Performance improvement

[damienlevin]

Switch from List to Vector to improve performance of append (http://docs.scala-lang.org/overviews/collections/performance-characteristics.html)

List

Done inserting list of 25000 in 1095 ms
Done requesting list of 25000 in 6029 ms
Done inserting list of 25000 in 464 ms
Done requesting list of 25000 in 6218 ms
Done inserting list of 25000 in 472 ms
Done requesting list of 25000 in 6209 ms
Done inserting list of 25000 in 457 ms
Done requesting list of 25000 in 6250 ms
Done inserting list of 25000 in 465 ms
Done requesting list of 25000 in 6219 ms
Done inserting list of 25000 in 479 ms
Done requesting list of 25000 in 6180 ms
Done inserting list of 25000 in 471 ms
Done requesting list of 25000 in 5517 ms
Done inserting list of 25000 in 458 ms
Done requesting list of 25000 in 5931 ms

Vector

Done inserting list of 25000 in 1164 ms
Done requesting list of 25000 in 253 ms
Done inserting list of 25000 in 530 ms
Done requesting list of 25000 in 132 ms
Done inserting list of 25000 in 468 ms
Done requesting list of 25000 in 98 ms
Done inserting list of 25000 in 483 ms
Done requesting list of 25000 in 95 ms
Done inserting list of 25000 in 494 ms
Done requesting list of 25000 in 100 ms
Done inserting list of 25000 in 453 ms
Done requesting list of 25000 in 105 ms
Done inserting list of 25000 in 461 ms
Done requesting list of 25000 in 102 ms
Done inserting list of 25000 in 471 ms
Done requesting list of 25000 in 98 ms

Test used:

package brando

import akka.util._

import akka.actor._
import akka.pattern._
import scala.concurrent._
import scala.concurrent.duration._

object TestApp extends App with ReplyParser {

implicit val t = Timeout(300.seconds)

import scala.concurrent.ExecutionContext.Implicits.global
val system = ActorSystem("system")
val redis = system.actorOf(Brando("localhost", 6379))

def testRequest(list: Int*) {
list.foldLeft(Future()) {
case (res, size) ⇒
for {
r ← res
m ← {
var start = 0L
for {
i ← {
start = System.currentTimeMillis
Future.traverse(1 to size) { i ⇒
redis ? Request("SADD", s"test-set-list-$size", s"el-$i")
}
}
m ← {
println(s"Done inserting list of $size in ${System.currentTimeMillis - start} ms")
start = System.currentTimeMillis
redis ? Request("SMEMBERS", s"test-set-list-$size")
}
p ← {
println(s"Done requesting list of $size in ${System.currentTimeMillis - start} ms")
redis ? Request("DEL", s"test-set-list-$size")
}
} yield (p)

      }
    } yield (m)
}

}

println("Global: Starting perf test...")
try {
// testRequest(1000, 5000, 10000, 15000, 20000, 25000, 30000, 35000)
testRequest(25000, 25000, 25000, 25000, 25000, 25000, 25000, 25000)

} catch {
case e: Exception ⇒ e.printStackTrace
}
}

[damienlevin]

This PR resolves #47

[chrisdinn]

fix seems to imply the primary performance issue was appending to the end of a list
interesting that could have such an impact!

[chrisdinn]

I think we can still beat 453ms to parse that list, but this is an awesome performance improvement. Thanks Damien!