port = 3001;
 const MINUTE_MS = 60 * 1000;
 
 function getClient() {
-  return redis.createClient(config.redis);
+  let props = config.redis.path
+    ? {path: config.redis.path}
+    : {host: config.redis.host, port: config.redis.port};
+
+  return redis.createClient(props);
 }
 
 expressWs(app);

api/config.js

@@ -10,5 +10,6 @@ export default {
   redis: {
     host: '127.0.0.1',
     port: 6379,
+    // path: '/var/run/redis/redis-server.sock',
   },
 };

api/inbound-stream.js

@@ -78,10 +78,11 @@ class BridgeFn {
 
 class RedisHandler {
   constructor(props) {
-    this.innerClient = redis.createClient({
-      host: props.host,
-      port: props.port,
-    });
+    const config = props.path
+      ? {path: props.path}
+      : {host: props.host, port: props.port};
+
+    this.innerClient = redis.createClient(config);
 
     this.process = this.process.bind(this);
   }