Turn ClimaComms in a hard dependency

This should improve robustness of `OutputPathGenerator` in MPI settings.

NEWS.md

@@ -4,6 +4,11 @@ ClimaUtilities.jl Release Notes
 main
 ------
 
+#### `ClimaComms` is now a required dependency. PR [#127](https://github.com/CliMA/ClimaUtilities.jl/pull/127)
+
+`ClimaComms` used to be an optional dependency and was turned into a required
+one. The reason for this change is to improve robustness in MPI settings.
+
 v0.1.18
 ------
 

Project.toml

@@ -5,12 +5,12 @@ version = "0.1.18"
 
 [deps]
 Artifacts = "56f22d72-fd6d-98f1-02f0-08ddc0907c33"
+ClimaComms = "3a4d1b5c-c61d-41fd-a00a-5873ba7a1b0d"
 Dates = "ade2ca70-3891-5945-98fb-dc099432e06a"
 
 [weakdeps]
 Adapt = "79e6a3ab-5dfb-504d-930d-738a2a938a0e"
 CUDA = "052768ef-5323-5732-b1bb-66c8b64840ba"
-ClimaComms = "3a4d1b5c-c61d-41fd-a00a-5873ba7a1b0d"
 ClimaCore = "d414da3d-4745-48bb-8d80-42e94e092884"
 ClimaCoreTempestRemap = "d934ef94-cdd4-4710-83d6-720549644b70"
 Interpolations = "a98d9a8b-a2ab-59e6-89dd-64a1c18fca59"
@@ -21,8 +21,7 @@ ClimaUtilitiesClimaCoreExt = "ClimaCore"
 ClimaUtilitiesClimaCoreInterpolationsExt = ["ClimaCore", "Interpolations"]
 ClimaUtilitiesClimaCoreNCDatasetsExt = ["ClimaCore", "NCDatasets"]
 ClimaUtilitiesNCDatasetsExt = "NCDatasets"
-ClimaUtilitiesClimaCommsCUDAExt = ["ClimaComms", "CUDA"]
-ClimaUtilitiesClimaCommsExt = "ClimaComms"
+ClimaUtilitiesCUDAExt = "CUDA"
 ClimaUtilitiesClimaCoreTempestRemapExt = "ClimaCoreTempestRemap"
 
 [compat]

README.md

@@ -13,8 +13,8 @@ ClimaUtilities.jl
 
 `ClimaUtilities.jl` contains:
 - [`ClimaArtifacts`](https://clima.github.io/ClimaUtilities.jl/dev/climaartifacts/),
-  a module that provides an MPI-safe way to lazily download artifacts and to tag
-  artifacts that are being accessed in a given simulation.
+  a module that provides an MPI-safe (with `ClimaComms`) way to lazily download
+  artifacts and to tag artifacts that are being accessed in a given simulation.
 - [`SpaceVaryingInputs` and
   `TimeVaryingInputs`](https://clima.github.io/ClimaUtilities.jl/dev/inputs/) to
   work with external input data.
@@ -40,9 +40,9 @@ some differences.
 
 `ClimaUtilities.jl` is meant to be a foundational package, so it should have
 near-zero-cost for features that are not explicitly requested. This means that
-it should not depend on any package outside of the standard library and should
-have negligible import costs. To accomplish this, everything is implemented in
-Julia extensions.
+it should not depend on any package outside of the standard library and
+`ClimaComms` and should have negligible import costs. To accomplish this,
+everything is implemented in Julia extensions.
 
 Extensions are organized in the following way. The extensions defined in the
 `Project.toml` are defined in terms of the packages they require to be loaded.

docs/make.jl

@@ -62,7 +62,11 @@ makedocs(
             :ClimaUtilitiesClimaCoreNCDatasetsExt,
         ),
         Base.get_extension(ClimaUtilities, :ClimaUtilitiesNCDatasetsExt),
-        Base.get_extension(ClimaUtilities, :ClimaUtilitiesClimaCommsExt),
+        Base.get_extension(ClimaUtilities, :ClimaUtilitiesCUDAExt),
+        Base.get_extension(
+            ClimaUtilities,
+            :ClimaUtilitiesClimaCoreTempestRemapExt,
+        ),
     ],
 )
 

ext/ClimaUtilitiesClimaCommsCUDAExt.jl → ext/ClimaUtilitiesCUDAExt.jl

@@ -1,4 +1,4 @@
-module ClimaUtilitiesClimaCommsCUDAExt
+module ClimaUtilitiesCUDAExt
 
 import ClimaComms
 import ClimaUtilities

src/ClimaArtifacts.jl

@@ -3,7 +3,7 @@ module ClimaArtifacts
 import Base.BinaryPlatforms: HostPlatform
 import Artifacts as JuliaArtifacts
 
