Merge branch 'master' into chore/package-lock

test/screenshot/infra/lib/cli.js

@@ -272,10 +272,9 @@ If a local dev server is not already running, one will be started for the durati
       type: 'integer',
       description: `
 Maximum number of browser VMs to run in parallel (subject to our CBT plan limit and VM availability).
-If no value is specified, the default is to start 2 browsers if nobody else is running tests, or 1 browser if other
-tests are already running.
-IMPORTANT: To ensure that multiple developers can run their tests simultaneously, DO NOT set this value during normal
-business hours.
+If no value is specified, the default behavior is to start half the number of available browsers.
+IMPORTANT: To ensure that other developers can run their tests too, DO NOT override this value during
+normal business hours.
 `,
     });
 

test/screenshot/infra/lib/selenium-api.js

@@ -395,17 +395,12 @@ class SeleniumApi {
       }
 
       if (this.isBusinessHours_()) {
-        // Nobody else is running tests.
-        if (active === 0) {
-          // Run half the number of concurrent tests allowed by our CBT account.
-          // This gives us _some_ parallelism while ensuring that other users can run their tests too.
-          return Math.floor(max / 2);
-        }
-
-        // Somebody else is running tests, so only run one test at a time.
-        return 1;
+        // Run half the number of concurrent tests allowed by our CBT account.
+        // This gives us _some_ parallelism while ensuring that other users can run their tests too.
+        return Math.floor(available / 2) || 1;
       }
 
+      // Outside of normal business hours, we can be greedy and take up all available parallels.
       return available;
     }
   }