When we don't have an OutputService, precompute and cache the assumed-to-be-immutable filesystem type of output_base.

When we do have an OutputService, defer computation of the OutputService's dynamic filesystem type until we actually need it at the start of a "build" or "test" command.

This saves ~450us on each invocation, according to my benchmarks.

--
MOS_MIGRATED_REVID=121156323

1 files changed, 14 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/runtime/BlazeWorkspace.java b/src/main/java/com/google/devtools/build/lib/runtime/BlazeWorkspace.java
index aa98d3b98a..6652bd74ab 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/BlazeWorkspace.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/BlazeWorkspace.java
@@ -69,6 +69,8 @@ public final class BlazeWorkspace {
   @Nullable
   private Range<Long> lastExecutionRange = null;
 
+  private final String outputBaseFilesystemTypeName;
+
   public BlazeWorkspace(BlazeRuntime runtime, BlazeDirectories directories,
       SkyframeExecutor skyframeExecutor, SubscriberExceptionHandler eventBusExceptionHandler,
       WorkspaceStatusAction.Factory workspaceStatusActionFactory, BinTools binTools) {
@@ -85,6 +87,9 @@ public final class BlazeWorkspace {
       writeDoNotBuildHereFile(runtime.getStartupOptionsProvider());
     }
     setupExecRoot();
+    // Here we use outputBase instead of outputPath because we need a file system to create the
+    // latter.
+    this.outputBaseFilesystemTypeName = FileSystemUtils.getFileSystem(getOutputBase());
   }
 
   /**
@@ -126,6 +131,15 @@ public final class BlazeWorkspace {
   }
 
   /**
+   * Returns the cached value of
+   * {@code getOutputBase().getFilesystem().getFileSystemType(getOutputBase())}, which is assumed
+   * to be constant for a fixed workspace for the life of the Blaze server.
+   */
+  public String getOutputBaseFilesystemTypeName() {
+    return outputBaseFilesystemTypeName;
+  }
+
+  /**
    * Returns the output path associated with this Blaze server process..
    */
   public Path getOutputPath() {