97 mbps !!! super fast

dosen't flush every message, pulls batches from the queue to send, and flushes at the end of each batch.
batches are a min of 1 message, but may be more.

src/server/client.zig

@@ -25,7 +25,7 @@ pub fn init(
 
 pub fn start(self: *Client, io: std.Io, alloc: std.mem.Allocator, queue: *std.Io.Queue(Message)) !void {
     self.recv_queue = queue;
-    var msgs: [16]Message = undefined;
+    var msgs: [8]Message = undefined;
     while (true) {
         const len = try queue.get(io, &msgs, 1);
         std.debug.assert(len <= msgs.len);
@@ -49,6 +49,7 @@ pub fn start(self: *Client, io: std.Io, alloc: std.mem.Allocator, queue: *std.Io
                 },
             }
         }
+        try self.to_client.flush();
     }
 }
 
@@ -68,19 +69,20 @@ pub fn next(self: *Client, allocator: std.mem.Allocator) !Message {
 
 fn writeOk(out: *std.Io.Writer) !void {
     _ = try out.write("+OK\r\n");
-    try out.flush();
+}
+
+fn writeErr(out: *std.Io.Writer, msg: []const u8) !void {
+    _ = try out.print("-ERR '{s}'\r\n", .{msg});
 }
 
 fn writePong(out: *std.Io.Writer) !void {
     _ = try out.write("PONG\r\n");
-    try out.flush();
 }
 
 pub fn writeInfo(out: *std.Io.Writer, info: Message.ServerInfo) !void {
     _ = try out.write("INFO ");
     try std.json.Stringify.value(info, .{}, out);
     _ = try out.write("\r\n");
-    try out.flush();
 }
 
 fn writeMsg(out: *std.Io.Writer, msg: Message.Msg) !void {
@@ -94,7 +96,6 @@ fn writeMsg(out: *std.Io.Writer, msg: Message.Msg) !void {
             msg.payload,
         },
     );
-    try out.flush();
 }
 
 test {