sbt project is very slow to resolve dependencies - scala

Question

My sbt project takes more than 15 minutes when I do
sbt clean compile
I am on a beefy machine on AWS. I am fairly certain its not a resource issue on cpu or internet bandwidth. Also, I have run this command a few times and hence the ivy cache is populated.
Here is all my build related files
/build.sbt
name := "ProjectX"
version := "1.0"
scalaVersion := "2.10.5"
libraryDependencies += ("org.apache.spark" %% "spark-streaming" % "1.4.1")
.exclude("org.slf4j", "slf4j-log4j12")
.exclude("log4j", "log4j")
.exclude("commons-logging", "commons-logging")
.%("provided")
libraryDependencies += ("org.apache.spark" %% "spark-streaming-kinesis-asl" % "1.4.1")
.exclude("org.slf4j", "slf4j-log4j12")
.exclude("log4j", "log4j")
.exclude("commons-logging", "commons-logging")
libraryDependencies += "org.mongodb" %% "casbah" % "2.8.1"
//test
libraryDependencies += "org.scalatest" %% "scalatest" % "2.2.4" % "test"
//logging
libraryDependencies ++= Seq(
//facade
"org.slf4j" % "slf4j-api" % "1.7.12",
"org.clapper" %% "grizzled-slf4j" % "1.0.2",
//jcl (used by aws sdks)
"org.slf4j" % "jcl-over-slf4j" % "1.7.12",
//log4j1 (spark)
"org.slf4j" % "log4j-over-slf4j" % "1.7.12",
//log4j2
"org.apache.logging.log4j" % "log4j-api" % "2.3",
"org.apache.logging.log4j" % "log4j-core" % "2.3",
"org.apache.logging.log4j" % "log4j-slf4j-impl" % "2.3"
//alternative to log4j2
//"org.slf4j" % "slf4j-simple" % "1.7.5"
)
/project/build.properties
sbt.version = 0.13.8
/project/plugins.sbt
logLevel := Level.Warn
addSbtPlugin("org.scalastyle" %% "scalastyle-sbt-plugin" % "0.7.0")
resolvers += "sonatype-releases" at "https://oss.sonatype.org/content/repositories/releases/"
/project/assembly.sbt
addSbtPlugin("com.eed3si9n" % "sbt-assembly" % "0.13.0")

Answer 1

On the log do you see entries like:
[info] [SUCCESSFUL ] org.apache.spark#spark-streaming-kinesis-asl_2.10;1.4.1!spark-streaming-kinesis-asl_2.10.jar (239ms)
That's a sign that you're downloading these artifacts. In other words, the AMI you're launching doesn't have the Ivy cache populated.
Using sbt 0.13.12 on my laptop with SSD, I get about 5s for clean and then update.
so-31956971> update
[info] Updating {file:/xxx/so-31956971/}app...
[info] Resolving org.fusesource.jansi#jansi;1.4 ...
[info] Done updating.
[success] Total time: 5 s, completed Aug 25, 2016 4:00:00 AM