Fix #2 and add Rproj

drake-examples.Rproj

@@ -0,0 +1,15 @@
+Version: 1.0
+
+RestoreWorkspace: Default
+SaveWorkspace: Default
+AlwaysSaveHistory: Default
+
+EnableCodeIndexing: Yes
+UseSpacesForTab: Yes
+NumSpacesForTab: 2
+Encoding: UTF-8
+
+RnwWeave: Sweave
+LaTeX: pdfLaTeX
+
+BuildType: Makefile

overhead/README.md

@@ -1 +1,3 @@
-This example is explicitly designed to support profiling studies to make `drake` faster and more efficient. The workflow has `2n` targets, each with `n` dependencies. Increasing `n` up to 1000 puts heavy strain on the internals and dramatically increases runtime and cache size. Going forward, we want to make `drake` fast for this sort of task.
+This workflow is designed to maximize overhead and stress-test drake. The goal is to improve drake's internals so this example runs fast.
+
+Let n be the number of targets. There are n * (n - 1) / 2 non-file dependency connections among all the targets, which is the maximum possible. For i = 2, ..., n, target i depends on targets 1 through i - 1.

overhead/make.R

@@ -1,12 +1,20 @@
-# There are 2n targets, each with n dependencies.
-# You can increase n to put heavy strain on drake's internals for profiling.
+# This workflow is designed to maximize overhead and stress-test drake.
+# The goal is to improve drake's internals so this example runs fast.
+#
+# Let n be the number of targets.
+# There are n * (n - 1) / 2 non-file dependency connections
+# among all the targets, which is the maximum possible.
+# For i = 2, ..., n, target i depends on targets 1 through i - 1.
+
 n <- 4
 
 library(drake)
 library(magrittr)
-x <- drake_plan(x = sqrt(y__)) %>%
-  evaluate_plan(rules = list(y__ = seq_len(n)))
-y <- gather_plan(x, target = "y") %>%
-  expand_plan(values = seq_len(n))
-plan <- rbind(x, y)
+plan <- drake_plan(target_1 = 1)
+for (i in seq_len(n - 1) + 1){
+  target <- paste0("target_", i)
+  dependencies <- paste0("target_", seq_len(i - 1))
+  command <- paste0("max(", paste0(dependencies, collapse = ", "), ")")
+  plan <- rbind(plan, data.frame(target = target, command = command))
+}
 make(plan)