-import ..MPIUtils: root_or_singleton, maybe_wait
+import ClimaComms: iamroot, barrier
 
 export @clima_artifact
 
@@ -122,7 +122,8 @@ macro clima_artifact(name, context = nothing)
             # We call JuliaArtifacts._artifact_str twice, the first time only with the root
             # process (to avoid race conditions), the second time to ensure that all the
             # processes have the artifact string
-            if Base.invokelatest(root_or_singleton, $(esc(context)))
+            if isnothing($(esc(context))) ||
+               Base.invokelatest(iamroot, $(esc(context)))
                 artifact_path = Base.invokelatest(
                     JuliaArtifacts._artifact_str,
                     $(__module__),
@@ -181,7 +182,8 @@ macro clima_artifact(name, context = nothing)
             # We call JuliaArtifacts._artifact_str twice, the first time only with the root
             # process (to avoid race conditions), the second time to ensure that all the
             # processes have the artifact string
-            if Base.invokelatest(root_or_singleton, $(esc(context)))
+            if isnothing($(esc(context))) ||
+               Base.invokelatest(iamroot, $(esc(context)))
                 artifact_path = Base.invokelatest(
                     JuliaArtifacts._artifact_str,
                     $(__module__),
@@ -195,7 +197,8 @@ macro clima_artifact(name, context = nothing)
                 )::String
             end
             push!(ACCESSED_ARTIFACTS, artifact_name)
-            Base.invokelatest(maybe_wait, $(esc(context)))
+            isnothing($(esc(context))) ||
+                Base.invokelatest(barrier, $(esc(context)))
             Base.invokelatest(
                 JuliaArtifacts._artifact_str,
                 $(__module__),

src/ClimaUtilities.jl

@@ -1,7 +1,6 @@
 module ClimaUtilities
 
 include("Utils.jl")
-include("MPIUtils.jl")
 include("TimeManager.jl")
 include("DataStructures.jl")
 include("FileReaders.jl")

src/OutputPathGenerator.jl

@@ -5,10 +5,10 @@ et cetera.
 """
 module OutputPathGenerator
 
+import ClimaComms
+import ClimaComms: barrier, iamroot
 import ..Utils: sort_by_creation_time
 
-import ..MPIUtils: root_or_singleton, maybe_wait
-
 import Base: rm
 
 # Note, Styles have nothing to do with traits
@@ -39,7 +39,7 @@ function maybe_wait_filesystem(
     sleep_time = 0.1,
     max_attempts = 10,
 )
-    maybe_wait(context)
+    barrier(context)
     attempt = 1
     while attempt < max_attempts
         check_func(path) && return nothing
@@ -133,7 +133,7 @@ How the output should be structured (in terms of directory tree) is determined b
 """
 function generate_output_path(
     output_path;
-    context = nothing,
+    context = ClimaComms.context(),
     style::OutputPathGeneratorStyle = ActiveLinkStyle(),
 )
     output_path == "" && error("output_path cannot be empty")
@@ -148,9 +148,9 @@ Documentation for this function is in the `RemovePreexistingStyle` struct.
 function generate_output_path(
     ::RemovePreexistingStyle,
     output_path;
-    context = nothing,
+    context = ClimaComms.context(),
 )
-    if root_or_singleton(context)
+    if iamroot(context)
         if isdir(output_path)
             @warn "Removing $output_path"
             rm(output_path, recursive = true)
@@ -175,7 +175,7 @@ function generate_output_path(::ActiveLinkStyle, output_path; context = nothing)
     output_path = rstrip(output_path, path_separator_char) * path_separator_char
 
     # Create folder if it does not exist
-    if root_or_singleton(context)
+    if iamroot(context)
         isdir(output_path) || mkpath(output_path)
     end
     # For MPI runs, we have to make sure we are synced
@@ -197,7 +197,7 @@ function generate_output_path(::ActiveLinkStyle, output_path; context = nothing)
             next_counter = counter + 1
 
             # Remove old link
-            root_or_singleton(context) && rm(active_link)
+            iamroot(context) && rm(active_link)
         else
             error(
                 "Link $target points to a folder with a name we do not handle",
@@ -231,7 +231,7 @@ function generate_output_path(::ActiveLinkStyle, output_path; context = nothing)
     new_output_folder = joinpath(output_path, "output_$next_counter_str")
 
     # Make new folder
-    if root_or_singleton(context)
+    if iamroot(context)
         mkpath(new_output_folder)
         # On Windows, creating symlinks might require admin privileges. This depends on the
         # version of Windows and some of its settings (e.g., if "Developer Mode" is enabled).
@@ -256,7 +256,6 @@ function generate_output_path(::ActiveLinkStyle, output_path; context = nothing)
 end
 
 
-
 """
     detect_restart_file(base_output_dir;
                         restart_file_rx = r"day\\d+\\.\\w+\\.hdf5",